83 280ZX won't start, won't fire. Just turns over.

[jmw_man]

Hi all,

It's been a while since I posted.

Anyhow, my Z has started giving me problems after running pretty good for the last year. This problem started about a couple months ago. One day I got in it and tried to start and it just turned over and over and over and I never heard the sound of ignition as if there was no fuel or spark. Then moments later it fired right up.

As the days progressed since then, those moments between not firing to firing right up increased to the point now that it won't fire at all.

First off I want to point out that I've done some browsing around the internet for other people having this problem and I have found forum thread of such people. The PROBLEM is, those threads were largely unanswered or the OP never came back to update as to what was causing his Z's problem.

Spark, air, and fuel right? Well,...

Air - Nothing looks suspicious there.

Fuel - I hear the fuel pump. I haven't checked the pressure yet but the pump is definitely working. Fuel is also definitely making it past the filter too. I say this because I noticed a tiny fuel leak near the injectors. More specifically, the number 3 or 4 injector. The line that goes to it will get soaked which I find really odd. I need to look into that further but I think that might be a separate issue. Let me ask this. Is it possibly my injectors are clogged enough that this could happen? Also, maybe someone can shed some light on this question but does the injector ONLY squirt fuel when it receives a signal from the computer? This is something I need to look into. I have pulled the control unit or whatever it's called and checked all the pins and everything that's supposed to have battery voltage does have battery voltage including the 6 pins that go to the injectors. FYI, I have the E.F.I engine I believe because I have a cold start valve. If I remember correctly the E.C.C.S engine doesn't have the cold start valve. Anyways, I was going through the EFEC section of the FSM, particularly pages 83 and up to check the control unit. All of the injectors had voltage. As far as diagnosing a possible fuel problem, I just need to know if it's possible for 6 injectors to all clog in the same timeframe. I also need to learn how to test each individual injector. I can't imagine that all 6 injectors have stopped receiving voltage at the same time. Maybe someone knows what I'm talking about.

Spark - It's not the coil, I changed it out, still experience intermittent starting with new coil. I doubt all spark plugs went out at the same time. Is it possible that the timing could be soooooo faaaar off that it won't fire? I can't imagine that being possible. Everything looks normal under the distributor cap. Can someone point me in the direction of a list of steps to further my diagnosis?

Thanks,
jmw

[Zed Head]

Check for spark first. Make sure it's a good solid blue spark, not a weak thin yellowish spark. If you have no spark...

A bad ignition module or dirty connections at the ignition module are a possibility. They're in a dirty. dusty spot and the rubber seals and wire insulation tend to get baked and cracked. The module and coil need a good voltage supply to create a good spark. When the engine is cranking voltage drops. A few more lost volts due to dirty connections could be enough to weaken the spark during starting.

Finally, when did you last give it a tune-up? Worn, dirty spark-plugs can cause problems.

[jmw_man]

Check for spark first. Make sure it's a good solid blue spark, not a weak thin yellowish spark. If you have no spark...

A bad ignition module or dirty connections at the ignition module are a possibility. They're in a dirty. dusty spot and the rubber seals and wire insulation tend to get baked and cracked. The module and coil need a good voltage supply to create a good spark. When the engine is cranking voltage drops. A few more lost volts due to dirty connections could be enough to weaken the spark during starting.

Finally, when did you last give it a tune-up? Worn, dirty spark-plugs can cause problems.

What's the best method for checking for spark if you are alone and don't have a second pair of hands to rotate the engine?

I'll inspect the ignition module. Um, can you point me towards the section of the FSM that covers this? I'm browsing it right now and I can't seem to find any mention of the ignition module.

I put in new plugs maybe a year or so ago if I recall correctly, along with new wires, dizzy cap and rotor.

I also have the IC type distributor, anything in there I need to check?


Edit: I just saw a google image that shows the ignition module is attached to the distributor, I'll look there.

[EuroDat]

The IC's I have played with generally don't give problems when cold, but Zed Head said is a good point. They need good voltage to work. If the voltage drops off to much they will stop triggering. You should run through the checks in the FSM and make sure all the wiring for the ignition is ok.

