amoebiasis

Hello everyone. I have an issue where when I am cruising on the highway at around 70mph, my car "bucks". It sorta like stumbles for a second then continues on as before. It does this randomly. It might stumble several times in quick succession or it might do it once every couple of seconds. It also seems that it gets worse the longer I drive, but I am not sure about this. Maybe engine temp has something to do with it). The only thing I am sure about is that it is driving me crazy. This is my dd and I drive it 45min everyday on the highway to work and from work. I have been trying to fix it for days now and have had made no progress.

I have had this issue before and it has always been a bad connection between the ecu and the sensors in the distributor (crank, cylinder, TDC). I thought that I fixed the problem for good last year when I replaced the distributor connector with a new Deutsch connector, but I guess not.

What I have done so far:
1. checked and double/tripled checked the sensors according to the helms manual, including the resistance of each sensor at the ecu
2. checked the resistance of each sensor wire between the ecu and the distributor, while shaking the engine/ecu harness to see if there is a loose wire
3. replaced the ecu pins on the engine harness side with new pins from the dealership
4. resoldered the pins in the conversion harness (running the ITR ecu)
5. checked the pins in the ecu conversion harness on the ecu side
6. checked the Deutsch connector and made sure each pin is making a good connection
7. tried a different ecu

To add since this is relevant, during testing i broke one of the male pins in the conversions harness for the orange sensor wire. I repaired it and retested. Also the reason I was focusing more on the ecu connections is that I damaged some of the pins in the harness in my frustration. That is why I went ahead and replaced the pins with new ones. The ones I got from the dealer was slightly different in appearance but they seem to work fine.

Everything I do checks out. No matter how hard I shake the harness around the most variance I get in the resistance is .1ohms. Each sensor gave me a resistance of around 450ohms, within the tolerance (I believe the range the manual gives is 350-700).

I am starting to think it might be something else but I do not know what else might cause this. I might just bypass the entire harness and connect the distributor wires straight to the ecu and see if that fixes it. Like I said this problem is driving me crazy and I am extremely frustrated trying to fix it. Any help will be greatly appreciated.

amoebiasis

I forgot to add that it is a 96 spec JDM ITR swap running the OBD2 ITR ecu with a conversion harness and wire tuck. Also, I guess a more technically correct term would be "receptacle" not "pin".

Also the wires leading from the distributor connector are soldered to the main harness under the intake manifold. There might be a bad connection there somewhere but it is near impossible to get to it. I would need to take the intake manifold off to check it, which I might do this weekend. However I should have been able to detect a bad connection with the resistance testing right?, especially when I was shaking the wires.

Again thanks for any help, and sorry for the long post. I wanted to be detailed.

amoebiasis

So for an update, I though that maybe it was the TPS so I unplugged it going home one day and it didn't mess up again all the way home. However the next morning after about 20-30 min of driving it started again, and this time it was doing it so bad I had to stop. It was literally shaking me back and forward.

I plugged the sensor back in. While I was in there I tied up the dizzy connector with a zip tie since it was just lying there on top of the radiator hose. This was two days ago and it has not messed up since. Maybe that connector was getting too hot? I don't know but I do not believe it is gone for good. I might cut that zip tie back off and see if it starts again.

I went ahead and ordered a new fuel filter as well since I am due for a replacement anyway. I do not believe that is the cause but who knows, maybe I will get lucky.