rough idle, stall, misfire

[illinest]

stock 90 gst, we have replaced the plugs, checked the ignition coil, and just got a repaired ecm back from forum member Steve.
Car USUALLY starts, (we have had a few occasions where it just turned over for awhile) it runs rough, and will occasionally stall out completely. We can hear a clear misfire through the exhaust, irregular, sometimes as fast as 1 per second. We are also missing power.
I would like to screen some ideas here on what to check next, and get suggestions if you know of something that I haven't thought of.
Plug wires?
Fuel injectors?
Idle Speed Control?
ECM still jacked?
Timing somehow screwed up?
Loss of compression?

Please let me know if you think any of those components might cause the symptoms we are getting, and add to our list if there is anything we missed. Thanks in advance.

 

[jasoncitrano]

stock 90 gst, we have replaced the plugs, checked the ignition coil, and just got a repaired ecm back from forum member Steve.
Car USUALLY starts, (we have had a few occasions where it just turned over for awhile) it runs rough, and will occasionally stall out completely. We can hear a clear misfire through the exhaust, irregular, sometimes as fast as 1 per second. We are also missing power.
I would like to screen some ideas here on what to check next, and get suggestions if you know of something that I haven't thought of.
Plug wires?
Fuel injectors?
Idle Speed Control?
ECM still jacked?
Timing somehow screwed up?
Loss of compression?

Please let me know if you think any of those components might cause the symptoms we are getting, and add to our list if there is anything we missed. Thanks in advance.

My buddies car has the exact same problem. When it is running do you have problems with it cutting out at high RPM's?

Have you taken a look at the cam angle sensor, that made it a little better for us.
Recheck the timing, don't use a logger, use a timing light.
Check caps on ecu unless u just had em replaced but i'd check for leakage anyways.
Our next guess was going to be possibly the fuel pump.
We have replaced the injectors, plug wires, Power transistor, coilpacks and checked compression. hope this helps.

 

[illinest]

actually from listening close, we think we are hearing the sound of a relay going bad. fuel pump relay?
thatll be our next check.

 

[ddavisaf]

It's a possibility. What kind of spark plugs did you put in and what are they gapped to?
Also check for a boost leak as this will cause the same symptoms.
From there test your injectors and fuel pump.
After that look at the ISC.

 

[illinest]

this one is going slow and I thank everyone for their help
new update.
key turned, engine turns over but doesnt start.
leave key in ignition to perform a voltage check on throttle position sensor
while im in there i hear a short rattle, (clik clik clik clik clik clik) That sound like relay struggling to close to me.
on a hunch, i run to the ignition and turn the key. Car starts. I am one hundred percent sure that the rattling click is the deciding factor in my car not starting, but I cant tell what it is thats rattling.
I had my brother turn the car on and off while i listened, and when I COULD get the noise to replicate, I could only isolate it to the back of the engine compartment around the area of the intake manifold.
I did tests on the ISC and all of my resistance values came out SAT. I have not yet been able to run the voltage test as outlined in the manual to verify that the pintle is moving, but I believe the ISC is good.
I did tests on the Throttle position sensor, and my values there were good as well.

 

[jasoncitrano]

Our's did the same exact thing...with the clicking. It's right under the intake manifold but you can't pinpoint exactly what it is. One day it wouldn't start at all and all you'd hear was that clicking. Still not fixed yet.

 

[illinest]

well thats two of us then, this must have come up for SOMEONE before ey?

 

[jasoncitrano]

We were thinking mabye it could be the coil pack but not sure why they're clicking also it's on the opposite side of the coil packs is your's clicking there too? It's a really wierd noise isn't it like a few fast clicks then a slow one then a few fast.

 

[illinest]

well we pulled the coil out and did resistance checks which turned out sat.

 

[jasoncitrano]

Only other thing down there would be the starter solenoid?? What about possibly a bad solenoid?

Only thing i don't get is why it does it with the key in but the car off.

 

[illinest]

turning the key to the on position "preps" the engine for start, is the starter solenoid down there? I can't see why that would make me stall though....
perhaps the rough idle and stall is seperate from the "not starting" problem

 

[sstaylor]

I know I am still a newbie but I had same problems and finally got it through my head to make a boost leak tester and found all kinds of boost leaks. Just a thought but give it a try.

 

[GoldenBoy42]

I have made a tester and done a boost leak test on the car. There are many leaks im sure, but the only one i can tell for now is the IC, too much air is coming out there to really pinpoint any other ones. Either way, before the ECU crapped out on the car, the leaks were still there, but there wasn't any problem with the idle. Those leaks will get fixed, but I don't think it's the source of the problem and I'm short on cash. What DSM owners aren't after all?

 

[megadan]

From what I heard, I can tell you that the clicking noise is certainly the PCV valve dancing with the engine . Put your hand on the hose to the valve cover near intake manif and start the car (or try in your case) your going to feel it.

 

[ddavisaf]

Where are we at with this problem now??

I'm lost.....

 

[jasoncitrano]

Well illinest and I are having very similar issues. Both experiencing crappy idles, bogging, stalling and in my case even no starts.

Also there is a clicking noise coming from the rear that happens right after you try cranking the car over a few times for me. thanks

 

[ddavisaf]

MFI relay has been a problem for some. Ignition related components for others. Problems with fuel have been experienced also. Not to mention sensors being faulty.

And lets not forget about the caps in the ECU.

Key is to find which components are faulty in your system.

What have you replaced, what have you tested, what are you running (plugs, pump, injectors, etc...)?

 

[ddavisaf]

http://members.shaw.ca/costall/1000Q/answers-problems.htm
Read over this, it will help.

 

[jasoncitrano]

Alright did a little bit of research. Found out what the hell was clicking like crazy. There are actually two things clicking one of them is the purge control solenoid valve. located right on the firewall. The other i'm assuming is the purge valve itself on top of the charcoal canister.

What could cause that to click like that?

Any way this could cause a no start condition?

We realized we are not getting spark now, we have compression and fuel though. Timing marks are lined up. But no spark.

 

[ddavisaf]

Test the coil packs and ignitors. Also, make sure your CAS is good.

 

[jasoncitrano]

Test the coil packs and ignitors. Also, make sure your CAS is good.

CAS is good. only thing i'm kinda puzzled on though is theres no spark on any cylinders. WHich would make me think it's a bad triggering device (CAS)
What's the procedure to test the ignitor and coils? for the coils should i just check the resistance accross them? any idea on specs for them as well thanks alot for the help

 

[ddavisaf]

http://www.dsmtuners.com/forums/showthread.php?t=196152&highlight=coil+pack+resistance
See if that helps.

 

[ddavisaf]

Ignitor is also called the transistor pack I believe.

 

[jasoncitrano]

That helps with the coil but what about for the ignitor?


Also what would cause the vent solenoid to keep clicking with KOEO and even when the keys out of the car it clicks.

 

[jasoncitrano]

Anything?