Tire-Kicking GVR4s Again [HELP]

I know, I’m the proverbial tire-kicker. But I’ve run across another GVR4 that has me really interested. It’s a '91 with 107k on it, was a 1 owner car w/ all documentation (service etc) until about 7 months ago when the current owner got it, and parked it. Runs, but won’t idle well. What are first easy/obvious things I should look at for the idle problem?



i think you pretty much have to, to make everything come full circle with me and the vette


could be a vacuum leak, intercooler pipe fell off, or perhaps your mother is feeding again and the air in the vicinity of the intake is within the grasp of her gravitational pull. thus starving the engine of oxygen.

I know this is sarcasm but a charge pipe off won’t effect idle unless there is a sensor before where it came off at

So, it actually high-idles, not rough idle. It hangs around 2.5-3k. I talked to a buddy of mine w/ a GVR4 and he said it’s almost certainly an IAC. However, the IAC can fry the e-prom in the ECU. So it could be a really, really cheap fix, or a moderately cheap fix. Made an offer and the guy is calling me tonight.


Why would a bad ISC fry an ECU?

At worst, you need an ISC, 20 bucks. Easy to test with a OHM meter. Measure resistance between 1-2, 2-3, 4-5, 5-6. All should be (I think) something like ~30.

350z, DSM’s have a MAF, so any charge pipe leaking/off is a very big issue.

I’ve never heard of that situation.

Idle issues are very common. I know this says surge but a lot of it is caused by the same stuff:



wat… karmen vortex! boost leaks would throw you off but i dont see how a major one can just “come”

iac or vacuuuuuum line leak.

you can use the biss screw to adjust the idle if you cant find anything wrong
also you can use the butterfly on the idle switch side but then ud have to adjust the tps for the right ohms as well


try running an open venting BOV on a DSM and tell me that a blown out charge pipe won’t affect anything. :rofl:



I run 2!


stfu DSM noob.

oh SNAP. my newbnesss ownz me.

I want a gvr4 : ( its like a mini evo

I vent the bov to atmosphere… but converted to a 3" gm maf thats a blow thorugh (after the bov)

with the stock style maf, a boost leak will cause issues.

:nono: Seriously TJ, you need to let this DSM fantasy go.

Too late my friend, struck a deal at $1400.

So, how do I begin my DSM friends? Are IAC/ISC whatever it’s called on a DSM available through typical parts stores still?



your new bible. post pics i want to see this thing

I think santa cruz is too far for me to drive out. pm me if you wish.

Pics ripped-off from his CL post:



And the next (scary) question, what would a reasonable offer be for these (prices below are asking-price):

4 Fic 550cc injectors- new orings- less than 2k miles $100

Aem fuel pressure regulator- new $100

Hks VPC WITH HKS 550 CHIP AND GGC for 1G DSM in good working condition- complete system with sensors and harness. $300

EVO III 16g like new, no shaft play, DSM GT high flow manifold tapped for EGT, EVO III o2 housing- less than 2k miles - $450

It sounds like I’d need late-model cams and a FMIC to get close to 300hp w/ these parts?



To answer your question.

And another “good deal or not” question: http://www.galantvr4.org/ubbthreads/showflat.php?Board=UBB1&Number=680851&page=0&fpart=1