Well with the car running good and the only issue being the boost creep issue I would like some imput on how to rid the car of this. Again I have a 57trim ct-26 and a recirculated ddp with 3" the rest of the way back.
Over the past few months I have been reading and trying to figure out how to get my car running good on the lex afm/550 combo. I think I have finally got most of the fine tuning figured out. The car no longer stalls, pulls hard, and drivibility is good. If anyone has questions on this I will do my best to help with the information I have learned form my experince.
As of right now my settings are as follows:
lex afm screw: I backed it all the way out and went 2 full turns in.
base fuel pressure: 41 psi (this is when the car is started cold and no vac line attached)
Also before I get flammed here are two good links for anyone looking for basic info on the lex afm/550 mod:
http://rob.carlile.home.mchsi.com/lexus/lexus1.htm
http://suprasonic.org/lexusriemer/lexusnotes.html
First let me list the mods I currently have on the car:
57 trim ct-26
precision 550cc injectors
lexus afm housing
aeromotive afpr
bypassed j-tube
k&n fipk
3" divorced downpipe recirculated from 935 and straight pipe the rest of the way back
2.5in hard pipes
spearco replica intercooler from drift motion
apexi safc 2 w/boom slang pnp harness
aem UEGO wideband
hks evc boost controller
walbro fuel pump
future modifications:
Converting the car to a MAP system (hks vpc, maft-pro, or map ecu 2).
Give the motor a good rebuild (cometic hg, arp studs, and all new gaskets and seals).
Now my problems:
Problem 1.) Over boosting issue:
UPDATED 4/18: Now that I have installed the divorced down pipe the boost creeping issue has gotten worse. Now the turbo will easily creep up to 14-15 psi and I will let off there. The boost controller is set at 10psi and the boost will hold there for some time, but around 4000 rpm it will start creeping. I have thought about just setting the boost controller and seeing what that does. Since the creep issue is coming from the waste gate on the ct26 being not efficient as needed maybe I can get the boost set to where the waste gate will do what it needs to.
UPDATED 5/3: Well I hit 17psi the other day while test driving, afr's were still safe, but I needed to get this figured out. Tested the actuator and everything seemed to function properly. The waste gate flapper moved freely. Here in the next week or so I am going to take the turbo off and try to enlarge the waste gate port on the turbo slightly and maybe even try and port the down pipe as well. I have my fingers crossed that this will fix the issue with over boosting.
UPDATED 7/13: Alright I have been enjoying the car for the past month, but I am still having my boost issue. I had the ddp recirculated and it helped some, the car now only creeps to 15-16psi. I am kind of torn between putting on a more resterictive exhaust or porting the wastegate on the turbo. Any imput on the similar situations would be apprecaited
Problem 2.) FIXED: Every time I start the car when it is cold the afr's are steady around 14.8-15.0 when the car gets warmed up they will start jumping around all across the board and if the computer is trying to correct. I know that until the car is warm the computer will correct with the TCCS.
UPDATE 4/18: Alright just as every one has been telling me I had to check my vf voltage so I did. This was very simple in the diagnostic port just put the positive end of a volt meter in the vf1 pin and ground the other where you like. I noticed that sometimes the car would show 2.35v, which means no correction. Other times it would start running rough and go straight to 5v, which means the TCCS is seeing a lean condition and trying to correct by making things richer. I raised the fuel pressure and went in on the afm screw a little, but nothing seems to help. I have heard that and the lex/550 mod idle is always going to be lean.
UPDATE 5/3: I went to checking the signals on the o2 sensor and afm. Turns out that when the car starts to stumble the afm signal drops out entirely. Going to replace the afm and go from there.
UPDATE 5/7: You know it pays to be a supra owner because like most of us you always have a good supply of back up parts just lying around that you can't make yourself get rid of. Well I went through my pile and had a used but good afm. Got it on the car, cleared the codes and adaptations, fired it up and it ran like a champ. This weekend I am going to check my vf voltage and hopefully get the idle tuned out some.
Problem 3.) FIXED: Problem with going lean under boost.
UPDATE 4/18:Alright after I got the walbro installed and replaced my fuel filter this cleared up this issue, I set my base fuel pressure w/o vac to 41 psi, which was around 40 with vac on, and I backed the afm screw all the way out and went one turn in. I drove the car so that the TCCS could make the corrections and now when I boost the afr's look good. They are in the 11's.
