I have an '01 that's having some problems currently. It threw a PO325 which is knock sensor 1 bank 1. I replaced both sensors and the harness only to have it throw a PO325 again shortly after fixing it. Everything is replaced and plugged in. The ecu has already gone out once. Could the ecu really be bad again? Any ideas? Mine is supercharged with the URD 7th injector kit. Could the URD computer be causing problems?

 

Were the sensors OEM?

 

Import direct from O'reilly, so yes. They are Matsu˟˟˟˟a (matsus h i ta, its editing for language lol) which is the OEM spec. On top of that, the malfunction is still on the same bank (bank 1), I replaced both sensors, so if the sensors were bad, I would expect to see a bank 2 malfunction as well. My computer has already gone out once before (it would throw a code for throttle position circuit). I replaced the throttle body and it didn't fix the problem, I even took it to the dealership and they couldn't figure it out. Replaced the ECU and bam, no more problems. I'm wondering if there is an underlying electrical problem causing the computer to go out. I have the 7th injector computer piggy back, any way this could be causing problems? Another quirk with my runner is, when in drive, the tail lights, front corner lights and my pillar gauges all light up (headlights off). They don't fully light up, they are dim. There has to be a short somewhere in the system. I'm not sure if this could be causing my ecu problems. I've tried to chase that issue down and can't locate it...

 

I don't think these ECU's have a history of "going out" like Mitsubishi with leaking capacitors, perhaps everything is working perfectly electrically and you are experiencing Knock due to a lean condition or perhaps internal engine wear, Could be a loose component in the engine bay setting off the knock sensor aswell. Maybe the piggy back is leaning you out, or maybe your to rich which can also cause knock, lots to consider with a modified rig.

 

Yeah, your engine may actually be knocking. Using highest grade fuel available? 7th injector working properly? Spark plug condition?

 

I run an afr gauge and my air fuel ratio is actually very stable. It honestly never runs lean and under boost runs around 11.2 which is good for boost conditions. Additionally, this isn't the code I should be getting if it was a true knock. I should be getting a misfire code. This is a circuit code which means it's a malfunction somewhere along the electronics. I'm just going to buy another computer for $100 at a yard and give it a go. The sensors are new and I tested the harness running to the ecu. Everything checks out and I don't really think you can test an ecu, other than swapping a new one in.

 

Ah, you're right http://www.parksoffroad.com/tacomamo...e/cip0325p.pdf If you have easy access to and ECU, go for it. You very rarely ever see a 5vz ECU go bad.

 

It still might be worthwhile to swap the sensors side-to-side. Anything in this world can be bad out of the box. Might be rare, but it happens. Plus, you can check for bent pins in the connectors. That happens, too, even on new harnesses.

 

Its a huge job to take all the engine components off to get down there. I think it's worth the $100 to swap the computer and see if that's the problem.

 

Unless you have a WB02 I would not trust the AFR, it is really only telling you that the 02 sensor is operating properly, it doesn't give you true fuel ratio unless it is wideband. Maybe clean up all your engine and ECU grounds, maybe you have water dripping on your ECU causing issues. Try another ECU 3rd time may be the charm.

 

Yeah it's an aem wideband. Narrowband is useless, my afr readings are real. It's just started something else. It won't let me shift out of park anymore without pushing the override. My brake lights work so the park safety should disengage. Not sure wtf is going on here.