Supra Forums banner

1 - 16 of 16 Posts

·
95 Hardtopper X 2
Joined
·
1,709 Posts
Discussion Starter #1
So happy with my car thought I should share the good news maybe it will help some of you out there.
So I own a 95 Hardtop Turbo, some people might know about this lightweight Supra as it belonged to Steve Theodore. Its a single with an external pump, S-AFC/VPC and stock injectors. For some reason the car would always run too lean like 13.5-12.9 AFR's under full boost from 4K to redline. Nothing seem to fix the problem no matter how much I played with the SAFC or VPC gain. Now the carzy part, I put on a OBDII and the car is running 11.0-11.5 under boost, idling fine and everything, my EGT's under full throtlle dropped from 790's to 680's. I thought it might help to go OBDII but no way in hell I was expecting anything like this.
So to anybody having any issues like mine definately give the OBDII a try.
 

·
HIGH ON PSI
Joined
·
1,040 Posts
i dont think the OBD1 ecu was bad as i had a very similar problem. back when i was OBD1 the car was always slightly lean (around 12.5-12.9) from about 4500-5600rpm, no matter how much i richen that area out. swapped out to OBD2 and was running 11.1 all the way through WOT. as was posted above, many others have claimed this problem.
 

·
Administrator
Joined
·
17,224 Posts
Keep in mind that this specific Supra has a fairly unique fuel system and comparisons are a bit more difficult. I just about dropped the phone when Mani called me to tell me what a huge impact the new ECU had!

Well done bud! Now you can focus on other things and have some fun. :)

Steve T.
 

·
95 Hardtopper X 2
Joined
·
1,709 Posts
Discussion Starter #7
Steve Theodore said:
Keep in mind that this specific Supra has a fairly unique fuel system and comparisons are a bit more difficult. I just about dropped the phone when Mani called me to tell me what a huge impact the new ECU had!

Well done bud! Now you can focus on other things and have some fun. :)

Steve T.
Happy with the car, took it out last night and it was running real strong and for the first time I shot out flames!!
 

·
Team 10+ Year Member
Joined
·
3,510 Posts
Heard you guys had some fun out at DPA last night Mani.. I was talking to Eric.. whenever someone gets me video of the "closed course" :D action I will host it for you guys.. glad to hear you got the car running right! I will most likely meet you sometime this summer when Im back up in NJ visiting...until then happy boosting!
 

·
95 Hardtopper X 2
Joined
·
1,709 Posts
Discussion Starter #9
Dan94TT said:
Heard you guys had some fun out at DPA last night Mani.. I was talking to Eric.. whenever someone gets me video of the "closed course" :D action I will host it for you guys.. glad to hear you got the car running right! I will most likely meet you sometime this summer when Im back up in NJ visiting...until then happy boosting!
Definately come up to NY this summer there are alot of high hp Supras here now. I dont think that the two T-78 equipped Supras want that video hosted if you know what I mean :D.
 

·
HIGH ON PSI
Joined
·
1,040 Posts
MANI009 said:
Definately come up to NY this summer there are alot of high hp Supras here now. I dont think that the two T-78 equipped Supras want that video hosted if you know what I mean :D.
post it mani, im not ashamed!! your jenny craig supra is fast!!! on a side note i went out and got some 110 and cranked it to a more respectable 18psi and boy let me tell yah you better watch out!!! tonight im going to try 21-22 if i have enough courage. :D
 

·
Team 10+ Year Member
Joined
·
3,510 Posts
My T-78 buddies .. I dont mind what they think.. I want the footage!
 

·
Registered
Joined
·
2,291 Posts
Tep I also swaped in an OBD2 ECU, fixed my lean spot right up. The one problem I had is the OBD2 ecu doesn't control the o2 sensor heater correctly which will cause the car to idle very rich when sitting for awhile as the o2 sensor cools too much. AFAIK there has been no real conclusion as to why this is, and the current solution is to ground the o2 heater so that it is on all the time. So far I have no problems running like this.
 

·
HIGH ON PSI
Joined
·
1,040 Posts
hey josh, that info was good to know! my idle has been acting exactly as you describe and i thought it might be that my O2 sensor was on the way out since i do run leaded fuel occasionally. whenever it begins to idle rich does it cause a lope in the idle? im wondering because that is what is happening to mine and would like to know if might be from another cause. also, will grounding the o2 sensor shorten the life of the sensor?


PS- i remember speaking to you about the OBD1 lean spot back at XX Tuning over the summer. hope your car is running well!! :)
 

·
Registered
Joined
·
2,291 Posts
NYC 93-2JZGTE said:
hey josh, that info was good to know! my idle has been acting exactly as you describe and i thought it might be that my O2 sensor was on the way out since i do run leaded fuel occasionally. whenever it begins to idle rich does it cause a lope in the idle? im wondering because that is what is happening to mine and would like to know if might be from another cause. also, will grounding the o2 sensor shorten the life of the sensor?


PS- i remember speaking to you about the OBD1 lean spot back at XX Tuning over the summer. hope your car is running well!! :)
Ah, I remember you now.

If I remember correctly it did start to idle rough when it would go into it's over rich mode. I've talked to a couple other people who have done the swap and they all have the o2 heating issue. I believe it may shorten the life of the sensor to have the heater running all the time, but so far so good for me.
I haven't driven may car is months now, hopefully the weather will stay nice and I'll get it out soon.
 
1 - 16 of 16 Posts
Top