Hey Guys,

Time to ask for your opinion on the following -

Can excess wear in the butterfly cross-shaft (which I believe that I have)cause my Tpi to set the SES light? Car as 64,000 miles.

My Tps and Iac are set to spec (and are both new) and idle is 600 in Drive and 750 in Park.

Just trying to eliminate some ideas that have been suggested to me.

The car runs fine once fully warmed up but like a bag of cr*p from cold - idle problems, surging, nearly cutting out then magically clearing itself.

I do get a Code 51 but no codes associated with a potential Tps problem.

I have a new PROM so maybe the ECM is dying?

Anybody got any ideas?

Thanks.

 

Well by your handle i gather you have an IROC, and since 90 IROCs are relatively rare i'll take a shot in the dark that you have MAF. And if you have MAF, then yes, excessively worn throttle shafts could cause a reasonable vacuum leak, prolly enough to anger the MAF / ECM.
Do a search, i remember this topic coming up not too long ago and it had a source/procedure for re-bushing the shafts.

------------------
Ed Maher - Moderator @ The TPI & Carb Boards
92 Z28 Convertible - Quasar blue / Tan top
305 TPI A4 2.73 - 14.7 @ 93.6
Stock except ported plenum and dual cats
-=ICON Motorsports=-

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

Yep, I think you know what the problem is. I would try a different ECM if you can.

 

Thanks for your reply Ed,

I have an '86 Iroc with a MAF sensor (Well I think that is what it is!)positioned between the Throttle Body intake and the Air Filter ducting.

The wire appears to be okay and the mesh screens are in position.

I will check out the re-bushing procedure and try an ECM from a known good vehicle.

Thanks for your comments.