First of all thank you to all the repliers about my code 36 post. A new burnoff relay fixed the problem!!!

Finally I was able to look at mypanel without a bright yellow Service Engine Soon light on. I'm very proud of that!

But my 1989 convertible has more issues for me to solve and maybe thanks to your knowledge that would happen soon.

Here is the deal. The idle is not a "looping idle" anymore but I noticed it is a little higher that what it should be. It idles at 700 RPM, my understanding is that idle should be around 450 RPM. Am I correct on that one? Further more while at idle in neutral (I have a 6 speed manual) there is an On and Off rattle. I tried to locate the rattle but it's hard with the engine noise in the back ground, plus the rattle is not present all the times, it comes and goes. It seams to be located toward the bottom portion of the engine. At first I thought it was coming from a bad U-joint,(I can hear the rattle during engine braking too) but at idle in neutral I really don't think that's the case. Any idea where to start looking for the rattle?

Thank you for your time as usual!

 

I think I have that same rattle. I've been lead to believe that my throwout bearing is going. Anyone with some thoughts? Thanks.

 

Might want to check the serpentine belt tensioner. When the bearings on the small black pulley start to wear out, it can sometime rattle off and on depending on load.

I just replaced the serpentine belt tensioner on my 1990 Corvette as it had developed a noise and the pulley itself was starting to deteriorate. Rather than the pulley being flat across the load surface, it had deformed and was somewhat U shaped and the pulley was also somewhat eliptical shaped when viewed from the side. As a result, it caused the belt to ride off center and frayed the back edge so I had to replace it as well (about $55).

Unfortunately, GM doesn't sell the small black pulley by itself so you have to replace the whole tensioner assembly (about $80 or so).

Fortunately, it's a pretty easy fix to replace both the tensioner and the belt but I was amazed at how much stronger the spring was in the new tensioner compared to the old one.

Good luck...

 

Thank you for the hints. I did check the belt tensioner and everything seams to be in order. I have one more clue for you expert guys: with the engine NOT running and one of the gears in if I push the car back and forth a clunking noise come from the rear bottom part of the engine. I hope this will help you identifing the problem. Note: all the six gears shift very well with engine running or not. Thanks!