MrPickel

i have been looking all over this sight and others for my prob. i got my rx to start and run but she revs to 5500 on her own for about 90 sec and shuts off. iv been looking for a vac leak but could not find any. im about to pull the intake apart and go from there but if its not necessary... (i.e. timing is off by one tooth, something dumb) id like to know before hand. any info would be great. shes an 88, s4, 13b n/a, fresh rebuild from last owner. stock to the best that i know engine wise. however i found a greddy e-manage disk in the car but have not found the box it should go with. really anything would help at this point.

Pettersen

iTrader: (1)

What mod's have been done to the engine? Is the rat's nest removed, removed air pump etc...
If the timing where set wrong it usually just means the engine would run poorly or not at all.

To me is sound like some sort of engine management issue, but then again even with the bac wide open you shouldn't see 5500rpm without some additional air getting thru somewhere else.
Could be a buildt in safety feature that shuts the engine down, i tried running just two injectors on my Fc with apexi pfc, and it would shut down every time the coolant temp hit 50 Celcius, installing the sec injectors solved that problem.

First thing i would check would be the throttle body, make shure the idle adjuster screw isn't set to max, and that it operates as it should.

If the tb is good i would just tear down the intake, doesn't take too long. And make shure all the gaskets are good, and that it seals properly. That way you can atleast rule it out as an issue. At the same wime you can double check all the vacuum hoses and make shure that everything is as it should be.

MrPickel

to my understanding the engine is stock. but i found this disk in the car... (greddy e-manage engine control unit manager support tool) and im not sure what the air pump is right now, ill look up a pic of it after work, then cheak it out. i did find that the thermowax was damaged. it only had one vac line going to it. so i followed it and pluged it, i found another vac line that i think went to it and i pluged that to. no change. i did mess with the tb adjustment screws and no change. when its running i can get it to rev. i just cant get it down below 5500 rpms. if the ecu was replaced what would i be looking for? im so used to carb v8s... i just need to get the hang of this vac thing.

Pettersen

iTrader: (1)

The ecu is under the passanger footrest, so you need to take out the carpet, and to get the carpet out you need to take out the dash. So if i where you i would call the previous owner and ask if it had emanage.

MrPickel

i already did that and he didnt know. its a nightmare.

beefhole

iTrader: (29)

Pull the throttle body off. And check there isn't a screw driver jamming it open.
Unless that throttle is held open nearly 80%, the engine is not going to rev out to 5500RPM on a start up. You have a giant hole in your intake somewhere.