So I am hoping someone can help me shed some light on this issue of mine. I recently got my 91 back on the road after an extensive rebuild to the front half of the car including the motor. I put BC stage 2 cams, a 57 trim ct26, Evo 8 560cc injectors, and a Lexus AFM housing for performance upgrades. I put in an AFM and drove the car around a bit and the gauge spikes to 10.2, but mostly stays between 8 and 9 air-to-fuel. It also hits fuel cut around 3500 rpm in any gear after third and fuel cuts at about 5000 rpm in second gear. The reason I mention that is because in first gear, I can run up to redline with out much incident. I am running the stock computer still with no safc. I am beginning to think I will need to go full standalone to be able to tune the fuel curve down. Does anyone have any thoughts?
Running rich as #@*&
- Thread starter ca91mkIII
- Start date
This is just a shot in the dark, but it seems like it would make sense in your case, and due to the fact that you've had your motor all apart:
Boost leak.
Boost leak.
You don't hit fuel cut in first because the load on the engine isn't there to make full boost for very long, hence why third and up is every time. I'm with supraguy, boost leak. What PSI are you trying to get to? I can run 16-18 PSI on my 57 trim and not hit fuel cut.
ca91mkIII;1981689 said:
Short pins TE1 and E1 in the diagnostic box with the KOEO. If you have a leak, you will get 3 flashes followed by 4 flashes. Or your cams are too much. I don't know anything about them. If you have a lot of overlap, you will not build "boost" on the gauge even though you are flowing a bunch of air.
Ive found lots of small leaks that never threw a code. I made an adapter, take off accordian hose and push 20 psi through the turbo inlet. You can cap off the 3000 pipe to just check all the piping....
Nick, if they dont throw a code does that mean they are probably not significant enough to really affect much?
Nick, if they dont throw a code does that mean they are probably not significant enough to really affect much?
If you have over boost fuel cut, you have seen the engine cut out for a moment and the MIL illuminates, then 34 is set. Sure, you can have an intake leak and never been in "boost". The car will be lean, not rich. I only wanted to answer how to look for a "boost leak". Although his symptoms in the OP indicate as such.
For an update and to see what you guys think... I tightened up all the t-bolt clamps this afternoon and dropped the fuel pressure and took the car out for a test drive. I drove roughly a mile with out really getting on the throttle with the afrs reading the normal 10.2. I came to a stop and then punched it and the car ran perfect and beautiful up to redline in all gears. Of course I was a little busy, so I didn't see what the afrs were. I then continued driving and punched it again and it is hitting fuel cut just as bad and running just as rich. I am guessing a coupling at either the turbo or the intake moves around when the motor is under full throttle, but I don't understand why I am still running super rich. The fuel pressure is roughly 38 psi with out the vacuum line being connected and with vacuum connected it drops to 21 psi. Any ideas on why its running rich still?
What is there to not understand? Have you done a boost leak test or did you just tighten all your clamps and call it good? Have you looked into the overlap of your cams suggestion? Hitting fuel cut at 6psi is not normal. If you dont want to put in the work to fix your issue just spend the few hundred and take it to a tuner that knows supras and be done with it.
Whoa, with the vacuum line connected you're losing 17 PSI of fuel? Mine goes from 40 disconnected to 32-33 connected.
Is your TPS set properly?
Is your TPS set properly?
7M4EVR - Since you want to be a douche, these cams from Brian Crower are plug and play cams designed specifically for the 7M-GTE motor. According to BC, one can even run the STOCK springs with these cams. They are .008" longer advertised duration and .019" longer duration at .050." With that being said, no I have not checked to see if the cams are a problem because they are so mild. The other reason I do not think cams could be a problem is because they are mechanical, so the car will always have the issue. It will never run strong until I play with the cams which I have not done. My brother drove it this afternoon and again it ran perfect and then he drove it again later on, and it ran like shit. So it has to be something that is variable. I tightened up the clamps first to see if that would make a difference because I have not checked them since I put the motor together. As of a few hours ago, a friend of my brother's did do a boost leak test using a fog machine designed for checking air leaks. That test yielded no leaks. And finally, I am willing to put the work into it, hence the reason I am still responding to my thread rather than making one post and never looking at it again. 7M4EVR, I am not trying to start an argument here, you just came off as a know it all.
