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Thanks! It’s going to be my daily in the coming months so reliability was a main goal. I have one final kink I’m working out and I will detail how to get this setup with no check engine lights on a usdm spec car. Mine is a 2005 which seems to be ultra picky about the o2 sensors and not having any cats.
 

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Thanks! It’s going to be my daily in the coming months so reliability was a main goal. I have one final kink I’m working out and I will detail how to get this setup with no check engine lights on a usdm spec car. Mine is a 2005 which seems to be ultra picky about the o2 sensors and not having any cats.
If you could achieve this and explain how it is done you would be my hero! I am currently on the fence of selling my car cause I want to go turbo but have emissions to worry about. Please keep us updated!
 

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Will do! An rr-racing o2 conditioner is coming Monday. If all works as expected I will give the full details. I only have 2 o2 sensors but the wiring is a bit different than what I found online previously.
 

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Sorry to litter your thread anymore Pynoxim but do you think your fueling upgrades would work on a 1jzgte VVTI with a stock 2jzge VVTI ecu?

I am trying to come up with a way to do a very basic 1jzgte swap with a 2jzge ecu, and still pass emissions (basically a CEL test, no sniffer required). Basic, meaning just enough to get it running reliably....I would splice the two B1/B2S1 02 sensors together and use 02 sims for the S2's.
 

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Discussion Starter #105
Sorry to litter your thread anymore Pynoxim but do you think your fueling upgrades would work on a 1jzgte VVTI with a stock 2jzge VVTI ecu?

I am trying to come up with a way to do a very basic 1jzgte swap with a 2jzge ecu, and still pass emissions (basically a CEL test, no sniffer required). Basic, meaning just enough to get it running reliably....I would splice the two B1/B2S1 02 sensors together and use 02 sims for the S2's.
Well, I don't see why not although you would have to use the GE injectors and rail with an external 1:1 RRFPR and fairly low boost from the stock twins with the GE MAF and a Wideband just to keep your eye on the fuelling under part throttle and load. I don't see why it wouldn't work since the engines are similar in the way they run.
 

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Just checking in... so far after 4 trips back and forth to work which is about 27miles each way and a bunch of driving around town in between everything is looking good. The ecu finally seems happy as a clam. Fuel trims look great b1vsb2 and I have no codes. If it stays like this for the week I will make a post about how to keep this stuburn son of a gun happy.
 

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you guys are costing me some serious cash...........
 

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Discussion Starter #108
you guys are costing me some serious cash...........
Haha, sorry not sorry :laugh:

Just checking in... so far after 4 trips back and forth to work which is about 27miles each way and a bunch of driving around town in between everything is looking good. The ecu finally seems happy as a clam. Fuel trims look great b1vsb2 and I have no codes. If it stays like this for the week I will make a post about how to keep this stuburn son of a gun happy.
That's some amazing news man, this whole thread is a working proof of concept thread haha.
 

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This thread is what inspired me to start my build. It has proven what I already suspected. You can make safe,fun, and reliable power for well under the 10k everyone claims it costs to boost an is. Just don’t get greedy and stay within the limits and you should have some long lasting fun. I came in at around $1750 not including my exhaust system.

that engine bay looks factory
 

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Ok another day of commuting and bs’ing around town and all is green. So here is the trick. I currently have two o2 sensors in my Downpipe about 6 inches apart and say a foot or so from the turbo. The o2 sensor closest to the turbo is my bank 1 sensor. First we will talk signal wires. B1S1 and B2S1 signal wires are tied together at the ecu per the usual write ups. B1S2 and B2S2 signal wires are cut at the ecu. Harness side signal wire from whatever o2 you have plugged in as your “aftercat” sensor, which in my case is b1s2, is fed into an rr-racing o2 CONDITIONER. A conditioner gives the ecu live data from the exhaust stream instead of bogus up and down signaling from an o2 “sim” this is crucial from my testing. Ecu side b1s2 and b2s2 are paired and connected to the output of the rr-racing o2 conditioner. Now on the the heater wires. This is done at the ecu like the usual write ups show except one major difference. Instead of how the write ups show both front heater wires paired to the same sensor and both rear heater wires paired to the same sensor, I have them crossed. This way b1s1 and b2s1 are getting signals from diff o2 sensors and don’t have identical readings. This is what I’m assuming was causing the ecu to “chase its tail” with the fuel trims. So heater wiring is connected b1s1 to b2s2 and b2s1 to b1s2.

I about 80% confident I have this all sorted. I will post back after a week of commuting and if I see no check engine light or strangeness with my fuel trims drifting apart this problem is finally solved. I will try to make a fancy ecu wiring diagram for this madness at that point.

All “readiness” monitors have been set are are showing ok now for at least 150 miles.
 
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that engine bay looks factory
Hmmm... was that an accident? >:) “factory” looking engine bay and approx. 298hp. It’s almost like I was going for a stock version of another car Toyota put out except with 4doors...

On a serious note thanks for the compliments on the clean bay. I did take extra care with the layout to keep it simple and clean. Glad you guys took notice. It makes the extra time spent seem more worth it.
 
