Not clueless, but would like experienced opinions

[Rekadae]

Boy oh boy, I don't quite know where to start on this one.

So I have a 97 GST, which has a build profile before somebody asks me for specs and whatnot in order to properly help me out.

Quick rundown of what I've been doing with it.

When I first got the car I did an oil change, got an ecu that had been adjusted for the 650cc injectors that came with the car to attempt to get rid of the supposed 'fuel cut', put it in with the injectors, turns out it wasn't fuel cut. Took out injectors in order to put spacers in so that I could properly tighten down the rail, buttoned everything back up, and now when I go to start the car it fires up sounds fine for a second sputters down and dies. Thinking atm it could be due to a vacuum leak somewhere, I have done somewhat of a boost leak test not at high psi or anything yet.

So basically what I'm asking is what could possibly be causing the stuttering when I go to give it gas other than fuel cut/boost leak?

And, what could possibly be causing my car to fall on its face and die when I start it? Mind you I have brand new plugs in it.

 

[linksys42]

Without that blow off valve being recirculated. It is causing a massive vacuum leak at idle. Unmetered air is bypassing the MAF. You can verify this by having somebody start the car up and looking down the outlet of the blow off valve and see the valve plate opening and allowing unmetered air to get in causing a giant vacuum leak. I know that you're planning to fix it by installing ecmlink and going the speed density but I think this is your problem right now. So just to clarify you were still having this issue before you swapped in the new ECU and injectors right?

 

[Vegas Smith]

Can you verify what the base fuel pressure is as well?

 

[Rekadae]

Yeah, same issues before this new ecu and injectors. Although I don't think much air is getting out of the BoV at idle... Doesn't make much sense if it was opening at idle and holding any boost at all in other scenarios, if it was able to open at idle and leak it would just shit the bed 24/7.

Also yes, my base fuel pressure is fine, checked it prior to everything with my fpr

 

[linksys42]

Doesn't make much sense if it was opening at idle and holding any boost at all in other scenarios, if it was able to open at idle and leak it would just sh** the bed 24/7.fpr

At idle with negative vacuum on the diaphragm in the blow off valve will pull the valve open via the vacuum line from the intake manifold to the blow off valve. When the blow off valve sees positive pressure (boost) from intake manifold during boost it assist in holding the valve completely shut so boost doesn't bleed off or leak. It's all dependent on what the blow off valve sees at vacuum / boost during operation of engine. Stalling and driveability issues are a very common problem with venting a blow off valve. Your blow off valve a greddy is actually tunable via the adjustment threaded rod and nut on the top of the bov you can do a search to find out how to properly adjust it.

http://www.dsmtuners.com/threads/venting-your-bov-to-the-atmosphere.113858/

 

[Rekadae]

At idle with negative vacuum on the diaphragm in the blow off valve will pull the valve open via the vacuum line from the intake manifold to the blow off valve. When the blow off valve sees positive pressure (boost) from intake manifold during boost it assist in holding the valve completely shut so boost doesn't bleed off or leak. It's all dependent on what the blow off valve sees at vacuum / boost during operation of engine. Stalling and driveability issues are a very common problem with venting a blow off valve. Your blow off valve a greddy is actually tunable via the adjustment threaded rod and nut on the top of the bov you can do a search to find out how to properly adjust it.

http://www.dsmtuners.com/threads/venting-your-bov-to-the-atmosphere.113858/

Yeah that is adjusted and whatnot which is what I'm saying. The cause is 99.99% not the bov from what I've gathered.

 

[pauleyman]

Yeah, same issues before this new ecu and injectors. Although I don't think much air is getting out of the BoV at idle... Doesn't make much sense if it was opening at idle and holding any boost at all in other scenarios, if it was able to open at idle and leak it would just sh** the bed 24/7.

Also yes, my base fuel pressure is fine, checked it prior to everything with my fpr

Blowoff valve, any brand, will be open at full vacuum idle. That's how they work. The reason it doesn't cause a problem stick is all of the piping stock is a big loop AFTER the maf. By venting to atmosphere that loop is open.

 

[Rekadae]

Blowoff valve, any brand, will be open at full vacuum idle. That's how they work. The reason it doesn't cause a problem stick is all of the piping stock is a big loop AFTER the maf. By venting to atmosphere that loop is open.

Yeah but again, that wouldn't be the issue because the car was running and driving prior to me doing this. It may be causing 'an' issue but that is not -the- issue I'm currently trying to resolve.

 

[pauleyman]

Yeah but again, that wouldn't be the issue because the car was running and driving prior to me doing this. It may be causing 'an' issue but that is not -the- issue I'm currently trying to resolve.

Point taken. I'd still suspect anything you just touched. Spark plug gap. wires etc. Combine a marginal problem with the one you already know about (bov) and yes the BOV could be contributing. I would fix it either way.

 

[linksys42]

because the car was running and driving prior to me doing this.

What is ("this"). What did you do that the problem showed up afterwards? Because it wasn't clear to me really in your post's.

 

[Rekadae]

Problem atm is the car is starting up, and then falling on it's face and dying after a few seconds. Checking a bunch of shit after I get my fuel rail spacers and the oem fuel rail bolts. And yeah I would fix my bov as well though unfortunately I'm having quite a tough time finding any sort of hose that would work with the aggressive angle the bov needs to recirculate, and without being able to drive it atm I can't quite just buy random radiator hose and 'hope' yknow?

