Intermittent miss up to 2k and idle when warm NA-T

[pwpanas]

Originally Posted by Travis89Turbo

Update!

I bought a new Mac tools pro fuel pressure test kit and it had a banjo bolt adapter that I hooked into the top of the fuel filter...

Results- with Vac line disconnected and plugged 51psi. Factory spec 38-44

With vac line hooked up 42psi. Factory spec 28-34

1500 rpm 55psi with vac line hooked up. That is out of factory specs so I will be replacing it.

I apologize for not adding the info about the stock distr cap. I reinstalled the original with no change. Although I did have to change plug wires back to OEM as well. So I put the 4 runner stuff back on and doubled checked that the timing is at 10btdc.

Is it possible that the added pressure from boost could damage the factory fuel regulator?? Should I stick with OEM or go to an aftermarket in your opinion.

My BOV is an HKS SSQ that I bought a recirculation nipple for so it has been blowing back into the intake post MAF, pre turbo!

Regarding the FPR, I'd try with one from an Mkiv TT if it's a different part number and if it fits. You could even try a used one (yours is the first I've heard of one that has problems). Just a thought - do you think your fuel return line could be blocked/kinked/crimped in any way - that would raise fuel pressure regardless of how well your FPR works. You could always go to an aftermarket FPR (a lot more expensive, especially after the adapters, braided hose, etc.) if a different oem fpr doesn't do the trick.

To bad you don't have a fuel controller (eg. A'PEXi AFC) - you could just dial down the fuel at idle based on the higher fuel pressure, then the additional fuel would be available under boost. Capiche?

[Travis89Turbo]

Originally Posted by pwpanas

I hope you don't mind me tooting my own horn a bit, but I did suggest you should check the fuel pressure before replacing the fuel pump.

Regarding the FPR, I'd try with one from an Mkiv TT if it's a different part number and if it fits. You could even try a used one (yours is the first I've heard of one that has problems). Just a thought - do you think your fuel return line could be blocked/kinked/crimped in any way - that would raise fuel pressure regardless of how well your FPR works. You could always go to an aftermarket FPR (a lot more expensive, especially after the adapters, braided hose, etc.) if a different oem fpr doesn't do the trick.

To bad you don't have a fuel controller (eg. A'PEXi AFC) - you could just dial down the fuel at idle based on the higher fuel pressure, then the additional fuel would be available under boost. Capiche?

I actually have a friend sellin a AEM ems v2 for the ge for $1000 with COP setup and a gm 3 bar map. I've been consodering but I have spent a lot of money this year! Buying a 32ft boat didn't help either.

Like you I have never had a regulator go out on me and the Walbro 255 is cheap insurance. Not to mention was way cheaper then the fuel press. Kit I bought!

I was just lookin into the gte regulators from what I have read they are interchangeable. I will be ordering one in the next few minutes. Thanks for your help Phil!

I'll keep ya posted if this resolves my issue for good!

[Travis89Turbo]

Okay. I installed an aftermarket Aeromotive regulator with steel braided lines set within factory specs.

All seemed great yesterday afrs were where the should be around 14.7 so I parked it and then while driving to work this morning guess what came back! The lope in the idle.

Agghh. The CEL did come back on and I will be checking that at lunch time and will update that info. I have no idea what's goin on.


Is it possible my headgasket is seeping? Although I am not missing fluid.



I put some new fuel in it with some injector cleaner so time will tell of that helps at all.

[pwpanas]

Originally Posted by Travis89Turbo

Okay. I installed an aftermarket Aeromotive regulator with steel braided lines set within factory specs.

All seemed great yesterday afrs were where the should be around 14.7 so I parked it and then while driving to work this morning guess what came back! The lope in the idle.

Agghh. The CEL did come back on and I will be checking that at lunch time and will update that info. I have no idea what's goin on.


Is it possible my headgasket is seeping? Although I am not missing fluid.



I put some new fuel in it with some injector cleaner so time will tell of that helps at all.

Per my post above, have you checked for boost/vacuum leaks yet via pressurizing the intake yet?
One potential issue is a split vaccum (or charge air) hose that weakens with heat. A boost leak check will detect this (and an ordinary smoke test won't).

Here's another thought (while we're on the topic of split hoses):
http://autos.groups.yahoo.com/group/mkiv/message/230604

[Travis89Turbo]

Originally Posted by pwpanas

Per my post above, have you checked for boost/vacuum leaks yet via pressurizing the intake yet?
One potential issue is a split vaccum (or charge air) hose that weakens with heat. A boost leak check will detect this (and an ordinary smoke test won't).

Here's another thought (while we're on the topic of split hoses):
http://autos.groups.yahoo.com/group/mkiv/message/230604

I have not yet pressurized the system I will do that this evening after building an adapter.

I pulled the code ==== 25 lean condition?? Fuel pressure is within spec.

[Travis89Turbo]

I am starting to think possibly a bad MAF. I am running out of money fast throwing parts at it. Do you kno how to test the MAF on a ge??

Also at lunch today the check engine light went out on its own. At times my afr are perfect idling at 13.9 then all of a sudden just fall on its face down to 16-17. I unplugged the maf and it did not change the way it was missing???

I am also goin to ohm out the injectors this evening as well.

[pwpanas]

Originally Posted by Travis89Turbo

I am starting to think possibly a bad MAF. I am running out of money fast throwing parts at it. Do you kno how to test the MAF on a ge??

Also at lunch today the check engine light went out on its own. At times my afr are perfect idling at 13.9 then all of a sudden just fall on its face down to 16-17. I unplugged the maf and it did not change the way it was missing???

I am also goin to ohm out the injectors this evening as well.

The easiest way is to swap it out with another Supra. I agree this is a possibility. One of my Supra buddies did have a MAF go bad.

Do you have the TSRM? I know it's a few bucks, but it's money well-spent that will pay itself back over and over again. The MAF test procedure and thousands of other useful procedures are detailed in it.