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cylinder misfire? HELP IM LOST!


churrbo98
03-17-2008, 09:30 AM
OKAY everyone. I have a 98 eclipse GS-T and I am having a misfire problem. Here we go. I have tried the following things. replaced BOTH coils packs, replaced the spark plugs, replaced the wires, replaced the ignition control module. Than began to think i may have a burnt valve so i did a compression test, 150 across the board.... blows my mind..... cylinder 1 and 4 are firing but 2 and 3 are not. like i said IT BLOWS MY MIND!!!! Any ides on what this might be? ANY HELP IS FANTASTIC!!!! DISTRAUGHT DSMer

CaliCartel
03-17-2008, 11:09 PM
Wow! Wierd, 150 across the board, I would think it was head gasket torn between 2-3 leaving you with a compression leak, did you try a WET compression test? to check piston rings. If so maybe control module is bad.

churrbo98
03-17-2008, 11:15 PM
yeah? why would you think that? I have no leaks. Just no spark and the only CEL code that comes up is multiple cylinder misfire. Yes ive replaced the ignition control module.....

steviek
03-17-2008, 11:44 PM
you know what you should try. Swap your plugs from 1 and 4 onto 2 and 3 and see which cylinders fire. As long as your timing is zeroed and you are just idling this will not hurt your engine at all. I just want to see if the signal is getting through on your other cylinders (2,3)
Or you can just pull the plugs and see if they all spark. This will greatly narrow down the problem area. (either before coil pack or after)

churrbo98
03-17-2008, 11:49 PM
I have dont a test to see if im getting spark from the coil to the plug... nothing to 2 or 3 before the pack im not sure though quite yet! Switch plugs or wires? both are new either way.... im kinda down to the filthy few!!! :2cents:

churrbo98
03-17-2008, 11:52 PM
My last few ideas are the power transistor, CAS and finally the ECU.... like I said, the filthy few! haha! What do you guys think?

gthompson97
03-18-2008, 03:27 AM
See if you can take it somewhere to get the injector pulse checked, you may have a dead injector that's not firing.

churrbo98
03-18-2008, 07:51 AM
hm... to be honest, what would the injector have to do with spark? People when leaving your reaponses please include your reasoning... If I had money to waste I would have had it up to Mitsubishi by now!!! :2cents:

gthompson97
03-18-2008, 02:52 PM
Nevermind, I didn't read the posts very well, I thought you had a misfire and couldn't tell from where, my bad.

Prime First
03-19-2008, 09:23 AM
I had the same problem with my 99 GS. I was getting so frustrated because I couldn't figure out what was causing the misfire in cylinder 1. I also thought I had good compression. But after an eternity, I sent it to the dealership who found that my compression was actually around 70. Turns out the cylinder head had to come off.

This may not be your case, but always worth another shot! How did you check the compression?

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