Hello,

I have rebuilt my engine and put put everything back together. When I try to start my car, as soon as it turns on, it revs up super fast and woud hit the limiter if I did not switch it off. Has anyone any idea what might be causing this? It is a stock, 1996 type rs with a power fc, Rotary Works throttle body and double throttle delete.

I am really desperate to find an answer.

 

Throttle body adjustment or insane vacuum leak.

 

Check you throttle position sensor

 

The rotary works throttle body does not have a bleed screw, but sits a little bit open when "closed". Should it be completely closed?
Also, how should I check check for vacuum leaks if I can't let the car idle?

 

On my pfc commander, the values seem to be alright

 

It should be almost totally closed

regarding vacuum leak tests:
Smoke test (leak will inhale smoke)
Or carb cleaner (will reduce idle surge, if you hit the leak with carb cleaner)

 

Idle speed is set by air going around the throttle plate. If the throttle plate is closed, no air gets to the engine and it can't idle. Stock you have the ISC that bypasses a measured amount of air around the closed throttle plates to set idle.

Throttle body open or a large vacuum leak will cause the problem. I doubt it's TPS.

I would start with getting the throttle plate to be totally closed or as closed as possible and see how you do. You may not have a "hands off" idle, you may have to use the gas pedal to keep it running.

Also make sure your throttle cable isn't adjusted too tight.

For vacuum leaks it will be anywhere air can get in between the throttle body and the engine. Check any block off plates, vacuum lines, and make sure the gaskets are there between mating surfaces of the manifolds.

Dale

 

Thank you Dale for your detailed answer.

How can I adjust the throttle cable? Because it is quite tight at the moment.

Also, can I safely remove the LIM with the engine in the car? Might as well check there right?

 

Stock the throttle cable has 2 12mm nuts on a threaded portion. You sandwich the throttle bracket between the 2 nuts and tighten them both down to lock the cable in place and you can also adjust tension by loosening the nuts and changing where they are tightened on that threaded portion. It's pretty straight forward.

I don't know if that throttle body uses the same bracket or how it's set up.

You should have a small amount of slack in the throttle cable with the throttle closed. If it's tight, that means it's pulling open the throttle plates most likely.

Start with that before going further.

Dale

 

Thanks to Dale,my car is now working. It turns out, that even if the rotary works throttle body is only opena little bit, that is enough for the car to rev up a lot.

I was doing the idle learning process but had to stop doing it it because a big amount of smoke came somewhere around the turbos. Is it because my downpipe is freshly wrapped?

 

Thanks to Dale,my car is now working. It turns out, that even if the rotary works throttle body is only opena little bit, that is enough for the car to rev up a lot.

I was doing the idle learning process but had to stop doing it it because a big amount of smoke came somewhere around the turbos. Is it because my downpipe is freshly wrapped?

 

It's possible. New exhaust components will almost always smoke from greasy handprints and junk on them. As long as it's not a leak of some kind you're probably OK.

I know it by smell, there's a smell of new engine/turbos burning stuff off.

Dale