Hi, this is the car:

4Runner 1995 two wheel drive 3VZ engine, mechanically very good, lots of things replaced just 4 months ago,approx. 200K miles:

Ignition wires, plugs, new distributor, igniter, ECM (used ECM from eBay)
That was because the engine stopped dead at a traffic light.
We did the above work ourselves and run horrible until we the installed an used ECM from eBay. So for 4 months has been running well until last week.....

Run perfect after repairs 4 months ago, but the car died on the road last week.
Again as before the no NE error, and would not even start at all.
Also the starter quit now so replaced it yesterday and checked all resistance at ECM wire bundle and the NE-G-minus ad also the G1 and G2 resistances OK. Has a new distributor.
Tried today with the old ECM and just runs horrible as before,which makes sense to me that the ECM is again the problem as before.

Now the Questions:
Is this a common problems on those ECM's or just bad luck with the also 25 yrs. old from eBay? We cannot afford the $600 new.
The error code is 12, No NE Signal to the ECM. In the past I checked the signal reaching the ECM using laptop Picoscope and the signals reached the ECM, I tried to twist a little the pins on the ECM to see if it was a bad contact problem, but it acts as this is not the problem. If I insert the original ECM runs very crappy, and the second ECM just failed last week will not run at all with Code 12.
The car is from a very good friend, we both retired(read fixed income) and we cannot afford to take this old car for repairs or expensive super-diagnostic.

Any thoughts, experiences or suggestions?
Thanks

 

Post in the general truck forum for 86 to 95s. This is for build threads..

 

There are three parts in play here, the signal generator (distributor coil) NE signal, the ECU (wave shaper), and the ignitor..

Attach your Pico to the output from the ECU to the ignitor (IGT) and compare it with the distributor (NE) signal.

 

Yota ECUs are known for being stout. If you’re on your 2nd you need to trouble shoot why.

it is also possible that it’s not ECU at all but a wiring issue in a 25yr old truck is not unheard of. Intermittent shorts are the worst to track down. Be it a loose connector end or a damaged wire, a PITA at best.