Indigo - How would the TPS adjust vacuum at the AFPR? I have not checked the TPS yet, but it is still set to the factory chalk marks.
No unfortunately 10.2 afr is not a typo. I know ideal is 14.7, but my motor will not lean out any further then 10.2:1.
Indigo - How would the TPS adjust vacuum at the AFPR? I have not checked the TPS yet, but it is still set to the factory chalk marks.
No unfortunately 10.2 afr is not a typo. I know ideal is 14.7, but my motor will not lean out any further then 10.2:1.
well, timing is one thing. I've never seen an engine pull that much at idle. 10.2 is stupid rich, you need to check each piece of your efi system. when was the last time your injectors were flow tested?
I don't remember if you said it or not but name each of your mods. anything you've changed even as far down as rewiring something.
I don't remember if you said it or not but name each of your mods. anything you've changed even as far down as rewiring something.
The injectors are brand new from Rockauto as of June or July.
The mods to my motor are as follows: Brian Crower stage 2 cams with 264/264 degrees duration advertised and .336"/.336" lift compared to stock cams of 256/256 degrees duration advertised and .297"/.297" lift. Titanium springs and retainers. CP-Carrillo pistons with Eagle "H" beam connecting rods. 57 trim ct26 turbo, Driftmotion IC kit, Driftmotion upgraded oil pump, divorced downpipe, Evo 8 560cc pink top injectors, Tweakd Performance engine wiring harness, Lexus V8 afm housing with stock Supra afm, Spectre red air filter, ATI harmonic balancer, Innovate Motorsports afr with gauge, Aeromotive afpr with stainless steel flex fuel line. That is everything I can think of for the moment. I checked engine codes again today and all that is in there is code 51 which relates to the air conditioning system that isnt hooked up at the moment and the neutral safety switch which I have bypassed because of the heavier duty clutch.
The mods to my motor are as follows: Brian Crower stage 2 cams with 264/264 degrees duration advertised and .336"/.336" lift compared to stock cams of 256/256 degrees duration advertised and .297"/.297" lift. Titanium springs and retainers. CP-Carrillo pistons with Eagle "H" beam connecting rods. 57 trim ct26 turbo, Driftmotion IC kit, Driftmotion upgraded oil pump, divorced downpipe, Evo 8 560cc pink top injectors, Tweakd Performance engine wiring harness, Lexus V8 afm housing with stock Supra afm, Spectre red air filter, ATI harmonic balancer, Innovate Motorsports afr with gauge, Aeromotive afpr with stainless steel flex fuel line. That is everything I can think of for the moment. I checked engine codes again today and all that is in there is code 51 which relates to the air conditioning system that isnt hooked up at the moment and the neutral safety switch which I have bypassed because of the heavier duty clutch.
code 51 is also tps. its 3 things, idl contact is off on the tps, your foot is on the gas or the a/c button is pushed during the test.
recalibrate your tps.
recalibrate your tps.
Yes to the j-tube delete.
What do you mean by my foot is on the gas or the a/c button is pushed during the test? Are you meaning when I am checking the check engine light, the a/c button is depressed or my foot is pushing on the throttle?
Also a buddy of mine was mentioning that the afm itself needs to changed over to the Lexus V8 afm for the swap to work properly. Is that true or will that not change anything? I have been hearing it both ways now and since you said you are running the same swap with no problems, what do you have Indigo?
What do you mean by my foot is on the gas or the a/c button is pushed during the test? Are you meaning when I am checking the check engine light, the a/c button is depressed or my foot is pushing on the throttle?
Also a buddy of mine was mentioning that the afm itself needs to changed over to the Lexus V8 afm for the swap to work properly. Is that true or will that not change anything? I have been hearing it both ways now and since you said you are running the same swap with no problems, what do you have Indigo?
supra electronics with lexus afm.
yes, while you are checking the engine codes. I will find the cygnus and link it here.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=28
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=101
yes, while you are checking the engine codes. I will find the cygnus and link it here.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=28
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=101