Ok, so I am trying to trouble shoot my friends car... Its an engine swap into a 64 impala wagon here are the basics..

Engine and trans out of a wrecked 92 Camaro. 350TPI with 700R4.
Large tube runners, BBK large bore throttle body. Painless wiring harness.

This project has been 10 yrs in the making and finally got it running last year but the idle was high... Got some exhaust and stuff fabbed up, misc wiring tidied up, tried to sort out the idle... So far we have been unable to find a vacuum leak. TPS is .57 VDC.. car revs great. Timing is 6BTDC.. We are getting a Code 42 but I think its due to fast idle.

Biggest problem is the car is 6hrs away from me, so I am playing phone tech with my buddy.

Today he clamped off every vacuum line no change. Unplugged the IAC plugged the IAC holes no change. Then he clamped off the MAP sensor vacuum line and the idle dropped to 450rpm... unclamped the line back to 3000... Unplugged the MAP wiring the RPM drops to 450.... ??

Any ideas?

here is the car... and thanks for any help... I am going crazy..



Thanks,bill

 

Monday bump. Any ideas?

 

Has anyone seen anything like this with the MAP sensor? It is a brand new unit. I thought if you unplugged the map the car died?

 

Bump...
Can anyone answer about the MAP? Should the car engine die?

 

I am the Guy that the OP is talking about. I bought and replaced the map sensor and it didn't make a difference. The map sensor was mounted under the dash and I moved it out by the intake and uses a vacuum hose less then 6" and still no change.

 

bump. Can anyone point us in the right direction?

 

That is faster also a good online store for performance parts is www.fasterthanthem.com