Hey guys, need some help. Recently replaced my engine and did full non-seq turbos. Everything has been running good except I have had a hard time figuring out the idle. Adjusted tps, and other screws, and reset the pfc and got no changes fixing idle. I also decided to clean and lubricate the ISC and in the process forgot to bolt it back onto the UIM, when I started the car the rpm's shot up quickly by itself and I shut it down as quickly as possible. I realized how dumb I was and bolted the ISC back up and tested it out again, but not only was the idle still rough I seem to have some power/boosting issues.

It is hard to explain what exactly is happening, but when you accelerate there just seems like a lack of power, and the psi doesnt climb as steady as it was before. I checked the turbos and found no end play and no oil. I ended up finding that my vacuum line for the stock bov was melted. I replaced it, drove it around came back and it was in the process of melting again. Never had an issue with that as its not sitting on anything just travels across the y-pipe.

Dont really know where to go except maybe a compression test... Any help is greatly appeciated!!

 

Drove it around again, getting harsh stumbling on acceleration to clarify the symptom. seems almost like the map sensor is messed up, but no back firing or anything else.

 

Are u making any boost at all? mine is kinda having the same problems. was fine two weeks ago and BAM.. only .2 bar boost, very harsh stumbling revs and wont go over 5thou revs, and even that is an effort. Havent had much luck on this forum so im gonna get a snap on diagnostic tool hooked up to see if that can tell me the prob.

Let me know how u go, and i'll keep in touch.,

Good luck.

Dave

 

Hey thanks. Ya I can get full boost on my gauge, it seems to spike really fast though and it stumbles all the way up.

 

So I did a compression test with a piston engine tester on a cold engine... Rear rotor 120psi, front rotor 95psi. Difference is 25psi, which would probably explain my problems. I just find it real hard to believe this would come about by just leaving the ISC removed by accident, on a engine with less than 5k miles on it.

Any thoughts? thanks

 

sounds like a rebuild to me hey.. bugger..

 

is your boost gauge bouncing around while you accelerate?

 

No it doesnt bounce, climbs normally. The engine just stumbles as it accelerates.