This is on the '93

After the car is all warmed up to operating temp, If I slow down to turn or slow down at all to the point that my car will drop to 2nd gear during 1/2 to 3/4 throttle, I can hear the supercharger whine get louder then a few seconds later it will quiet down. Also, looking at the boost guage, it looks like it is dumping about 2 to 3 psi.

It only seems to do this when it is dropped down into second gear. I don't ever hear it at all when in overdrive, even if I stomp the go pedal the boost will stay around 8 or 9 psi.

So, from what I understand, if the pcm hears knock, it will pull timing and dump boost?

I don't have access to a scan tool to get any solid numbers, just my awesome description If that is what is going on here, what are some of the most common causes of KR on the * I?

Just mainly looking for some other things to check out when I get some time.
I already know about cracked manifolds, I have not checked them out yet...
I run 94 octane
fuel filter is less then 1 year old with only about 6 months of driving on it
NGK TR 55 copper plugs and AutoZone premium wires less then 2 months old

If anyone has any ideas, please let me know.

I don't think I'm understanding exactly WHEN this 'issue' occurs, but I don't see how you could have KR when you slow down or let off the gas. If you had KR at any point besides WOT I'd be worried. But you do need a scantool to be sure. Before I got a scantool I thought I had KR at certain points because of things I heard or felt while accelerating. Once I got one I tested many times and had no KR.

If you're running lean you can have KR, so vacuum leaks are a cause, fuel pressure problems as well.

happens in second gear at 1/2 to 3/4 throttle, but not at WOT.


EDIT: heck, even if it isn't KR, anyone have any ideas why I might just be dumping a few psi in second gear?

You need a scantool in order to figure this one out.

Yeah, I figured I might need one, I was just hoping to get some rough ideas.

There'* one for sale in the ebay section.