List of things I'm going to be checking after I fix any potential for a gas leak from injectors

1. PT on Intake Manifold
2. Plug Wires
3. Coil Packs
4. Spark in general

Also, my plugs are brand new and gapped to .28

 

[linksys42]

Problem atm is the car is starting up, and then falling on it's face and dying after a few seconds. Checking a bunch of sh** after I get my fuel rail spacers and the oem fuel rail bolts. And yeah I would fix my bov as well though unfortunately I'm having quite a tough time finding any sort of hose that would work with the aggressive angle the bov needs to recirculate, and without being able to drive it atm I can't quite just buy random radiator hose and 'hope' yknow?

List of things I'm going to be checking after I fix any potential for a gas leak from injectors

1. PT on Intake Manifold
2. Plug Wires
3. Coil Packs
4. Spark in general

Also, my plugs are brand new and gapped to .28

Did this just start randomly? or after you worked on something on the car? And just to give you a heads up the outlet the horn on that greddy blow off valve. You're not going to be able to attach a hose to it to recirculate it. (A recirculate hose won't slide over that horn). They sell a separate attachment for recirculating that blow-off valve that's a straight pipe for that type bov.
https://www.amazon.com/Torque-Solution-Recirculation-Adapter-Aluminum/dp/B006G36YAU

 

[pauleyman]

Problem atm is the car is starting up, and then falling on it's face and dying after a few seconds. Checking a bunch of sh** after I get my fuel rail spacers and the oem fuel rail bolts. And yeah I would fix my bov as well though unfortunately I'm having quite a tough time finding any sort of hose that would work with the aggressive angle the bov needs to recirculate, and without being able to drive it atm I can't quite just buy random radiator hose and 'hope' yknow?

List of things I'm going to be checking after I fix any potential for a gas leak from injectors

1. PT on Intake Manifold
2. Plug Wires
3. Coil Packs
4. Spark in general

Also, my plugs are brand new and gapped to .28

check the plugs anyway. I've accidently damaged one on install and didn't realize it until they were in. It was immediately evident.

 

[linksys42]

I just reread through this post carefully. So you're saying this problem started after you did a boost leak test? Is that all you did that day is a boost leak test or did you work on other parts of the engine.

 

[Rekadae]

I just reread through this post carefully. So you're saying this problem started after you did a boost leak test? Is that all you did that day is a boost leak test or did you work on other parts of the engine.

Boost leak test after putting a new gasket and gasket maker on the throttle body to intercooler piping, CAS was resealed with gasket maker to prevent oil leaking, New intake filter, new spark plugs, BOV was filed down to be flush since previous owner butchered it in a vice new gasket and gasket maker on that as well. That's it though.

 

[PlanZero]

Please tell me your maf is plugged in properly. That little rubber gasket gets in the way sometimes.
Also, try the bendable radiator hose for the bov (with the coiled wire running through it) pain to work with but holds up great. I've used the spa hose before but it cracked after a few months.

So supposedly this car has a 6bolt block/7bolt head with 1k on the rebuild? Have you verified any of this or do you at least know the PO enough to believe him?
Once upon a time it was believed the 1g 6 bolt bottom end was an upgrade to the supposedly crankwalk prone 95-97 7 bolt. That's pretty much been dismissed at this point (if anything the revised 98-99 is tits) for various reasons, but people still lie about a 6bolt block as a selling point not thinking a potential buyer will check. All I'm saying is make sure everything you were told is true.

 

[Rekadae]

Yeah, didn't even know there was bendable radiator hose! I'll for sure give that a shot, and the MAF is plugged in correctly, but I'll double check still waiting on my fuel stuff so not much I can do until then. Yeah the PO had lots of documentation of it and whatnot and I spoke with the shop that did it, just was a skeptic moment that I mentioned it for earlier bracing for the worst yknow? Not going to name any names but I know several shops who have openly stated in complete seriousness that for the right amount of $ they would fake paperwork

 

[linksys42]

I would Check all electrical connections to devices you were working on that day, throttle body – TPS, ISC, I would also make sure that the wire clip for the TPS connector is installed. I would test the TPS via voltmeter or Data Logger. As it's been said already I would test the cam angle sensor and elec connection. Double check the MAF electrical connection and operation via Data Logger. Also I would re-do boost leak test, testing it to at least 15 psi and using soap and water to track down leaks. Good luck.

 

[Rekadae]

Update on this thread many months later. I eventually went back and checked the one thing I let a buddy help me with my CAS had a leak and we redid the gasket on it. Of course he flipped the piece on the inside 180. Swore by it he put it in the way it came out, guess not.


Discovered this a month or two after posting this, wasted a bunch of money on electrical as well, won’t make that mistake again.

 

[spyderdrifter]

Good to hear you found the problem, and t turned out to be simple. Sorry for the drop off in help back then, job crap f@&ked me over and I forgot it all.

 

[Rekadae]

All good man, this car is getting completely revamped staying fwd now has a Quaife Lsd and made 330whp. Going to put a different motor and harness in so my burning oil problem can be investigated and I will no longer have a rats nest.

Goal is to track the car at GridLife Midwest this upcoming season.

I’ve learned a substantial amount since the last time I posted here to say the least

 

[spyderdrifter]

Nice. I'm currently building a new engine for my talon. Short block is done, eagle rods, wiesco pistons, & BSE.