I screwed up somewhere and may have done some damage to my evo. I'm not sure what to do next so I could use some advice.

I have an '03 with buschur's stage one kit and reflashed ecu (mail dynoflash). It has been running fine and I wanted to go to stage two which includes new upper intercooler piping and hard intake pipe. I spent the afternoon removing the old piping and installing the new. When I was done I double-checked that all the connections were tight and went out for a test drive. The car was runing well and behaved perfectly normal during light excelleration.

Then I decided to give it a go in 3rd. Acceleration was smooth and I was watching the boost gauge to be sure I didn't overboost when there was a sudden bang and loss of power. I immediately put in the clutch and let off the throttle and the engine died. I pulled over thinking that one of the hoses had come loose but couldn't find anything. I then started the car again and the idle is very rough, idling up and down between almost stalling and about 1100 rpm. If left alone, the idle will eventurally even out a bit but still seems to be fighting to keep from stalling.

The CEL came on immediately following the bang and I pulled the (one) code: P0121 -- Throttle position sensor. I managed to get it home but it has no power and won't rev above 2000 rpm or so. Looking at my wideband, it's running really rich somewhere around 9.4 AFR at idle. I haven't had a chance to look at everything yet because I'll have to jack it up to check the connections at the intercooler itself. Assuming I don't find a leak, what else should I look for?

What the heck could I have done? I'm going to pull the plugs to see if one or more is fouled but seems like a longshot. After the car had cooled for a few hours I started it up and it idled well (albeit rich at about 11.2 AFR) but as soon as I touched the throttle it tried to stall and went way rich as I said above.

 

did you reset the ecu?

 

have you checked your intercooler hoses/clamps??? Go look at your throttle body right now.

 

You need a new tps sensor.No big deal.

 

Yes, I reset the ecu both after the install and after the "incident".

I've also checked the intercooler piping and can't find anything loose. However, the connection down at the IC itself I can't really get to right now. Everything else seems ok.

 

I sure hope you're right. It does seem odd that it chose just that moment to go bad though.

 

i've had this happen many times, it sounds like you blew a vacuum line, this would cause your car to not rev over 2000 rpm, stall, bog, it sounds like you blew a hose, a clamp isnt on tight, check all intercooler piping, if you were under boost and you heard a "bang" the odds are your piping is whack, id bet $25 thats the prob

 

Sheesh. I'm pretty sure I found it! That lower connection that I couldn't quite get my hands on came off when I was tripple checking everything. That's gotta be it. I'll have to wait until tomorrow but I feel much better. I've read other stories where the car had the same symptoms and it was exactly the same problem I just couldn't find the loose connection.

Heh. I'll sleep better now.

 

Same thing happened to me, or at least, same sounding thing, it was one of the intercooler pipes coming loose, I've heard of it happening to a lot of guys cuz the stock clamps dont hold very tight

Though, I panicked too, and being that I don't know jack about working on cars I just had it towed up to the dealership, and they had it fixed within like 10 minutes of getting the car on the lift, and tightened the clamp as much as possible...may not be what's wrong with your's, but just incase anyone else looks here

 

I had that same problem but surprisingly it didn't throw a SES light... Good thing it was just the hose that connected to the TB... It was a pita trying to find the hose clamp in the engine bay without a flashlight...

APC has these fancy looking clamps that look like they may hold better than the stock clamps. The only thing is they're semi-ricey (depends on your taste) and cost twice the ammount for the "T-bar clamp somthing" (SP)... The kind you find on turbo diesel vehicles...

To be cost effective, a trip to home depot to get nicer hose clamps and I guess just keep spare clamps and a screwdriver in the car...

 

I just had the exact same thing happen to me today. I've had the BR stage 2 kit on the car for about a year and a half with no incidents. I was passing someone on the freeway and I heard a pop and it died then when I restarted it, it could not rev above 1700 RPM. It threw P0121 also... I guess I better check the hoses, because my PocketLogger says TPS looking fine. All of those hoses look tight, but I didn't pull on them because the motor was hot and now I have a headache from exhaust fumes...

(update)
I just checked it out and all of the connections you can reach from underhood seem fine. Maybe its a connection on the intercooler? Or maybe something else (electronic) is wrong with it. Now I don't know what to do...

 

Holy thread rivival !!!!

Check your lower IC hoses/piping. Gotta be it.

 

I found it. The stock rubber pipe that connects the driver's side of the IC to the first segment of pipe to the throttle body came undone. That thing was really hard to get back on. The stock rubber piece barely fits over the pipes. And then there's the undertray....

ugh..

 

Whoa! A blast from the past!

Yep, driver's side connection on the IC was what came off for me too (if I remember right). It's a pain to get to, especially if you're stuck on the side of the road. Luckily, even though the symptoms make you think you've destroyed your engine, everything is good again once you get the pipe back on.

 

check your lower intercooler pipe if u havent already this happen to me wen i mine on i didnt tighted it enough and then i was driving hit full boost and BAMM heard a loud noise is scared the crapt out of me. so i stop the car pretty much shut off. look under my car and see my lower intercooler pipe just haning there. lol just double check all the couplers and the clamps! thats my only thought gl.