Bad ECU???

[supersupramk3]

What are symptoms of a bad ECU. I have been trying to get rid of this code 21 for 2 weeks now. I installed a new o2 denso, ohm'd all the wires at harness to the ecu and check the continuity (which all test out good). Could it be my ECU and if it is what are the symptoms and anything I could do to troubleshoot. I dont want to buy another ECU if I dont have to. Please give me some input. thx.

 

[T-MA71]

What are symptoms of a bad ECU. I have been trying to get rid of this code 21 for 2 weeks now. I installed a new o2 denso, ohm'd all the wires at harness to the ecu and check the continuity (which all test out good). Could it be my ECU and if it is what are the symptoms and anything I could do to troubleshoot. I dont want to buy another ECU if I dont have to. Please give me some input. thx.

Try pulling the EFI fuse for about 15 sec to "reset" the ecu. Then check if it shows up again.

 

[supersupramk3]

Try pulling the EFI fuse for about 15 sec to "reset" the ecu. Then check if it shows up again.

Yep tried that multiple times.

 

[dbsupra90]

the one and only ecu i've seen bad in 11 years playing with supras was causing an 02 code. i'd try to swap with someone if you have confirmed everything else.

 

[supersupramk3]

the one and only ecu i've seen bad in 11 years playing with supras was causing an 02 code. i'd try to swap with someone if you have confirmed everything else.

Yeah, I know Ive tried pretty much everything. Now Im not sure of the history of the prior owner. I think I have a jdm ecu, with a usdm harness and a jdm motor. Im not sure if this will have an impact on how the ecu is reading out the codes. Main thing is Ive got SMOG due in 1 week and the smog techs wont even run my car with a CEL on. This is a failed visual inspection automatically. I dont have a spare ECU, a buddy of mines has a
92t manual...but i think the ecu is different!

 

[dbsupra90]

if it's a gray plug and your car isn't auto it should be fine.

worst case you can unhook the bulb long enough to smog. altho throwing an 02 code don't know if it will pass. not familiar w/ cali testing

 

[supersupramk3]

*Bump*
I really surprised nobody can give me any suggestions/solutions...!

 

[san supra]

swapping the ecu was a suggestion and if that fixes it, there's your solution.

are you running rich? In my truck (22re) my puter used to throw a code because i was running rich.