Build US Spec. February 1990 Poverty 80 2uz/h151f swap

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matzell said:
Do you have a decent scanner so you can watch what the timing is doing while driving? I wonder if the VVT is working as designed. May not be getting timing advance as needed?
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Another member asked the same question. I was able to confirm the timing is advancing with rpm’s. It does appear to be working as it should. I am using Techstream as pointed out.

I appreciate the feedback.
 
Last night I was trying to collect some data for Tim in live stream and it didn’t go well. I need to back up though.

On Sunday night I tried swapping my second ecu to see if it performed differently. After swapping the ecu the pedal was dead no response and no trouble codes. I swapped the other ecu back in and no change the pedal was still dead.

Tim sent me the circuits to test, I tested continuity, didn’t find anything wrong all tests were good. After plugging everything in the pedal worked in full range idling in the garage. I tried to take it out for a drive and when I got to the main road the pedal was unresponsive again but I got two trouble codes this time, P0101 and P2111. I drove home with the pedal to the floor in first gear and it moved the truck just enough to get home but didn’t even register 5mph. It was a slow drive home to contemplate my choices.

My laptop fell off the seat when I turned around and broke the screen, so I cannot read tech stream any more until I fix or replace it.

I checked the throttle plate function after getting back and found that it opens fully when the pedal is pressed to the floor. The pedal appears to be communicating with the throttle body correctly.

It seems like every time one issue is solved another one is presented.

I think I may be nearing my limit for time and money on this engine. I really wanted the extra HP of the VVTI while still running regular gas. It just seems that with all the changes to the ecu to delete systems in order to simply it, something is not working. That is all I can come with anyway.

It has now been well over three years of trying to get it to run correctly. I have talked to a number of Toyota techs of varying skill who have been extremely helpful and other members that have done similar builds. They have all helped me test and eliminate potential causes. It does not appear that there is anything wrong with the engine or sensors. The most common conclusion is the problem is with the ecu.

I know Tim is planning to flash the second ECU to match or mimic an ecu from the South African market where the 2uz VVTI did not come with SAI. If it does not work I may be looking at scrapping the VVTI engine.

I really want to enjoy using this 80 rather chasing endless issues with the VVTI, at some point this either works or it doesn’t.
 
White Stripe said:
Do you have a speed sensor for the toyota ecm? What gear is it locked into?
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It is powered in 2nd gear. There is no speed sensor wired on my setup. Tim’s harness is built such that there is not a provision for the sensor.
 
When the pedal was/is dead, can you tell if it reads on the scanner? It should match the throttle. idle I would think would be 2-5% and then they should follow each other. Push the pedal down slow and watch the numbers. If you snap the throttle it will be a slight delay in keeping up. Just another thought once you get your computer screen fixed.
 
White Stripe said:
Is that the normal way to do it? Being in second gear and no speed sensor signal might confuse the ecu is my thought.
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Tim has told me he has built more than a dozen of these and this is how he does it. My build and one other are the only two that seem to be having problems. In regard to how the ecu is wired and programmed I am defaulting to Tim, since he is doing things to the ecu I cannot see or access. The stand alone harness and ecu programming is what I paid for and it does not match the oem diagram anymore, so I am hesitant to mess with his work unless I doing so at his direction.
 
matzell said:
When the pedal was/is dead, can you tell if it reads on the scanner? It should match the throttle. idle I would think would be 2-5% and then they should follow each other. Push the pedal down slow and watch the numbers. If you snap the throttle it will be a slight delay in keeping up. Just another thought once you get your computer screen fixed.
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I believe I looked at this a while ago and did not see anything wrong. It was a while ago during this build, so I cannot recall the specifics. I will look at it again after I can see my Techstream again.
 
Tank5 said:
Tim has told me he has built more than a dozen of these and this is how he does it. My build and one other are the only two that seem to be having problems. In regard to how the ecu is wired and programmed I am defaulting to Tim, since he is doing things to the ecu I cannot see or access. The stand alone harness and ecu programming is what I paid for and it does not match the oem diagram anymore, so I am hesitant to mess with his work unless I doing so at his direction.
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When your driving in gear and floor it, what is the map reading in live data?
 
It sounds like you found the real limp mode. The slow to to accelerate but still mostly drive ok just extremely slow is like stage 1, the completely dead no more than 5mph is true limp mode. Something is going on with your tune/ECU. Having a vehicle speed sensor (VSS) is not hard so I'm not sure why he is bypassing it, that would be the first place I'd start. Fooling the ECU into thinking it's always in 2nd with no other sensors working seems like an odd choice, I'm surprised it even starts.

Him tuning more than a dozen manual trans 2UZ with VVTI is hard to believe, that's not a common setup. Maybe automatics.
 
I don’t know if this would be helpful, but here’s the new car features document showing all the engine and sensor changes from the 2005 non-vvti to the 2006 vvti 2uzfe from CruiserCult. Lots of good info. I could see a small error in ecu programming or communication that would cause issues with the vvti engine

2006 New Car Features

Kyle
 
Skter505 said:
It sounds like you found the real limp mode. The slow to to accelerate but still mostly drive ok just extremely slow is like stage 1, the completely dead no more than 5mph is true limp mode. Something is going on with your tune/ECU. Having a vehicle speed sensor (VSS) is not hard so I'm not sure why he is bypassing it, that would be the first place I'd start. Fooling the ECU into thinking it's always in 2nd with no other sensors working seems like an odd choice, I'm surprised it even starts.

Him tuning more than a dozen manual trans 2UZ with VVTI is hard to believe, that's not a common setup. Maybe automatics.
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I agree It seems like I found the definitive limp mode.

As for what Tim has or has done I can’t say, just sharing what he told me. I didn’t get a break down of the various configurations he built for.
 
FzjTaz said:
I don’t know if this would be helpful, but here’s the new car features document showing all the engine and sensor changes from the 2005 non-vvti to the 2006 vvti 2uzfe from CruiserCult. Lots of good info. I could see a small error in ecu programming or communication that would cause issues with the vvti engine

2006 New Car Features

Kyle
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Thanks for posting this up, I will read through it to see if something stands out.
 
White Stripe said:
When your driving in gear and floor it, what is the map reading in live data?
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Do mean the MAF? There is no data in the live data that refers to the MAP that recognize. I seem to recall that this engine does have a map sensor but the closest thing to it is the pressure sensor attached to the SAI which was deleted along with the SAI.

If I am wrong please correct me.
 
I am not a 2uz expert. I was thinking if you had live data manifold pressure you could see if the throttle body is opening while under load. You could also do it with a vacuum gauge while you drive. My guess too is its in limp mode because the issue is somewhere in the tune. Personally I would take the vehicle to a tuner and let them check out the tune with the truck in front of them. It might be easier to work out the issue. Maybe you've already tried some of these ideas though.
 
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At this point, is it perhaps time for a 5.3/manual swap? I love my VVTI 2UZ-FE to death but the LS engines seem much more compact and easier to swap.
 
Rednexus said:
At this point, is it perhaps time for a 5.3/manual swap? I love my VVTI 2UZ-FE to death but the LS engines seem much more compact and easier to swap.
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I don’t have anything against an LS swap but it is just not what I want. If I give up on the vvti I would most likely go with a Supercharged non-vvti 2uz. I just don’t want to pay for the premium fuel that comes with the Superchsrger.

If I was to abandon the 2uz series all together I would probably go back to diesel before LS.

I still have a few other options to potentially work through before I abandon the VVTI.

Lucky for me I have a 2uz swapped FJ45 and a Tacoma to drive while I continue to work through this.
 
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