S12 CA20E Firing problem (NEED HELP FAST!!!)

[oldsilvia-s12]

Ok, last summer, I had a firing issue with my S12. The fire was shutting down suddenly for no reason. I change THE WHOLE firing system (spark plug, spark plug wire, ignitor chip, ignition coil, distributor, cap distributor) And this week, I take it out for the 1st time of the years ( Long quebecers winter) And damnit it doesnt wanna start. The starter is turning, the fuel pump is pumping. But there is no fire. After 5-6 try, the car start, it fire fine. I let it idle and about 3 minutes later, the car was shutted donw suddenly, like if I had turn of the key... exactly like last summer.

So now i'm trying to see what is wrong, I just find an unpluged plug from the distributor, the plug that come from the vacuum on top of the distributor. I'm trying to find out where it plug but it seem that the other part of the plug is missing...

What else can it be?

[eds13]

moved here for better responce hopefully

[davidricardo86]

Heres a short list of things id go over just to make sure everything is ok.

1. Check computer for trouble codes2. Check all fuses and relay wiring3. Check engine grounds4. Check for ignition spark5. Inspect the distributor cap and rotor 6. Inspect the ingition coil7. Test and verify spark plug wire resistance8. Check spark plugs and gap9. Check base ignition timing10. Check fuel pressure11. Check fuel pump operation12. Check fuel injector(s) operation with DVOM (use a wiring diagram)13. Check vacuum14. Check for any vacuum leaks

These are a few simple tests you can perform on your own to try to pin-point the problem. Go through this list and post back your results. Download a Factory Service Manual if you havent done so already.

[johngriff]

I dont know why this would be moved here.

CA18DET is COP/CAS.

CA20E is Dist.

So, EGI relay is shutting ignition system down because of a bad wire between it and the coil.

[davidricardo86]

I dont know why this would be moved here.

CA18DET is COP/CAS.

CA20E is Dist.

So, EGI relay is shutting ignition system down because of a bad wire between it and the coil.

Well it is the "CA" forum but im sure we can still help this guy out....

[oldsilvia-s12]

Don't matter where the post is, as long I solve my problem.

I'm gonna check the list of thing to check. But I'm sure it's not a fuel issue. When I start having this problem, I bring the car to a competent shop and tell them to overhaul every parameter. Especially for the fuel pressure. Everything was all right.

And the way its cutting is very obious, it's not like if the car was hesitating or anything. When the engine stop sparking, it's really like if I was turning the key off. the EGI- coil wire might be the problem. I've completely dissambled the air box and play with the wires and plugs around the distributor and EGI. I put back everything on, and the car started fine... and I run around with it with no problem... But I must to find why it was dooing that, before the problem came back.

What i can already clear from the list:-distributor cap, rotor, spark plugs, spark plug wires and ignition coil (brand new, already change them to try to solve the problem)-fuel pump, injectors, (I hear it when I turn the key on. And anyway the engine stop too suddenly to be a fuel issue)

And I got a rendez-vous with my Nissan dealer, they are gonna check my ECU .

I'll get you in touch on the progress!

[oldsilvia-s12]

Ok some news!

The CA20E came with 8 spark plug, the 8 are firing 'till 4000rpm. At that speed, 4 of them shut down (dunno if it is exhaust or intake).

So now that I have no fire at all. It seem clear that it's really the ECU who don't want to send the firing signal. So the CAS and the EGI might be the source of my problem.

and today I'm gonna make an auto-diagnostic today.

Also, it will be my first auto-diagnostic, the ECU isn't OBD, it's simply a red and a green light. The code interpretation is written on the ECU but I wanna know how to run the auto-diagnostic. Is the car must be running? or simply the key ON? or it doesn't matter?

Fast answer will be please! still waiting for that to run the auto-diagnostic.
Modified by oldsilvia-s12 at 12:15 PM 5/21/2007

[johngriff]

The ECU on the 12 will either work, or it will not.

If you are getting break up after 4k, then the egi relay is providing power fine, it is a driveability issue.

Can you pinpoint this to 4k rpm, or this an issue only when the vehicle is warmed up?

