supraturbo1987

iTrader: (4)

Okay, I have the voltages where they should be on the TPS. Car still idles a little high even after completely closing the air adjustment screw under the elbow. So, i set out for a vacuum leak...one of the vac lines was off of one of the turbo wastegate selenoids which is right under the black plastic chamber in front of the UIM. I replaced that one. Now, under the black chamber is a vac line that goes to a small checkvalve, then from the check valve goes a short distance to a hardline...follow the hardline and another vac line goes to some other check valve with like 5 hoses on it. Anways, that whole route had no vac lines...the check valve had one line going to it, but it breathed to the atmoshpere on the other end...did not have another end of the checkvalve. All of the associated hardlines were capped off and the check valve was vented to the atmosphere...is this correct?

I am getting terrible missing/backfiring on decel after I rev to about 2k...if i hold the idle steady at 1500, it intermittantly will dip down to 1100, then back up to 1500 and repeat until i let off the gas....does the same thing if i hold it steady at 2k, it dips to 1500 and up and down up and down. I wasn't sure about that check valve route, so i completed it. The checkvalve is made of to plastic ends which each have a vac line coming off them...i only have one end of the check valve, and it was venting to the atmostphere...so, i removed the checkvalve and just made it a straight vacuum hose passage and completed the route that was once capped off.

I am guessing that since I have the air adjustment screw closed and I idle at oper temp at 1100, there is still more vac leaks...or is it because i removed the check valve?

Trev

dgeesaman

iTrader: (7)

IME, a single check valve or open vacuum line doesn't do much to affect idle.

Dave

supraturbo1987

iTrader: (4)

okay, so there still must be a vacuum leak somewhere. If one hose can be cracked and falling off, then more can. This car has a silicone hose job, but I think it was done years ago and needs to be re-done again. What other things can cause this? ISC?

Trev

supraturbo1987

iTrader: (4)

okay, figured out that the check valve only has one end because I am a M/T not an auto. Still searching for vac leaks though...

Trev