I would also invest in a gauge to messure the fuel pressure. It could also be suffering leak down through the check valve in the pump of FPR and it taking time to build up pressure again. A gauge can tell you a lot here.

Goodluck
Chas

[jmw_man]

The IC's I have played with generally don't give problems when cold, but Zed Head said is a good point. They need good voltage to work. If the voltage drops off to much they will stop triggering. You should run through the checks in the FSM and make sure all the wiring for the ignition is ok.

I would also invest in a gauge to messure the fuel pressure. It could also be suffering leak down through the check valve in the pump of FPR and it taking time to build up pressure again. A gauge can tell you a lot here.

Goodluck
Chas

The sucky part is that I noticed many of those tests require a second pair of hand to crank the engine while you use a voltmeter. I wish there was another way. Anyways, I can at least inspect the wiring.

I have the fuel pressure gauge, just haven't gotten around to checking the pressure (or been spending too much time on the mustang). What does FPR stand for?

[Zed Head]

One of the handy features of the Z's and ZX's is that the hood opens forward. Get some 1 - 2' test leads with alligator clips on each end and set the meter up where you can see it from inside the car.

[jmw_man]

One of the handy features of the Z's and ZX's is that the hood opens forward. Get some 1 - 2' test leads with alligator clips on each end and set the meter up where you can see it from inside the car.

That's exactly what I did, lol.

Well, I did two tests. Although, I need guidance.

I went out there and first inspected the ignition module and the two connectors that are plugged into it. They looked dirty but I didn't clean them yet. The two tests I did are from pages EL-28 and EL-29 from the FSM steps number 5 and 7. First I want to point out that the FSM doesn't seem clear to me whether I'm supposed to connect the lead to the female or the male connector.

Step 5: When I hooked it to the connector that's on the ignition module side, the voltage read .7 volts. When I hooked it to the connector that's on the wire side, the voltage read 11.98 volts. Which side was I supposed to connect it to? I'm guessing the latter.

Step 7: When I hooked it to the connector that's on the ignition module side, the voltage read 0 volts. When I hooked it to the connector that's on the wire side, the voltage read 11.98 volts. Again, which side did they mean for me to connect it to?

In both of the above scenarios it was supposed to read between 11.5 and 12.5 volts so if in both scenarios I'm supposed to connect it to the wire side then both tests were good.

I also want to point out that a couple weeks ago I had already tested the coil secondary and primary resistances, step 4 and step 8. Step 4 was good as it was in the range of 8200 to 12400 ohms. However, step 8 had a reading of 2.1 ohms. 2 weeks ago I assumed my coil was faulty so I bought a new one. The new one had a primary resistance of 2 ohms as well and so did the second new one. So, I returned the two new coils and just kept the old one. That particular reading was supposed to be between .84 ohms and 1.02 ohms. I'm not sure why the primary resistance is so high on the new coils.

Anyways, after doing the step 5 and step 7 tests, I used my can of electronic cleaner and cleaned all connectors attached to the ignition module and retested. I came back with the same results. So far I feel like I haven't really narrowed down to anything. I then decided I'd give her a try and crank her up. Well she fired right up. So I don't know if that means my tests were null and void. That's why I hate intermittent problems like this.....

Next I plan to test the fuel pressure. Since I got it running I unplugged the wire that goes to the fuel pump and let it die to depressurize. I'll try to get back out there to hook up my fuel pressure gauge.

[Zed Head]

The test connections are at the connector/plug ("receptacle" = receiver) so your second tests were correct, and results look good. I would do Test #6, since that measures voltage during starting. Your starter could be drawing too many volts or your battery could be weak.

I would also do something similar Test #9, since the module grounds through the distributor body, except Iwould just measure resistance to ground. The ground is the other important part, that allows current flow. You can have correct voltage but low current and have problems. Measure resistance from the distributor body to the engine block. I don't know why they test voltage drop with the coil discharging. It seems like a good way to make a mistake and damage the module. Check the ground first.

[jmw_man]

The test connections are at the connector/plug ("receptacle" = receiver) so your second tests were correct, and results look good. I would do Test #6, since that measures voltage during starting. Your starter could be drawing too many volts or your battery could be weak.

