84 crossfire problems

[thlew61]

I bought a crossfire Vette and it has problems I cannot diagnose, nor can any mechanic in my town. If anyone knows this system, I could really use some help.
Problem: Previous owner broke the seal on the front throttle body to adjust the fuel amount/intake. The engine idles at 13000 rpms and it wont idle down. It loads up and dies each time I try to set the TPS on the rear unit. I put a 86 fuel pump in, rebuilt both bodies but did not replace the IAC in front unit. It has started to back fire from both throttle bodies now. I replaced the catalytic converter without results.
If I use the Xram, I still need to dial in the throttle bodies, which takes me back to point A.
Any suggestions?

Thomas

[thlew61]

Problem fixed...noone had even a hint?

[89IROC&RS]

did you run it for error codes? im pretty sure that car had an OBDI system on it didnt it?

but it does sound like it was a vacume leak of some sort, or the IAC you didnt originally replace, but this is kind of moot seeing as you already fixed it, care to share what ya found so we can learn from your problem?

[thlew61]

There was a vacuum leak under top plate to plenum, oxygen sensor was bad and they recalibrated the front throttle body with the rear unit. Yes, the 84 is capable of showing error codes but they were directing us to false problems. A man that used to build them at the plant helped with the fix. Always look for vacuum leaks under the top plate first.

[walkwalker84]

I had problems with mine also. If you adjusted the screw on the fuel regulator you are going to have problems. The specs are set at the factory you can't adjust without a special tool. when I adjusted mine I had the same problems. I finally corrected the problem through trial an error. also you may want to get a rebuild kit only about $30.00. I may be wrong about the fuel regulator, but before I spend a bunch of money on other things I would check it first.

[89IROC&RS]

thanks, ill add that diagnosis to the vault

[cuttingedge]

check your throttle body gasket my blew on my vet and did the same thing..

[thlew61]

I did, no effect but thanks. Im tired of working on this crossfire so in a few years I might try it again.