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turboEclips

20+ Year Contributor
76
0
Aug 5, 2002
TX
I have been having a reoccurring problem with cylinder 1 misfire until tonight i got the random/multiple misfire CEL. i already changed my plugs and wires AND it still keeps happening. After i get the misfire code, it runs all rough kinda poppy. When i got to the stop sign after getting the code it was idleing all crazy like it was fixing to die.

I have been having this problem off and on. But it used to alway just be a cylinder 1 misfire, this time it was PO300 multiple/random. is it a bad coil?:confused: or is my motor focked... :(
 
if you are worried about the motor do a compression test. This will tell you if it is ok in less than 30 mins with only one person.
 
i'm going to check the compression tomorrow. how would i know if the coil is bad? is there a way to check it?
 
The easiest way to test a coil w/o a scope is to test it on the car.

1) Disconect the plug boots from cyls 1 and 4, and insert a 5/16 X 2 in bolt all the way into each boot so that it touches the metal clip inside.

2) Lay the plug boots (bolts inserted) on a piece of insulating material (dry wood works well) spaced 1/2 in apart, so that you can watch them as someone cranks the engine for you. The spark should easily jump the gap as the engine turns over.

3) Repeat test for cyls 2 and 3.

Notes: ** DO NOT touch the wires as the engine is cranking.
** If the engine starts during this test, turn it off immediatly to prevent fuel buldup in the engine and setting more misfire codes.
** This test will not detect intermitent failures in coils, and is intended as a go/nogo, internal short, and max output test.
** you can use an ohmeter to test the primary and secondary coil resistance. I'm sure someone here has the specs...

That being said, it sounds to me like your EGR valve is sticking open. A sticking egr valve will set random cyl misfire codes on OBDII cars (late model DSMs) and give your engine an idle like a top fuel dragster... simple test; disconnect your egr vacuum line and plug it (2g still vacuum?). Then drive a few days and see if it still screws up.

There are a milion other things that can give these symptoms. Can you give any more details? Can you feel the misfires? How often? Are you down on power? How long has this been going on?

my 2 cents
 
SORRY IF THIS IS LONG...

what exactly do you mean by "The spark should easily jump the gap as the engine turns over." i must sound like a total noobie by asking this.

before i get the code, i guess when it is misfiring it feels all sluggish.... it seems like i am flooring it, and it will not go at full power. sometimes i can tell from the tone of the exhaust/engine. last night i was out because had just install my dumped O2 housing, and it didn't happen once. other times, i just barely get on it through 2nd or 3rd and it comes on. i don't think i mentioned this, but it only happens when i'm getting on it.

it is weird i had been running 20psi for a while, and then this started happening, but if i turn the boost down to 15psi, i don't seem to have a problem with the misfire CEL. I haven't really had a chance to tune it because of things that keep happening, but i have the afc settings at -30 across the afc and my egts only go to around 880.
 
Do you have 1G CAS or stock CAS? You might have a bad CAS that sends the incorrect signal to ECU....
 
i guess i have a stock CAS, i have never messed with that, nor do i know what it is.
 
well my friend did a compression test on my car and these are the results...
1: 195
2: 170
3: 180
4: 185

according to him those are decent #'s. Anyways today my car started f'ing up even more.....It is smoking like crazy when i get on it. The smoke is white, but the funny thing is that it doesn't seem to smoke when i'm on it. When i let off the gas is when all the smoke comes out. IT IS BAD!!! :(

Since my compression was OK... we checked my oil to see if there was any coolant in it...suggesting a blown head gasket... but there was none. What is the deal :confused:. My friend was saying that i could have bent a valve and that it would cause this and the compression would be fine.

Any Suggestions?
 
a bent valve would kill your compression readings so i doubt this. Also white smoke is oil i believe and a bent valve would not necess let in oil. I would check the turbo if i were you. It if very possible that the turbo is leaking oil or water into the intake system and that is what you are seeing. Do you loose oil or water over time?

When the car is smoking put a cold wet towel into the exhaust path for a few seconds. If you pull it away and put it in a bucket of water and there is no oil schene then it is probably water from the turbo lines.

Do this only at idle!!!!!
Take the water lines off the turbo and idle the car for a very long time (make sure you plug the lines so water doesn't come spilling out. If the white smoke goes away then the turbo is leaking water. The same thing can be done with the oil lines to the turbo.

Yes those compression numbers are ok but a 25psi difference isn't good.
 
it doesn't smoke when it is at idle, it only smokes after i get on it, and let off the gas.
 
anybody got any ideas..... :confused: . somebody told me it could be my turbo, because it only smokes after i boost it :cry:. is there some kind of test or something that i can do to tell if it is the turbo???
 
hm...smoke when u get off it with the car still in gear and clutch still engaged? If so, that sounds like worn exhaust valve seals to me.
 
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