So here is the story. i own a 1989 toyota supra turbo. the problem i am having is the voltage at idl and e2 at the ecu. When i probe these leads i get 10 volts instead of the 4-6 that toyota calls for. when i unplug the ect for the transmission the voltage across idl and e2 drops to 5.2v. this is where it is supposed to be. Anyone know what the problem may be.????? please someone help i am ripping my hair out wondering where the problem may lay. thanks
weird tps voltage problem
- Thread starter 89toyotasupra
- Start date
the voltage in the manual which states to test the computer for problems should be 4-6v at ecu pins but im getting 10 volts. when i unplug the ect ecu the voltage between idl and e2 goes to 5v. it seems there may be something wrong with the ect computer. The car is running rich. the wideband reads 12 and before i took the manifold off to repair the block the afr was 14.7. everything is hooked back up and the knock sensors were rewired with shielded wire. tps adjusted to spec. i did have the battery disconnected for a couple days. does the computer take time to relearn? if so how long does it take? should not take to long. Thanks
i was just wondering because it has to do with the tps. i was just curious. i know its not the reason the car is running rich. the computer needs to relearn the fuel map since the battery was disconnected for such a long time. i think at least. from what i have been hearing. is this correct.
No, it's not correct. Do you think these cars run that rich every time the battery is disconnected? Do you think the factory had to "teach" each one after they built it?
I was just wondering since you seemed to be implying the TPS has something to do with the problems you are having. I mean, that's the question you were asked wasn't it?
I was just wondering since you seemed to be implying the TPS has something to do with the problems you are having. I mean, that's the question you were asked wasn't it?
this is what i found quote by quote
"think I finally found an answer to this: ~20min
from: http://alflash.narod.ru/vf1.htm
For the ECM to relearn the value, the vehicle must be driven in closed-loop, feedback operation for a certain amount of time. The amount of time will vary depending on the engine and the type of conditions the vehicle is driven in.
If memory is lost for D-type systems, it may take up to 20 minutes for strategy to be re-learned, depending upon altitude. Airflow meter types are able to relearn faster."
thats what i found on reading different forums
"think I finally found an answer to this: ~20min
from: http://alflash.narod.ru/vf1.htm
For the ECM to relearn the value, the vehicle must be driven in closed-loop, feedback operation for a certain amount of time. The amount of time will vary depending on the engine and the type of conditions the vehicle is driven in.
If memory is lost for D-type systems, it may take up to 20 minutes for strategy to be re-learned, depending upon altitude. Airflow meter types are able to relearn faster."
thats what i found on reading different forums
All depends on what's been done to the car from stock, standard I'd expect the error to be rich but don't know for sure.
the car is mostly stock has a 3inch downpipe and thats about it. but before i took the manifold off to repair the block the afr read about 14.7 and now it reads 12.7 or 12.4. i do have the wideband gauge
Go back and look at EVERYTHING you touched...
02 sensor plugged in and working?
it's NOT rocket surgery.
02 sensor plugged in and working?
it's NOT rocket surgery.
ya i figured that much. lol. adjusted the tps properly and within spec. rewired the knock sensors with shielded wire and i checked continuity between each end. i started to take apart the harness to look for any breaks in the wires and found a broken wire on the o2 sensor right by the turbo but had no code for it. i think it was the shielded wire for the o2 sensor that probably being the signal wire. it should have thrown a code
yep the engine is up to fully operating temperature. i know because the electric fan turns on. but i am going to have to check timing again when i get it all back together. just fixed the wire to the oxygen sensor so we will see how it runs. upper radiator hose on order and front main seal is on order to.
89toyotasupra;1845758 said:
Just for refrence, the car is programed from the factory. The only thing it learns is to respond to owners. It doesn't learn its map, it writes to it based on you, and that is a correction for doing something abnormal. And we all drive it hard, don't take that personal.
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so what would cause it to run rich? oxygen sensor, tps, knock sensors, timing. There were no boost leaks that i could see. i did not get any codes and the tps is ok and working. would not allow me to set the base timing to 10. knock sensors are rewired.
89toyotasupra;1845914 said:
Not enough air for the volume of fuel. You have to find that yourself, or pay somebody competent to do it for you.