If it ONLY happens at 4k. I would check the plugs for fouling and gap. All 8 Plugs will fire or they will not. They run off the same distributor, so not just one side will cut.

Otherwise, it sounds like the dizzy inside the distributor is either bad, or the advance is not working or hooked up. Its been like 3 years since i did anything other than rip a ca20 out of someting, then beat it with a sludge hammer, but I think some of them may be Vacuum advance, and other digital advance.

If, you have vacuum advance dist/dizzy then the vacuum probably isnt hooked up, or you have a leak inhibiting advance/retard.

If it is digital, then you may need to replace.

GO TO http://www.club-s12.org You will find the help you are looking for.

[oldsilvia-s12]

I've already posted on club-s12 about it.

And the engine run fine when it got fire. But when the fire decide to shut down, it shut down, no matter if the engine is idling, reving, or if I'm trying to start it..

Also It's can't be CAS issue, mine is a MKI and it don't have a CAS.

[Indecisive]

at 3 - 4k, 4 of the spark plugs are supposed to shut off.

At that point, the ECU cuts power to the secondary coil(one coil per 4 spark plugs) and runs on 4 plugs only.

As for your problem, it might just be the vacuum advance. If I'm not mistaken, the '84 - mid'86(black valve cover) models had vacuum advance while the mid'86 - '88(silver valve cover) had mechanical advance.

If you can get somebody to scan you a copy of the vacuum routing that may help.

Dunno if you got the answer for the ecu diagnostic or not but basically, you pull down the ECU, put the car to "ON" and then you simply take a screwdriver and turn the screw and it will go into diagnostic mode. Then just watch the flashing LED lights to get codes.

[johngriff]

lol, indy chases him all the way down here..

[Indecisive]

?? I don't get it...o.O

[johngriff]

You came from clubs12 to nico just to help this guy out. You are a nice guy.

[Indecisive]

ahha...that and I own a ca18det powered S12 and come to nico to check out this section a lot heh.

[oldsilvia-s12]

Thank you to come here to help me indecisive! Very appreciated.

Yes my distributor does have a vacuum timing advance, and the plug that come off from the vacuum isn't plugged no where. I've ask about it at a local performance shop and they tell me that it was that way on some car and that it's perfectly normal.

I've also ask my local Nissan Dealer and they tell me that it's because the distributor must have been changed and not installed properly. They tell me that I should bring them the car to let them take a look (wich mean towing to bring the car, + 65$/h on workhand, and no place for this until 1st june.)

If that plug is supose to be plugged, where should it be plugged? I've searched around it and didn't find where it could be plugged..

[Indecisive]

Thank you to come here to help me indecisive! Very appreciated.

Yes my distributor does have a vacuum timing advance, and the plug that come off from the vacuum isn't plugged no where. I've ask about it at a local performance shop and they tell me that it was that way on some car and that it's perfectly normal.

I've also ask my local Nissan Dealer and they tell me that it's because the distributor must have been changed and not installed properly. They tell me that I should bring them the car to let them take a look (wich mean towing to bring the car, + 65$/h on workhand, and no place for this until 1st june.)

If that plug is supose to be plugged, where should it be plugged? I've searched around it and didn't find where it could be plugged..

sorry, I don't have the MK.I FSM anymore. otherwise I would look it up for you. The mk.II's use a mechanical advance, and that's the FSM I have.

Ask on club-s12 in the ca20e section if you haven't already.

[johngriff]

If its just the vacuum advance, and he is not boosting (obviously), then it can go anywhere because it does not need a check valve.

So, hook it up to any vacum port on the intake manifold. If you cannot find one, ask ANYONE that has been around a car in the last 50 years, and they will find it on your car.

[oldsilvia-s12]

Ok I just did the auto diagnosis. No ignition code, it give me the water temp sensor and the air temp sensor. I doubt any of them can cause that. Next thing to check: EFI relay

[oldsilvia-s12]

Ok I've found the relay. I do have a MKII EFI relay in spare. they seem to be the same except the MKI is green and the MKII is blue ... :/ are they the same or they are different? ... XD damn i'm so newb in car electronic -.-