I would also do something similar Test #9, since the module grounds through the distributor body, except Iwould just measure resistance to ground. The ground is the other important part, that allows current flow. You can have correct voltage but low current and have problems. Measure resistance from the distributor body to the engine block. I don't know why they test voltage drop with the coil discharging. It seems like a good way to make a mistake and damage the module. Check the ground first.

On test number 6 and 9, I didn't do because I wasn't sure if there was a specific way I should ground the coil wire. Isn't the coil wire some kind of positive voltage and grounding it would be bad for the battery or something? Do I just use my jumper wires and connect it to the coil wire and a ground somewhere and not worry?

[Zed Head]

Oops, I missed the fact that Test 6 asks the same thing.

What they want you to do is to ground the center wire of the coil, the big one that's the same size as a plug wire, to the block so that the current from the coil has somewhere to go. So that you can crank the engine over without the engine starting. So pop the wire out of the distributor cap. leave it connected to the coil, and place or clamp the metal end against a solid piece of metal on the engine block. Just make sure that it's solidly placed, if it gets loose it can spark to things that shouldn't get spark. And if it's too far away to spark, the electrical pulse can do other damage if it has no way to discharge. As I understand things. The spark from that wire will be a big one.

[jmw_man]

Fuel pressure readings:

Turn key to on, fuel pump turned on for 5 seconds, pressure went up to 32 psi. Started car, fuel pressure was steady around 28 psi.

[siteunseen]

How old is the fuel filter? They're $15 at chain parts stores and always better than the one you have now.

[jmw_man]

It's about a year old. It probably has less than 3000 miles on it. It's a daily driver but only to the corner store for milk, lol.

There's a few electrical tests I still need to do. Hopefully I get out there today.

[jmw_man]

The test connections are at the connector/plug ("receptacle" = receiver) so your second tests were correct, and results look good. I would do Test #6, since that measures voltage during starting. Your starter could be drawing too many volts or your battery could be weak.

I would also do something similar Test #9, since the module grounds through the distributor body, except Iwould just measure resistance to ground. The ground is the other important part, that allows current flow. You can have correct voltage but low current and have problems. Measure resistance from the distributor body to the engine block. I don't know why they test voltage drop with the coil discharging. It seems like a good way to make a mistake and damage the module. Check the ground first.

I did test number 6 and 9.

Test 6 was steady around 9.5 volts which is good because it needs to be greater than 8.6 volts.

Test 9 was steady around .2 volts which is good because it needs to be less than .5 volts, however, for a split second I saw it jump up to 1.2 volts and I though I hear the sound of a spark but it was only for a split second. That happened when I cranked it over the first time but it fell back to .2 volts and held steady. I then cranked it over a second time to try and see if it would do it again but it didn't, it just held steady around .2 the whole time second time around.

Now, before doing these two tests, I tried starting it and the car started fine. For all I know the car got fixed when I sprayed the electronic cleaner into the connectors around the dizzy. We shall see.

[jmw_man]

Nope, the problem is still there....

Went to O'Reilly's, started no problem, but when I left there it took a while to get it to start. Also, I noticed that when it finally does start it seems weak as if something barely ignited and that helped it start.

Let me ask this, a few weeks ago I adjusted the timing when I didn't know what I was doing. I adjusted it according to what the suggested initial timing should be as listed in the FSM, INSTEAD of adjusting for high rpm/high vacuum. The timing was probably 16 degrees at the time so I ended up retarding it, can't remember what I retarded it to. Anyways, here's the question, is it possible to retard the timing so much that the car will have trouble starting?

[Zed Head]

Timing could be a factor but it would most likely be a consistent problem. Does the no-start happen randomly, whether the engine is cold or hot, or is it only when hot?

[jmw_man]

Timing could be a factor but it would most likely be a consistent problem. Does the no-start happen randomly, whether the engine is cold or hot, or is it only when hot?

Random, temperature doesn't seem to be a factor.

[siteunseen]

is it possible to retard the timing so much that the car will have trouble starting?

Yes it is.

Barely loosen the distributor hold down plate, put a golf tee in the vacuum hose off the vacuum advance and crank it. Turn it which ever way makes the valve train noise quietists then turn it counter clockwise about a 1/4" or so, if I recall correctly.

