1986 Nissan Pickup - Spontaneous Ignition Failure

[nfbriggs]

My 1986 Nissan pickup (2.4L inline 4 cylinder RWD engine) had the jumper cables reversed about a year and a half ago. The initial problem that occurred was that the fuel injectors and ECU were fried, so the engine would bog down and die. These items were replaced, but ECU was used from a junkyard.

 

The current problem arose about 3 months ago when it felt that I had run out of gas on the highway. The truck  bogged down and died and would not start. The mechanic said he cleaned out the fuel injectors and it seemed that the problem was fixed, but then it began to spontaneously not start, and it would bog down and die again just as it had done before. 

 

We found that when the engine did run, the exhaust side spark plugs would not fire, and when it wouldn't start, no spark plugs would fire. Gas seems to be getting to the engine because you can see fuel when you look down the throttle body after a good amount of cranking. We thought it was probably the distributor being fried from back when the cables were reversed and we replaced it, but it had the same symptoms. The actual ignition coils have the same resistance from all terminals to each other, but there is a transistor part on the sits on the housing of the coils that we thought could be damaged.

 

So we think the problem could lie in three parts:

1. The ignition coils/transistor part

2. The ECU - Unlikely because it was just replaced a year ago, albeit with a used one.

3. A bad connection somewhere.

 

What do you think is the most likely problem and is there anything that I am missing that could be the problem?

[datzenmike]

Replace the first fuse on the far left side of the fuse box regardless how good the old one looks..