A few things I need to note:
1. I have not yet started messing with the safc because I have read that the stock ecu should control the basics of the mod and only to use the safc to fine tune.
I am open to suggestions that anyone may have and would like to know what base fuel pressure people are running with the lexafm/550's set-up and what the afm screw is set at.
UPDATES That are not related with the problems above:
UPDATE 5/3: Aright did a compression test today and all the numbers looked good and steady. Checked the torque on the headgasket bolts and all were right at 75ft lbs. I called the about dyno time and getting the car tuned the other day and hopefully after I get the few issues fixed that I am having with the car I will be getting the car tuned at around 14psi or so and finally getting to enjoy it.
UPDATE 5/17: Well with the car running a lot better I have been driving it some and trying to iron out all the small things. My vf at idle has always been reading 5v which means the car is doing a 20%+ fuel correction to richen up the mixture. I was doing some research and think I have found my problem, someone who has had the car before me has adjusted the throttle stop screw on the throttle body. This screw is suppose to be set by toyota from factory and not messed ever again. With this screw not being set correctly the tps reading is being thrown off, timing incorrect, and is causing many other small issues. I have a different throttle body on the way which is suppose to have the factory setting of the throttle stop screw, once I get it on, tps set, and timing set I will give an update on how the car runs. Oh, and the turbo is still needing to get pulled, but I am enjoying the car a little before it gets pulled apart again.
UPDATE 5/30: Alright finally got the throttle body in the mail (well 2nd throttle body, the first was missing the throttle stop screw completely). Checked the tps before I got it on the car and it was set perfect. Bolted everything up, cleared the codes, and fired up the car. Code 51 is gone, finally. I jumped TE1 and E1 and the base timing was set to 15 degrees. I set the timing to 10 degrees and went for a drive. Car drove great, no more stalling issues, but still has a small over boosting issue. Sometime in the next week or so I am taking the car to my tuner and seeing what he can accomplish with the car the way it is. I will hopefully be able to raise the boost high enough to where it doesn't over boost anymore. Oh, and a little side not the ddp has gotten old so I am going to the exhaust shop to see if the can recirculate it.
UPDATE 9/16: Got the car on the
Thanks
James
Over the past few months I have been reading and trying to figure out how to get my car running good on the lex afm/550 combo. I think I have finally got most of the fine tuning figured out. The car no longer stalls, pulls hard, and drivibility is good. If anyone has questions on this I will do my best to help with the information I have learned form my experince.
As of right now my settings are as follows:
lex afm screw: I backed it all the way out and went 2 full turns in.
base fuel pressure: 41 psi (this is when the car is started cold and no vac line attached)
Also before I get flammed here are two good links for anyone looking for basic info on the lex afm/550 mod:
http://rob.carlile.home.mchsi.com/lexus/lexus1.htm
http://suprasonic.org/lexusriemer/lexusnotes.html
First let me list the mods I currently have on the car:
57 trim ct-26
precision 550cc injectors
lexus afm housing
aeromotive afpr
bypassed j-tube
k&n fipk
3" divorced downpipe recirculated from 935 and straight pipe the rest of the way back
2.5in hard pipes
spearco replica intercooler from drift motion
apexi safc 2 w/boom slang pnp harness
aem UEGO wideband
hks evc boost controller
walbro fuel pump
future modifications:
Converting the car to a MAP system (hks vpc, maft-pro, or map ecu 2).
Give the motor a good rebuild (cometic hg, arp studs, and all new gaskets and seals).
Now my problems:
Problem 1.) Over boosting issue:
UPDATED 4/18: Now that I have installed the divorced down pipe the boost creeping issue has gotten worse. Now the turbo will easily creep up to 14-15 psi and I will let off there. The boost controller is set at 10psi and the boost will hold there for some time, but around 4000 rpm it will start creeping. I have thought about just setting the boost controller and seeing what that does. Since the creep issue is coming from the waste gate on the ct26 being not efficient as needed maybe I can get the boost set to where the waste gate will do what it needs to.
UPDATED 5/3: Well I hit 17psi the other day while test driving, afr's were still safe, but I needed to get this figured out. Tested the actuator and everything seemed to function properly. The waste gate flapper moved freely. Here in the next week or so I am going to take the turbo off and try to enlarge the waste gate port on the turbo slightly and maybe even try and port the down pipe as well. I have my fingers crossed that this will fix the issue with over boosting.