[jmw_man]

Yes it is.

Barely loosen the distributor hold down plate, put a golf tee in the vacuum hose off the vacuum advance and crank it. Turn it which ever way makes the valve train noise quietists then turn it counter clockwise about a 1/4" or so, if I recall correctly.

Do I do that while it's running?

Edit: nm, wouldn't make sense to not do it while it's running.

[siteunseen]

That's the way I learned without a light. Get it real quiet then back it up a tad.
Good luck!

[jmw_man]

I don't even know what the sound of the valve train sounds like, lol.

[jmw_man]

, I look down and I see the titles of some other threads: "turns over won't start", "turns over won't start", "turns over won't start"....

I'm trying to get my 65 mustang to start too. It turns over and it fires when I spray a bit of starter fluid. I'm just not sure how those mechanical pumps work. Obviously you aren't pumping fuel with the gas pedal while the engine is off... Anyways, got an active thread on a mustang forum going too. Still work in progress...

[siteunseen]

On our carbureted motors with a mechanical fuel pump there's an off center cup looking thing on the cam's nose in front of the timing sprocket that moves the pump's arm every time the cam turns. Ehh here's something I found on google, How A Fuel Pump Works

[jmw_man]

On our carbureted motors with a mechanical fuel pump there's an off center cup looking thing on the cam's nose in front of the timing sprocket that moves the pump's arm every time the cam turns. Ehh here's something I found on google, How A Fuel Pump Works

I see, so while the engine is cranking the fuel pump should be sending fuel to the carburetor. Thanks for the link.

[siteunseen]

Obviously you aren't pumping fuel with the gas pedal while the engine is off

My MaMaw used to pump the gas pedal in her Cadillac about 10 times before turning the key. My Dad said she was nuts but that Batmobile always cranked right up.
Maybe that's where the term "double pumper" comes from?

[jmw_man]

Got the stang running. It took a good amount of carb cleaner.

Back to the Z....

I feel like I just need to wait till it won't ever start....

[Zed Head]

I would take a look at the relays involved. They're mechanical and do get stuck or sticky. Actually, I would just trace out the whole circuit that feeds the ignition system and the EFI system and examine each component and connection. I know someone that had a fuse in the trunk that would overheat while driving, opening the circuit at the connection points and killing everything, but leaving the fuse intact. After cooling, back to normal. It was a BMW though, so not directly applicable.

[jmw_man]

After cooling, back to normal.

Explain that part?

[Zed Head]

Things expand when they get warm. Gaps can open up. That's all. The current flowing through the wire and fuse caused the parts to heat up, the gap opened, the current stopped, the engine died. Then he would he sit beside the road and wait, the gap would close, the current could flow again, and he'd start the engine and drive on.

[jmw_man]

Oh, I got a remote starter so I could turn the engine while under the hood. Number 1 spark plug isn't sparking. I didn't check the others. The problem is definitely a spark problem. Still won't start. The problem no longer seems intermittent, it won't ever start now.

Anybody know of a way for me to test spark at the coil?

Edit: Although, as previously stated, I don't think it's the coil because way back when I put a new one in it still experienced the same problem. It's gotta be a bad ignition module. I'm thinking of just buying a new one. The tests I did on the ignition module a while back didn't fail it but the problem was afterall still intermittent. I'll just get a new one and then update here.

[Patcon]

As for the old cars and double pumper. Many four barrel carbs and some 2 barrels have an accelerator pump. double pumpers have 2 pumps, hence double pumpers. When the throttle is depressed the pump is operated by a cam and pumps fuel into the carb throat thru a jet. So in actuality you can pump fuel with the throttle on some cars. That is why she stepped on the throttle, to prime the car so it would start. Also on many older cars you have to depress the throttle all the way to the floor to set the choke. Doing it twice can knock the choke off. FWIW
Charles

[Zed Head]

Anybody know of a way for me to test spark at the coil?

.

