R33 Rb25det Running Very Rough

[Kujotk]

Tonight i started my car to leave work at midnight and the car was shuttering and shaking, when i accelerated slowly it had noticable allot less power and it sounds like a WRX engine now comming out of the exhaust.... i pulled over immediately and found that there was a wireing harness that was not connected to anything that was previously connected before i took the car to get new spark plugs and a clean out of the throttle body (i think its the throttle body), so i reconnected this harness. this brown wireing harness sits toward the back of the engine bay on a brass looking cylindrical tube that seems to be sitting behind the plenum and may be connected to what i call the throttle body. There was no difference reconnecting this wire.

What is this wire used for and how is this related to the problem i now face? I have provided a picture of the wire that was found not attatched...

When i decellerate in gear the engine sounds normal and the car is smooth again... when i accelerate the car shakes and shutters and there is not allot of power, the exhaust seems to smell like something burning but the engine temp that is on the dash hasnt risen more than normal that is somewhere inbetween a 1/4 - 1/2 way up the temp guage,,, also my own temp guage that i have put in the engine bay has not risen above normal either...

please help..... this prob is the last thing i need right now

[Kujotk]

i have just completed some forum searches and i think it may be the coil packs or the afm, seeing that both were played around with on the weekend by the mechanic and there seems to be allot of people in the past who had similar symptons as mine..... thank god i hope thats all it is and not the engine itself..... but i still want to know if anyone else thinks it may be something else, also i still would like to know what that wireing harness above is for.....

cheers

[trel]

Looks like a connecter near your aac valve. Double check that all connections are on good and proper. Also if your spark plugs were changed, check on the back of the engine where the plastic spark plug cover ends, there is a connector there which goes into the black plastic cover make sure thats connected properly. Only other thing I can think of is maybe your coilpacks have not been put in properly after he did plugs or your intake piping wasnt put on properly, which could possibly cause your rough running. Don't stress I got the same thing after I changed my plugs and i just re-checked all connections made sure everything was tight and it went away.

Cheers,

Evan

[Kujotk]

ok pulled the engine appart and had a look, seems that the guy i got to change the plugs didnt clip the coils in all the way..... also thats the last time i get someone else to do something simple on my car....

car is back to normal

thanks evan