I'm about to buy a '90 s13 w/ a redtop sr. Hes had the car with the swap for a couple years now but hasn't run it at all in the past monther and barely driven it the past year.

He started it up and it idles really smooth, runs really rich but revs ands idles smooth after warmed up. Problem is, when i let off the gas, coming to a stop or just slowing down, the car will just die. He hasnt run the car in a month or so. He said it used to do that but not as much as it did tonight. Everytime i would slow down and let the rpms drop it would hit 0 and shut off.

It's not a recirculated bov, so that could be some of the reason it dies down, but it happened every time. Could it be the plugs? Or what else, considering it wasn't run in a month and he barely drove it before that.

I'm about to buy this car but i need to know if there is something seriously wrong with the engine or if is just minor adjustments that need to be made.

Thanks, Greg

 

BOV. It could be set too loosely, or sticking/slow. Try to adjust it to be tighter. The quick 10-second troubleshoot would be to unplug the vacuum line and cap it off.

Other outside chances are leak injector/seals and vacuum leak. If it idles smooth, it's most likely not the IACV, which is a common misdiagnosis.

 

like epstein said, adjust the bov that might be the only problem..

 

i have a feeling it could be that ...ive never owned an sr before, but its runnin 11.5 psi and i can hear it blow off a little at 3k rpms...seems a little too soon so maybe needs a tightening

 

Check out the throttle. The adjustable screw thingy might be set too low, which will cause the throttle not to open. If its get no air to breath, the motor stalls out. Check the cable while youre at it too

 

ya could be that also..but its weird because the other day it didnt do it everytime. sometimes it would drop to 100rpms, then recover.

It idles perfectly fine when started up, so would that eliminate the throttle being too closed?

 

check the bov

 

cant right now..cars at the guys house...but i will when i take another look at it...

 

I had that problem too. It turns out to be the throttle being closed too much. Set it at 1k rpm, and drive it around. Like you said that it idles just fine, but once you get behind the wheel and drive it around, then come to a stop light, the RPM drops down alot to 100, recovers sometimes, or simply stalls out.

 

ImportLuv, your throttle plate problem is a variation on the IACV thing that I mentioned. The throttle plate on a normal swap should be closed super tight. So tight, infact, that it's water tight (tested with actual water!). You could have simply adjusted the set screw on the IACV, which lets air around the plate (through that nearby 5/8" hose). Again, I don't think that improperly set idle adjustments are the cause, but merely exaggerate the actual problem.