You can connect a jumper wire to the negative post of the coil. Leave the other end hanging in air. Disconnect the center wire of the coil from the distributor cap and place it very close, about a spark plug gap distance, from a ground path, like the intake manifold or the car body. Turn the key to On/Run. Then tap the end of the wire to a ground path, like the engine block or intake manifold. Don't hold it there, just tap it quickly. Each tap should generate a spark at the center coil wire. Every third spark should cause the injectors to all click. If you get spark this way, that means the coil is working correctly, and if you get injector clicking, the ECU and its wiring.

[jmw_man]

Well crud. I thought for sure I'd be able to buy the ignition module at a cheap price because I saw that O'Reilly's lists the BWD part and another house brand for under $100. It turns out that they can't get those anymore and they could only offer something over $100. Actually, I think it was closer to $150 for their cheapest ignition module. Any pointers?

[Zed Head]

Looks like Rockauto has one for ~$85. But with the ZX distributors there are other things that tend to break, like the stator magnet, or the pickup coil, or the bushings in the distributor (which can break the magnet). You might be wasting your money assuming it's the module. Have you checked the distributor for damage? Might be better off to just get a complete distributor. Also on Rockauto for not much more.

In Post 30 you didn't mention if the key was on. With the remote starter you can turn the motor but not get spark if the key isn't on.

Do the test with the wire first, that will tell you if the the parts after the module are working. Tapping the wire, you will be doing essentially what the module does.

[EuroDat]

If the coil tests ok and it turns out to be the TIU in the dizzy there is a write up in http://www.classiczcars.com/forums/t...tml#post446171 on how to replace it with a HEI module.
A HEI module costs as little as $10 and will get it running. Gives you time to search for a good replacement distributor or make the HEI a perminent fix.
I had similar problems on my 77 280Z and did the HEI mod. The 280Z system is a little different with the TIU in the car, but the principle workings are the same.
Chas

[Zed Head]

I almost mentioned the GM HEI also. But I think that 1983 used the E12-92 module, as opposed to E12-80, which has a timing advance circuit, for emission purposes. Kind of like the dual point/pickup Z engines, controlled by a "thermo switch". It's doable, but he'd lose the advance circuit. Probably not a big deal but something to consider.

Might be worth the $20 and time though, to just wire in an HEI module to confirm that the stock module is bad, then decide whether or not to spend the $100+ to get the replacement. If it's not the module, he's only out the $20.

[jmw_man]

Looks like Rockauto has one for ~$85. But with the ZX distributors there are other things that tend to break, like the stator magnet, or the pickup coil, or the bushings in the distributor (which can break the magnet). You might be wasting your money assuming it's the module. Have you checked the distributor for damage? Might be better off to just get a complete distributor. Also on Rockauto for not much more.

In Post 30 you didn't mention if the key was on. With the remote starter you can turn the motor but not get spark if the key isn't on.

Do the test with the wire first, that will tell you if the the parts after the module are working. Tapping the wire, you will be doing essentially what the module does.

Good point about the distributor. RockAuto shows the Cardone at $141.79. The same exact part at O'Reilly Auto is $201.99. Definitely not a bad option since the module is the same price as the dizzy from RockAuto.

As for testing the spark plug for spark, no, I didn't have the key on. I'll have to retest. I tried to retest about an hour ago, but the engine started...... go figure. So I setup the timing light and the remote start and closed the hood. I'll just wait till later when it won't start and I'll already be setup. By the way, when it started, I turned it up, hooked up the timing light and the remote starter and did a test run with the remote starter and it started up the second time as well but it seemed like it hesitated, very slow startup like it barely caught. Anyhow, I'll just test for spark later when it won't start.

Step 2, I'll do the wire test on the coil as you described.

Step 3, I'll look into the GM HEI module option.

[rcb280z]

I would make sure the one from rockauto is complete, with module. Not saying it isn't but I would double check. Rockauto has been good to me.

[jmw_man]

OKAY,

I retested for spark in number one with timing light while the key was in the on position. Result: no spark.

I did the wire test on the coil as you described. Result: no spark at end of high tension coil wire, but there was a spark at end of the jumper wire. Also, you said that every third spark I should hear the injectors clicking. Well, the injectors made a "flowing" sound at "every" spark between the manifold and the jumper wire. It didn't matter what I did with the high tension coil wire I disconnected from the dizzy, it just wouldn't ever spark. Now, one observation I did make is that the coil got hot.

