240SX Harness issues???

[S13Teddy]

Hey guys,

Well I've been having some major issues with my car since April 2006 when I bought it. It was pre-swapped with an SR red top when I bought it. It did not run at the time.

The prev. owner said it did not start because he had an alarm installed, and that it shorted out the ECU. Supposedly, the ECU was bad.

So I brought it to a garage and he got it fixed. We put in a new ECU and drove the car from Pasadena to Torrance on the freeways, no problem. We also kept the old ECU just for kicks.

A few months later, my dad needed the ECU out of my car for his, so I pulled it out. I was on my way to bring it to him when he called me to let me know that he got his car to start and he did not need it anymore, so I brough it back.

I was curious to know what would happen, so before throwing my ECU back in, I decided to put in the old ECU. Amazingly, the car started right up. I pulled it out thinking "Score! I have 2 ECUs!!"

I threw my new one back in, and.....what the hell. The car no longer starts. I tried to put the old one back in, and no luck with that either. It now seemed as though both ECUs were shot.

One day I had the bright idea of thinking the igniter chip was bad, so I got a new one. I pugged it in, and WOAH! It starts again.

The next day I take it down the street, and the car just dies. It wasn't like a stall, it was like, the motor was still running kinda, but I couldn't give it gas. The car would not accelerate. So it just slowly came to a halt.

Well after 6 months, I was with a few friends, and we decided to figure out WTF the problem is. Now get this. We plugged the old ECU in, and it fired right up.

I drove the car on and off, just going around the block. One day I was driving on a street behind my house, and the POS died again, the same way it did the first time. This time, I tried plugging the ECUs back in, none would work. I went to R&D Factory and bought a new ECU from them (62) and plugged it in. I tried to start it, and it only cranked, but did not fire. Then I got the burnt smell in the car, and VOILA! I've burnt my 3rd ECU.

Now that you've taken the time to fully read my nice story, I need help to diagnose this stupid thing.

My best bet is that the harness is screwed up. I'm thinking of checking it pin-by-pin with a voltmeter, and fixing it, but I'm not sure.

What do you guys think is the problem??? I really need help because I really need a car again, and this is the only I have.

Thanks a lot

[evil_intent]

and i'm assuming we're talking sr?

[S13Teddy]

Yes. SR20 red top

[sil80S13]

ur baD u should of learn, check all ur grounds. replace harness. easy as that.

[S13Teddy]

ok. anything else? Do i really need to get a new harness, or can I just cheack all the wires in this one?

[180fan]

ok and aside from just switching the ecu you did what else to try to diagnose the problem?

are your cylinders flooding by any chance?

[S13Teddy]

I'm pretty sure it's electrical to be honest. As soon as I changed the ECU it fired back up. ECUs can fix flooded cylinders last time I checked. haha.