Loping idle and no power

[RLDaily]

OK, here's the deal. 1990 L98 133K miles

1st...I'm a licensed aircraft mechanic with about 20,000+ heavy maintenance hours on helicopters and fixed wing so I know my way around tools and stuff and I work on my car just like I would an aircraft, I have my tech manual open and I tag my parts...nuff said

I had a suspicion that the throttle body on my '90 L98 had never been cleaned and I was correct, it looked like it had bits of charcoal down its throat and when I removed it the backside looked like the darkside surface of the moon.

I cleaned the throttle body as described in "101 Projects for your Corvette 1984-1996" by using spray throttle body cleaner and a soft toothbrush and paintbrush...no scraping, scratching or anything like that. I also cleaned the ports on the plenum and they turned from dark brown/black to pretty aluminium.

I reinstalled with a new gasket of course (18 inlbs torque), hooked up the vacuum and water lines so on and so forth. Double and tripple checked connections.

The thing runs like a log wagon....Loping at idle and no power especially when trying to go into passing gear on the road...falls flat on its fanny...Oh yeah...fuel pressure 36-37 lbs at idle and open throttle.

Before I did this the thing would snap your neck going into passing gear and it was smooth at idle

 

[vetteboy86]

I have not read that publication. Does it call for cleaning the TB and plenum while installed on the car? I assume at least not the TB as you state you installed a new gasket. Did you clean the plenum on the car?

The fuel pressure should change between idle and open throttle. Did you hook the vacuum line back up the fuel pressure regulator? I sympathize with your position. It seems most things occur when during these types of tasks. Nevertheless, it rest assured it will be figured out.