fuel problem??

[JesseH]

ok, so heres the deal. This is a semi build that im just now getting going. Everything is together and it starts up fine although Im having some weird problems.

My biggest concern is it runs pig rich for the most part either 10:1 or off the chart on the AEM, then at other points it will start to lean out. Now keep in mind that this is not driving it, just Idle and moving back and forth a few feet. I noticed one thing was I had a NA FPR installed and didnt realize it at first (guy who I got it from ssaid it was off a turbo) Tonight I went and picked up a turbo FPR from a local guy, installed it and now it just starts and dies. I know its not the vaccum line, its right off the manifold, the fuel pump is almost new (walbro), along with the 12v fuel mod that I used on old motor. Is it possible that this FPR is bad? or is there anything else I should be looking for?

Oh, and this is a 87 GTE auto also has a FFIM and Q45 if that helps with the topic.

 

[IwantMKIII]

2 things stand out here....

running 'pig rich' even out of a WB range

12V feul mod with a walbro

what could these two things possibly be telling you

 

[JesseH]

2 things stand out here....

running 'pig rich' even out of a WB range

12V feul mod with a walbro

what could these two things possibly be telling you

yea, I figured it would run a bit rich, although I ran this on my old NA motor and it wasnt running that rich

 

[IwantMKIII]

yea, I figured it would run a bit rich, although I ran this on my old NA motor and it wasnt running that rich

maybe so but if im not mistaken the injectors are larger causing excessive feul and probably flooding the cylanders


check your feul pressure

 

[JesseH]

maybe so but if im not mistaken the injectors are larger causing excessive feul and probably flooding the cylanders


check your feul pressure

that might be possible, but the reason why I dont think that has much to do with it is because at idle it will change...for the first miniute or so it will sit around 12:1 then start getting rich without me doing a thing, and now that Ive put this other FPR on there it just dies after about 5sec. I wish I had the cash right now to get an aeromotive and be done with it.

 

[jdub]

Do you have the "J" tube on the return installed and is it drilled out?
(You REALLY should be running an AFPR and pressure gauge with this)

Do you have an ISCV installed for idle control?

 

[JesseH]

Do you have the "J" tube on the return installed and is it drilled out?
(You REALLY should be running an AFPR and pressure gauge with this)

Do you have an ISCV installed for idle control?

I dont have a J-tube on there at all, there is a block off plate on it.

And I do have the stock ISC on the FFIM

 

[jdub]

Is the ISC working and does it have a check valve (like stock) under it?

Need some more details on your set-up...Stock AFM? Stock TPS or re-wired Nissan? Any ECU codes?

 

[JesseH]

Is the ISC working and does it have a check valve (like stock) under it?

Need some more details on your set-up...Stock AFM? Stock TPS or re-wired Nissan? Any ECU codes?

stock AFM right now, ISC for sure works (stock supra one) The TPS is the Rewired Nissan, Only throwing a 32 for the HAC sensor but since this was a NA there isn't one on there right now (about to pick one up soon).

I think I might have found a pretty big problem, I touched my O2 senor wires and they sparked, appears that one of the wires is all chewed up causing it to give a bad reading.

 

[jdub]

Might want to check the wiring to the AFM and bench test it as well.

Also check all your IC piping for leaks, cracked connectors, etc.