running too rich. help!!!

[supraman16]

Frustrated as hell. Just installed my venom 550 injectors to correct my lean
condition with the lexus afm, also installed walbro 255 fuel pump. Vehicle ran strong with no problems after 4th test run vehicle started running real rich, check ic pipes and intake for leaks, none present. I have a adjustible fuel pressure regulator not installed as yet. Will this help my running rich condition? Current set up is 550 injectors, walbro 255 fuel pump, apexi cold air, 3 1/2 inch down pipe through exhaust no cats, manual boost controller
set at 14.0 psi, ngk wires uridium plugs, metal head gasket arp head studs,
hks blow off valve, stock ct-26 rebuild. Anyone with ideas to tune this properly. I'm THE SAME CRAZY DUDE THAT RAN THIS SET UP WITHOUT 550'S
AND RAN 13.9 AT COMMERCE. ANY ADVICE WOULD BE APPRECIATED.

 

[suprahero]

I have basically the same setup as you. I run rich all the time. My car pops when I shift gears while putt putting around. I have had it tuned and it runs perfect at WOT, but it's rich the rest of the time. I was told by the tunere that I could remove fuel with my safcII at lower rpm's and it may help a little bit, but basically I was told it was going to run a little rich. If you figure it out let me know.

I have my aeromotive fpr installed, 550's, 2555 fp, lexus afm....................lol

 

[Doward]

Drop the fuel pressure a little.

 

[robbo185]

did you drill out or bypass the j-tube?

 

[Nick M]

If he ran fine the first four times, then it went to hell, something happened right there.

Unless he wasn't running as well as he thought. But I don't have the crystball handy.

The more you drive your car at WOT, the more the ECU will go with fuel trim.

 

[jdub]

I assume you are measuring AFR with a wideband O2. How rich and at what throttle settings? AFR at ide, normal cruise, and high rpm would be helpful. Also, check for ECU codes...if you have any, they will need to be solved before start adjusting your fuel pressure.

Install the AFPR and start with the fuel pressure at the low side of spec with the vac line removed. And As Robbo185 suggested, removing the "J" tube or drilling it out will remove the restriction going to the tank and help to properly adjust the AFPR.

 

[supraman16]

When I get back to the shop monday I'm gonna put it on the lift and
recheck all the piping. Going to install the the regulator and set it at 28 psi
for fuel. I'm gonna kill all ecu memory and try it again. I will post the results
to help anyone else.

 

[jdub]

When I get back to the shop monday I'm gonna put it on the lift and
recheck all the piping. Going to install the the regulator and set it at 28 psi
for fuel. I'm gonna kill all ecu memory and try it again. I will post the results
to help anyone else.

Min fuel pressure with the vac line removed is 33 psi....
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_073.html

 

[suprahero]

HiJack alert!!!!! If my car is running rich and my afpr is set at 38 psi, would lowering the fp a little help it lean out at idle? It runs great at wot, but when you're just driving normal, it runs rich. Thanks.

Sorry for the hijack Supraman..................lol

 

[jdub]

It helped my AFR. When I installed the Walbro, my AFR went rich (to 13.5) at cruise. I have the same set-up...550's, Lex, AFPR, no "J" tube...the fuel pump replacement was the only change. Looked at my fuel pressure and it had gone to 45 psi (I didn't have any codes). I dropped it to 35 psi (vac line removed) and reset the ECU. Car's been running at 14.7 AFR since.

 

[suprahero]

Gracias mi amigo.............lol


That's greek for thanks for the answer..................

 

[supraman16]

Finally fixed. I installed the adjustable fuel pressure regulator set the psi at 28
psi, the car is fantastic!!!! Idles smooth and runs very strong at 14psi. I'm going to bump the boost to 16 psi and adjust the fuel pressure as needed.
I might not need an afc.

 

[suprahero]

Glad to hear. I thought that 33psi was the lowest your suppose to go. I read it somewhere, it may have been on this thread. You might want to check into it before something goes..........BANG!!!!!!!!...........lol

 

[jdub]

Finally fixed. I installed the adjustable fuel pressure regulator set the psi at 28
psi, the car is fantastic!!!! Idles smooth and runs very strong at 14psi. I'm going to bump the boost to 16 psi and adjust the fuel pressure as needed.
I might not need an afc.

What are your AFR's?

 

[jetjock]

Check sig

He never told us throughout any of this. Nor did he confirm your assumption that he was employing a wideband. Appears to be a case of pure butt dynoing to me. No pun intended but stay tuned for more news on this one.

 

[suprahero]

Are you referring to the low post count? Hopefully so and not the Atlanta part. I don't think you would condemn someone for where they live. Post count, yes, location, no.................lol

 

[suprahero]

JJ, while you're on here. Would it change my a/f alot if I lowered my fp to about 35 instead of 38 that it is now? My a/f's at 2000rpm are between 13.5 and 14. At wot they go between 11.2-11.8 at 5500 rpm. It just idles real rich. I can also take it out with my safcII if that is better for my car. Just thought I would ask.

Sorry for the hijack, but you said yours was fixed................lol

 

[jetjock]

I was referring to jdub's sig while using a play on words he should understand.

I thought the purpose of the safc was to adjust fuel by scaling the airflow signal? Changing fuel pressure is useless up to a point. All that'll happen is the ECU will increase or decrease injection duration to keep the exhaust stream at stoich. As long as you're in closed loop it'll do this. If it can't do that, if the system reaches a point (called the adaptive limit) where no further correction can take place then yeah, mixture will be effected. In fact it seems you're already beyond the adaptive limit. Not an optimum setup.

Turn the safc off and set fuel pressure so as to get back to stoich at idle and cruise. Then set the airflow controller up from there.

Btw, I like Atlanta. I don't care where the guy is from as long as he doesn't bust out the windows and weld the doors shut

 

[jdub]

Check sig

He never told us throughout any of this. Nor did he confirm your assumption that he was employing a wideband. Appears to be a case of pure butt dynoing to me. No pun intended but stay tuned for more news on this one.

LOL :naughty:

I'm trying to lead the horse to water....we seen the result of detonation a couple of time recently huh. That fuel pressure seems a little low using 550's with a Lex.

Suprahero - JJ is right. There is only a limited amount you can do with adjusting the FRP. It's a hit and miss thing (took me several tries w/ ECU resets), but you do want a base at stoich before you tune with a S-AFC.

 

[supraman16]

Not sure if I want to mess with it anymore. Everything is perfect right now.
I do plan to get a safc we get good deals from Summitt from the shop.
But until i turn the boost up some more I'm just going to keep an eye
on everything day by day.