fixing someone elses problem...arrgghhh

[Below Ambient]

ok so i bought my 90 GSX a few months ago and have been slowly fixing all the problems... it didnt have a BISS screw when i got it so i got one of those and then the ISC was unplugged and the harness was cut so i fixed that, but after connecting the ISC and rewiring the wires so i could have a throttle stop it wont idle at all... probably a reason for that the harness was all cut up?

anyways it misses like crazy at idle and it'll idle great sometimes, but other times itll just fluctuate like crazy in 2 different modes... 1000-1500rpm and 500-1000 rpm... the second mode itll fluctuate twice then die... then sometimes itll die altogether like when i come off the freeway or after any kind of sustained speed...

I tried 2 different ics's and went through the Vfaq and both ISC's check out fine...

this leads me to beelive that perhaps i missed some kind of possibility that neither the throttle stop or ISC are adjusted properly..

any other ideas? take into consideration that this is a 90 model so it doesnt have a TPS...just the throttle stop and ISC..

thanks in advance... -Matt

 

[huafist]

Pressurize the intake and check for leaks. Run a compression check. All the normal stuff.

 

[oddrob]

90's should have a TPS as well, if you don not, that could be the problem. Otherwise it might be a vac, or air leak in the system. CHeck all your hoses, and I/C piping.

 

[Below Ambient]

well it stops dying when i turn on the AC... ill do an intake leak down in a few days.. i want to see if anyone else has had this problem...

 

[steve]

take into consideration that this is a 90 model so it doesnt have a TPS...just the throttle stop and ISC..

Of course '90s have a TPS. Are you sure yours is missing? Did the PO hack that off too?

Steve

 

[Below Ambient]

why is hte intake so different from my buddies 92? it seems like its missing something...

 

[steve]

Who knows what's been done to your car. A picture would help.

Steve