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Ok another day of commuting and bs’ing around town and all is green. So here is the trick. I currently have two o2 sensors in my Downpipe about 6 inches apart and say a foot or so from the turbo. The o2 sensor closest to the turbo is my bank 1 sensor. First we will talk signal wires. B1S1 and B2S1 signal wires are tied together at the ecu per the usual write ups. B1S2 and B2S2 signal wires are cut at the ecu. Harness side signal wire from whatever o2 you have plugged in as your “aftercat” sensor, which in my case is b1s2, is fed into an rr-racing o2 CONDITIONER. A conditioner gives the ecu live data from the exhaust stream instead of bogus up and down signaling from an o2 “sim” this is crucial from my testing. Ecu side b1s2 and b2s2 are paired and connected to the output of the rr-racing o2 conditioner. Now on the the heater wires. This is done at the ecu like the usual write ups show except one major difference. Instead of how the write ups show both front heater wires paired to the same sensor and both rear heater wires paired to the same sensor, I have them crossed. This way b1s1 and b2s1 are getting signals from diff o2 sensors and don’t have identical readings. This is what I’m assuming was causing the ecu to “chase its tail” with the fuel trims. So heater wiring is connected b1s1 to b2s2 and b2s1 to b1s2.

I about 80% confident I have this all sorted. I will post back after a week of commuting and if I see no check engine light or strangeness with my fuel trims drifting apart this problem is finally solved. I will try to make a fancy ecu wiring diagram for this madness at that point.

All “readiness” monitors have been set are are showing ok now for at least 150 miles.
You guys are keeping the dream alive. Seriously, piggybacks are headaches, and standalone's are difficult to pass emissions with. But THIS, this is feasible. Thank you all for investing your time in countless trials/error and research to figure this out and share the results with the rest of us. :grin:

I look forward to boosting mine in the future!:wink:
 

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Quick update: noticed an extremely slight drift in fuel trims today. One or two points max. It could stop here or continue to snowball. Miles will tell. Either way that’s over 200 miles and the car is still running exceptionally.
 

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Well i went for an ecu reset today :/ Fuel trims def. start to drift after the 250+ mile mark. In some load conditions i see bank 1 at -0.8 and bank 2 at +5.5 on the long term trims. I think this is very minor and doesn't seem to cause any drive ability issues but I'm thinking its not correct. Maybe someone can chime in and tell me im crazy? 250 miles still leaves plenty of time to clear all readiness checks for inspections purposes and I still had no fault codes in sight. I just didn't like what i was seeing fuel trim wise and may resort to reseting the ecu at every fill up. Let me do some more experimentation before it comes to that.
 

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Discussion Starter #115
When I get my car back I'll check the fuel trims and post a screenshot up here, perhaps we're both experiencing the same issues, but I don't think mine is as severe as yours. If I remember correctly my trims were around +2%, but that was over 10k miles.
 

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Ok cool ya maybe your setup can offer me some insight. I would expect to see negative fuel trim numbers in the low load out of boost sections seeing as the fuel pressure is bumped higher than stock and I’m not adding extra airflow. If I just check my fuel trims at idle I see a -13.5 on both banks for the whole 250 miles. That makes sense to me because of the extra fuel. But when I’m in light throttle cruise I see positive fuel trim numbers on one bank which can’t be right with the extra fuel I have added. Maybe it is though....
 

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Another 250+ miles. No check engine light and full readiness monitors. However fuel trims are no good after that amount of driving. The stock ecu just can’t figure out what to do without 2 o2 sensors in the turbo manifold before the turbo and I’m not interested in running a setup like that. I’m going to create a reversible ecu reset relay “black box” inside the fuse box on the two fuses that need to be pulled to reset the fuel trims. I’ll probably wire in a hidden kill switch at the same time. With a reversible setup like this when it come time for inspection I just remove the reset system and let the readiness monitors set a week prior to inspection. That’s the best we are going to get. Sorry guys. My post about o2 wiring is still valid if you want to be able to go through inspection.
 

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Discussion Starter #118
Well, in any case at least you experimented and came to a conclusion, that's what this is all about, figuring things out and the only way that's going to happen is to experiment. Thanks for going through all that effort man.
 

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Quick update... turns out the second time I tried to reset my fuel trims I didn’t wait long enough for the caps in the ecu to drain so it never reset them. My fuel trims at 350 miles are still holding what they were at about the 150mile mark and there is no knocking or drivability issues. I may retract my “failure” assumption. I’m going for it. Let’s see how they look at the 500+ mile mark. Afr under full boost has settled in at around 11.2-11.7 by redline at 6.5 psi. It pulls stronge and feels great with the IS300 5 speed auto and 4.1 diff. Idle is also as smooth as glass and floats between 14.5 and 15.1 afr.
 

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Quick update... turns out the second time I tried to reset my fuel trims I didn’t wait long enough for the caps in the ecu to drain so it never reset them. My fuel trims at 350 miles are still holding what they were at about the 150mile mark and there is no knocking or drivability issues. I may retract my “failure” assumption. I’m going for it. Let’s see how they look at the 500+ mile mark. Afr under full boost has settled in at around 11.2-11.7 by redline at 6.5 psi. It pulls stronge and feels great with the IS300 5 speed auto and 4.1 diff. Idle is also as smooth as glass and floats between 14.5 and 15.1 afr.
I may have missed it, but do you have any tranny mods?

I'd pretty much have the same build as you, NA-T + Auto & 4.1 LSD.
 
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