Here's the thing, a month and a half or so ago I bought a brand new coil and put it in. I still had the same intermittent starting problem I'm having today, so i feel like my problem must be "before" the coil. What do yall think?

[jmw_man]

OKAY,

I retested for spark in number one with timing light while the key was in the on position. Result: no spark.

I did the wire test on the coil as you described. Result: no spark at end of high tension coil wire, but there was a spark at end of the jumper wire. Also, you said that every third spark I should hear the injectors clicking. Well, the injectors made a "flowing" sound at "every" spark between the manifold and the jumper wire. It didn't matter what I did with the high tension coil wire I disconnected from the dizzy, it just wouldn't ever spark. Now, one observation I did make is that the coil got hot.

Here's the thing, a month and a half or so ago I bought a brand new coil and put it in. I still had the same intermittent starting problem I'm having today, so i feel like my problem must be "before" the coil. What do yall think?

[Zed Head]

The coil got hot just because the key was On? That would be short circuit somewhere after the negative post of the coil. The module could very well be shorted internally. That would heat up the coil and kill the spark, with the key On.

Try disconnecting the blue and brown wire from the module and see if the coil still gets hot. If the coil only gets hot when the key is on and the module is connected but not when the module is disconnected that's a sign the the module is shorted/bad. Make sure though, that the blue wire is not shorted to ground anywhere on the way between the module and coil. That would cause the same symptoms.

[Zed Head]

The site's acting weird and won't let me add to my last post so...I was going to add that the reason you don't get a spark is because the current through the coil is never shut off. That's also why the coil gets hot. Current flow is stuck on for some reason. Disconnecting the module will be informative. It does look a lot like a bad module.

[EuroDat]

I agree with zed head. Sounds a lot like bad module or a short to ground in the negative (blue) going to the coil. It looks like you are narrowing the problem down.
Good luck with it.
Chas

[EuroDat]

I agree with zed head. Sounds a lot like bad module or a short to ground in the negative (blue) going to the coil. It looks like you are narrowing the problem down.
Good luck with it.
Chas

[EuroDat]

Something freaky about the forum. Double post and can't edit the second one

[jmw_man]

Well, when I said the coil got hot, it got hot with key on AND I was sparking with the jumper wire from the negative on coil to the manifold. I don't know if it would get hot with "just the key on" and without me grounding the coil's negative post. I'll see what the coil feels like with just the key in on position tomorrow. I'll also disconnect the blue and brown wire from the module and check the temp tomorrow. By the way, is that the upper connector on module or the lower connector?

[jmw_man]

Chilly morning here in Dallas. I can't do any of my tests because the car keeps starting, lol. I tried starting it about 3 hours ago and it started, then I just went back out a couple minutes ago and it started again. The coil seems to remain cold while the key is on but I'm guessing this is normal if my car is starting normally right now. I'll update later if the car ever fails to start.

[EuroDat]

A failing TIU can often be temperature related. Mine would work great when cold and started failing after driving for a while. It did start doing it once in the garage before I wanted to leave. That was in the middle of summer.

I made a tester by using a hose clamp to fix a spark plug to a bracket and bolted it to the strut tower. That way I could use a hi tension lead to the spark plug and crank the engine from the drivers seat while checking for spark with out anyone helping. Yer it always seemed to play up when I was alone. You just need to be creative.
If you do make something like that, test it while its working fine. Thaf way yoh will know what it should look like.
Chas

[Zed Head]

Since the temperature for failure is so low, apparently, you might try the opposite of the typical ignition module over-heat test. Instead of cooling the module, heat it up. Start the car, let it run, and blow hot air on the module with a heat gun or hair dryer. If it is the module, the engine should start running poorly or die pretty quickly.

Looks like you're almost there. If it's not the module, and you're still getting spark when it dies, then that leaves the injection circuit. Maybe the ECU. Probably best to hope it's the module.

[siteunseen]

Chas you're like me. I'll ask total strangers for help on here but won't let anybody put hands on mine, they make me nervous.