I had a guy who works at the Mitsu. dealer look at my car today for this problem I've been having where it bofs down if you floor it from idle to around 2500. The thing is the car doesn't have any error codes at all. And here's the ticker, he has 2 more sitting at the dealership and they don't know what is wrong with them. He said they have even called their tech lines and can't get any help on it. One has been there for 4 weeks and they still can't find the source of the problem. They have even pulled the head apart and replaced the pistons on it. So it looks like I get to be the 3rd one they've ever seen do this. He said they're going to tear it apart again on Monday and if he finds out anything he will let me know. He said there's some type of vacuum leak somewhere and the car only bogs when you punch the gas. Other than that it drives/idles like normal. Just wanted to pass on some info. to see if anyone else has experienced this.

probably running rich .. check the injectors. I've seen stock injectors CRACK on cars that have never ever had them touched. Crazy.

you know i have been meaning to ask about this for a while now. this post sound like it might be related. whenever i get on the gas around 2500rpms the engine makes what sound like a rattling noise. i though it might be a loose bolt or something simple like that but i cant find anything loose. i've never heard detonation in a car so i thought it might be that so i changed back to the stock plugs thinking they might be too hot. but no change. the noise is also accompanied by a small loss in power i think (but i might be amagining that). so that makes me think detonation, and pulling timing. so i am trying some 93 octane gas to see if that stops it. what do you guys think.
-Josh




weapon-r intake
greddy headers
apex-i n1 catback
afx udp
energy suspension
motor mounts
cf altezza tail lights
bored t/b
magnecore wires
hotter plugs

You are right about it running rich Darkone. The exhaust is black and you can even smell it. If an injector was cracked wouldn't it set off the CEL though? What it would do is either bog down or backfire when you stomp on the gas and it mainly does it when the car is close to idle. It will do it if I'm running up to around 2500rpm but I have to be in gear and trying to move for it to happen then. I also noticed that if I put the ngk plugs back in it will backfire and bog down more easily with those plugs than it will with the bosh platinum 4's which I still have in there now. I thought about getting the induction cleaning done but the guy said that probably isn't the problem(I'm still going to get it done anyway). He said to check and see if the cat is clogged causing me to backfire though.

Has anyone had this problem before? Could it be a problem with the throttle body or intake manifold?