UPDATED 7/13: Alright I have been enjoying the car for the past month, but I am still having my boost issue. I had the ddp recirculated and it helped some, the car now only creeps to 15-16psi. I am kind of torn between putting on a more resterictive exhaust or porting the wastegate on the turbo. Any imput on the similar situations would be apprecaited
Problem 2.) FIXED: Every time I start the car when it is cold the afr's are steady around 14.8-15.0 when the car gets warmed up they will start jumping around all across the board and if the computer is trying to correct. I know that until the car is warm the computer will correct with the TCCS.
UPDATE 4/18: Alright just as every one has been telling me I had to check my vf voltage so I did. This was very simple in the diagnostic port just put the positive end of a volt meter in the vf1 pin and ground the other where you like. I noticed that sometimes the car would show 2.35v, which means no correction. Other times it would start running rough and go straight to 5v, which means the TCCS is seeing a lean condition and trying to correct by making things richer. I raised the fuel pressure and went in on the afm screw a little, but nothing seems to help. I have heard that and the lex/550 mod idle is always going to be lean.
UPDATE 5/3: I went to checking the signals on the o2 sensor and afm. Turns out that when the car starts to stumble the afm signal drops out entirely. Going to replace the afm and go from there.
UPDATE 5/7: You know it pays to be a supra owner because like most of us you always have a good supply of back up parts just lying around that you can't make yourself get rid of. Well I went through my pile and had a used but good afm. Got it on the car, cleared the codes and adaptations, fired it up and it ran like a champ. This weekend I am going to check my vf voltage and hopefully get the idle tuned out some.
Problem 3.) FIXED: Problem with going lean under boost.
UPDATE 4/18:Alright after I got the walbro installed and replaced my fuel filter this cleared up this issue, I set my base fuel pressure w/o vac to 41 psi, which was around 40 with vac on, and I backed the afm screw all the way out and went one turn in. I drove the car so that the TCCS could make the corrections and now when I boost the afr's look good. They are in the 11's.
A few things I need to note:
1. I have not yet started messing with the safc because I have read that the stock ecu should control the basics of the mod and only to use the safc to fine tune.
I am open to suggestions that anyone may have and would like to know what base fuel pressure people are running with the lexafm/550's set-up and what the afm screw is set at.
UPDATES That are not related with the problems above:
UPDATE 5/3: Aright did a compression test today and all the numbers looked good and steady. Checked the torque on the headgasket bolts and all were right at 75ft lbs. I called the about dyno time and getting the car tuned the other day and hopefully after I get the few issues fixed that I am having with the car I will be getting the car tuned at around 14psi or so and finally getting to enjoy it.
UPDATE 5/17: Well with the car running a lot better I have been driving it some and trying to iron out all the small things. My vf at idle has always been reading 5v which means the car is doing a 20%+ fuel correction to richen up the mixture. I was doing some research and think I have found my problem, someone who has had the car before me has adjusted the throttle stop screw on the throttle body. This screw is suppose to be set by toyota from factory and not messed ever again. With this screw not being set correctly the tps reading is being thrown off, timing incorrect, and is causing many other small issues. I have a different throttle body on the way which is suppose to have the factory setting of the throttle stop screw, once I get it on, tps set, and timing set I will give an update on how the car runs. Oh, and the turbo is still needing to get pulled, but I am enjoying the car a little before it gets pulled apart again.
UPDATE 5/30: Alright finally got the throttle body in the mail (well 2nd throttle body, the first was missing the throttle stop screw completely). Checked the tps before I got it on the car and it was set perfect. Bolted everything up, cleared the codes, and fired up the car. Code 51 is gone, finally. I jumped TE1 and E1 and the base timing was set to 15 degrees. I set the timing to 10 degrees and went for a drive. Car drove great, no more stalling issues, but still has a small over boosting issue. Sometime in the next week or so I am taking the car to my tuner and seeing what he can accomplish with the car the way it is. I will hopefully be able to raise the boost high enough to where it doesn't over boost anymore. Oh, and a little side not the ddp has gotten old so I am going to the exhaust shop to see if the can recirculate it.
UPDATE 9/16: Got the car on the
Thanks
James
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