Intermittent stall/power loss OFF boost

[Spoolin92GSX]

So I have searched, extensively, and haven't been able to find this same problem resolved.. I have a 92 GSX with basic bolt-ons (sig list is current) and I'm having issues with an intermittent stalling/power loss. First off, it seems to only do it when the engine is fully warmed (FIAV inactive, right?) and worse when it's cooler outside. When at a resting idle, it jumps a little between 500-800rpms and vacuum is only around 10in/hg. Then I start off, it hesitates a little until 3k rpms and then my boost goes from 0psi straight to 12psi (full boost). Then usually after that it's fine. Also, if this condition starts while I'm moving, the car will stall when I press the clutch while moving, and starts right back up instantly. Really appreciate any help or suggestions!

BTW a boost leak test was performed in the last month and all was good, but I figure I'll check that out again. Timing and belt was just done not too long ago. I am running catless, but it seems like I'm running PIG rich by the exhaust smell.

I'll try to get a video of it misbehaving if that might help.

 

[91awd26]

Are you recirculating your bov? Sounds a lot like mine acted when I first got it and the P.O. had the recirc. tube off.

 

[Spoolin92GSX]

Yeah, sorry I should have added that too. BOV is recirc'd and connected properly.

Here's another thought.. The P.O. smogged the car for me, and switched the catless DP for stock catted and back again. Would unplugging the battery to reset the ECM do anything?

 

[Spoolin92GSX]

Okay, boost leak test done.. Throttle body shaft seals and BISS o-ring are shot - could this be my problem?

 

[SpeedMetal]

Okay, boost leak test done.. Throttle body shaft seals and BISS o-ring are shot - could this be my problem?

It be could, but would just run rich. Though, not rich enough to stumble as bad as you make it sound. Try checking the injector clips for brittleness or broke wires. Happened to me on my old 90'.

 

[Spoolin92GSX]

Hmm, I'll have to check that too.. I noticed this morning (cold start) that it almost felt like it went on 2 cylinders for a couple seconds.. Might have to check ignition too

 

[91awd26]

Clips on the injectors are a very good thing to check for. I have had many dsm's where people decided they didn't need to have those clips on there anymore. Mine were missing and it would randomly cause my car to act up and skip. Also how you said the BISS o-ring is shot, I have had the BISS screw blow out completely on a couple different cars and each time it caused very rough performance and stalling so that also may be your issue and would be a good place to start. Fix what you know is wrong and go from there.

 

[Spoolin92GSX]

Clips on the injectors are a very good thing to check for. I have had many dsm's where people decided they didn't need to have those clips on there anymore. Mine were missing and it would randomly cause my car to act up and skip. Also how you said the BISS o-ring is shot, I have had the BISS screw blow out completely on a couple different cars and each time it caused very rough performance and stalling so that also may be your issue and would be a good place to start. Fix what you know is wrong and go from there.

Wow that's got me suspecting the clips even more now, mine skips randomly at idle too. Thank you for the input!

 

[bryanwheat]

I'd suspect something compression or timing related it the timing truly is only at 10in/hg

 

[mb3000]

Wouldn't hurt to clean/test the ISC

 

[greene3543]

Mine did something similar a few months back, fuel pressure and timing was my issue, may wanna check that while you're in there.

 

[brownfinger]

I'm thinking fuel pump or ECU. The compression can be pretty much shot, and it should still run OK with a stock set-up. My DD is running a newer ECU, the old ECU used to cause all kinds of ghost problems. Until the ECU blew-up. My previous DD ran rich all of the time. I checked and replaced all kinds of stuff, but it continued to run with all the fuel trims maxed-out. The fuel pump was weak.

Do you have a data-logger?

 

[Spoolin92GSX]

Nope, no logging capabilities as of yet.. Once I get these kinks smoothed out and get my evo III set-up I'll be getting DSMLink.. Next time I have time I'm going to pull the ECU and check the caps and whatnot. Since I just bought the car and not sure how it's been treated, or how knowledgable the owners/mechanics were, I'm going to go through the ignition system this week too.