Strange starting issue

[drifterdude]

Hi,

Let me start off by saying that I have done a lot of searching, and i came up with some similiar problems that other people's had, but none of there fixes worked out for my car, and things seem to be getting progressively worse.

I have a s13 blacktop sr in my s14, and prior to doing a turbo upgrade the motor was running strong as hell, no starting problems, idle problem, nothing, the motor was perfect. Then i decided to upgrade the motor by adding a gt2871r .64 trim, sard 850cc injectors, z32 mafs, z32 filter, enthalpy tuned ecu, walbro pump, and nismo adjustable fpr.

After getting the motor ready to run, i turn on the car and everything seems fine, except slightly higher idle, but i go to rev up the motor to around 4k and let off and the rpm's will drop and the motor dies and this happens every single time i rev up and let off. So i checked all my vacuum lines, checked fuel pump, and injectors and they all work. So i go to change my spark plugs, then go to fire up the car, and now it holds idle but about 10secs or so of good idling the car dies again. So i unplug my MAFS and fire the car up, and the car stays on, but the instant i plug the sensor back the car dies. So i thought it was a bad mafs. I go to start the car again, but now the car wont start at all.

Also timing should be spot on since i have not toyed around with the timing. Ive changed plugs, checked injectors, mafs was replaced with a working one, full tank of gas, etc...

If anyone can help me figure out why my car wont start now, i would appreciate any and all input.

Thanks in Advance.

[Mathetai]

Does it die like this after its warm... Check your A/F ratio

[drifterdude]

Yes, the car still dies after its warmed up, i didnt mention that when i had started the car the first time i let i warm up, and took it for a spin but everytime i disengaged the clutch the motor died.

How do i go about check my A/F ratio?

[yokotavia]

sounds like you have a really bad boost leak, check all your couplers to your intercooler, intake, and any other random hoses that hold pressure for boost.

[drifterdude]

No, its not boost leak everything is tightened, ive had boost leak before, but it was nothing like this.

Thanks

[MA JasonG]

Sounds like you might possibly have a boost leak. Have you tried testing? not just touching couplers to be sure they are tight but actually charging the system. Whats your fuel pressure btw? be sure to check this with the vacuum line on the regulator off.

[drifterdude]

ok ill give that a try in the morning, i should be able to do that by just disconnecting that vac line on the fpr, and priming the fuel right?

[tt99ol]

is the tune for a z32 maf? or maybe wiring is wrong, check it

[MA JasonG]

ok ill give that a try in the morning, i should be able to do that by just disconnecting that vac line on the fpr, and priming the fuel right?

correct....msglnth

[drifterdude]

Thats what i was wondering, ill probably get around to rewiring the stock mafs and see if the car will start, ive tried contacting enthalpy since they tuned it for me, but have not heard from them yet, i know there busy but hopefully ill get a reply.

[deesz]

is the tune for a z32 maf? or maybe wiring is wrong, check it


i agree sounds like a maf problem...

[MA JasonG]

Thats what i was wondering, ill probably get around to rewiring the stock mafs and see if the car will start, ive tried contacting enthalpy since they tuned it for me, but after 3 or 4 emails i have yet to get a reply. I know there busy, but a simple reply would be nice.

Yeah, he's kind of a hard guy to get a hold of. If you sent in your ecu and told him of your mods and having the z32 maf, I doubt its the tune. I would hold off rewiring your maf for now. continue using the z32 maf. See if you can, test the maf on a friends car thats running a z32 maf already. I doubt that's the problem though.

[drifterdude]

Yea ill try putting my mafs on my friends car and see if it works. thanks for the advice anything will help right now.

So if the fpr was too high then the car would run rich and shut off probably?

[MA JasonG]

Well I saw that you added an adjustable FPR and I've known previous people doing that and not setting it, causing flooding etc and the car dying out. Just trying to eliminate all possibilities that I can think of at 3am in the morning. hahaha. But if I can think of any other possible problems I'll let you know.

[drifterdude]

Well i checked my fuel pressure, and thats right at 43psi, and i beleive that its good at 43.

The reason my car didnt start after i pulled the mafs is because i think i flooded the motor. But thats not the issue anymore, and i was able to get the car started this morning after burning away the excess fuel.

But the car seems to be slightly better, i am able to fire up the car and the car will stay on but when i rev it will die or if i let it sit idling for 5min or so it will die but only if its between 500-1500 rpm, anything above and teh car sounds fine and doesnt feel like its goign to die.

I guess the next step is to charge the pipes, but my question is how exactly is the best way to go about doing that?

So, its not injectors, spark plugs, dont think its the tune anymore, not the maf, wiring is good, so tonight i will test my pipes but some pointers on how i might go about doing this could definately help.

I was thinking of just putting soapy water are my welds and around the couplers and firing up the car to see if i have leaks, but i couldnt imagine a small leak causing my car to act the way it does?

Thanks

[drifterdude]

bump.......msglngth

[MA JasonG]

does your car stay at a constant idle? and if so what rpm?

[drifterdude]

I think i found the problem, and im really embarrased to say that it is a boost leak. But its coming out of one of the welds where i had welded the bov flange, but i had trouble welding the mild steel with some galvanized steel flange. The welds on that turned out kinda crappy. Is a couple of pin sized holes enough of a leakage to do what its doing?

Thanks for the input, i think im going to just chop the pipe at the welds and throw in a coupler.

[zaneithan]

I think i found the problem, and im really embarrased to say that it is a boost leak. But its coming out of one of the welds where i had welded the bov flange, but i had trouble welding the mild steel with some galvanized steel flange. The welds on that turned out kinda crappy. Is a couple of pin sized holes enough of a leakage to do what its doing?

Thanks for the input, i think im going to just chop the pipe at the welds and throw in a coupler.

even if its not all of the problem, its a portion of it, id get that fixed asap and go from there