2000 Frontier problems

[mr_honez]

I'm sorry if my first post here is a problem post, but I don't know where else to turn.....

What I'm eventually finding out is that Nissan in their grand wisdom has made approximately 4 billion different ECM's for the 1st gen Frontier and NONE will work in my truck. I've tried for two weeks looking for one but I haven't had any success. It's just a 3.3L V6 AT 4X4 CC that I see everywhere, but since my production date is 3/00- no one seems to have it, and no body seems to ever have SEEN one. Ever. It seems my truck was the only one ever made then. I can have one special ordered for $800 from Nissan, but that's it so far- And I'd rather burn the truck first. I can't see spending that kind of money on something that may blow up or not work at all. I have run out of options as far as this is concerned, if anyone knows anything about the ECM from this truck I would be extremely grateful and appreciated. My ECM number is: (On Top) MECM W755 A1 0224 (SIDE) MECM W755 A1 3788. Why two different numbers? Even Nissan couldn't tell me.

The reason I believe my ECU doesn't work is that my Auto Analyzer (CP9180) wont connect to it now- Doesn't even see it when I hook up the ODBII plug. Truck wont start, no spark at the plugs, and one of the relays under the dash is buzzing- never has before the truck died. The relay checks out but I have no clue to what it goes to. There are three together- I know one is the flasher relay (and it looks different) but the other two are blue and all are to the right of the steering column. I've checked and/or replaced the distributor, rotor, wires, plugs, and checked underhood wires to see if something was amiss. I now have most of the dash removed from the truck and laying about the garage. I'm trying to see if there is a short in a wire under the dash, but I still have the other control boxes connected in case I need to try to start the truck. I haven't found anything yet, and as you can see, it's driving me crazy. I hate having to ride my motorcycle in the rain.

A little history:

The truck has been mostly a good truck until now- 189,000 miles, burns no oil, ran like a champ until it died (Or started dying). About little more than a month ago I noticed that it stumbled a little at idle. I thought no big deal, just maybe a little water in the gas, so I put some water remover and premium gas in it but the problem never went away. It just got worse, it would just die intermittently for no reason and with no check engine codes. It then started to die while running at low speeds, (actually driving) Then finally it died while at highway speeds (3500 rpm and under). It would usually crank right back up but sometimes would die again immediately (I would be in neutral) Most of the time it would stay running for a while and then die again. But it got worse, and started dying more frequently. It didn't matter if I was on the gas or coasting, it would die, though when it was cold it never died. I don't know if that was coincidence or not. I managed to keep it running and getting home by turning off OD and holding it above 3500 rpm in neutral. Thinking it was a fuel problem I checked the fuel pressure while it was parked and when it died the pressure was at 40-45 psi and so that 's not the problem. I did change the fuel filter, pressure regulator, and the PCV valve though to make sure. I still haven't gotten a code by this time either. To check if I could get one I pulled a plug wire and the check engine light did come on then. Then the final day of running arrived. I had to take my son to school a few miles away and it was running great (hadn't died once yet) but as soon as I dropped him off it died. Then died again, then again. I managed to get it to the local Walmart parking lot and it never started again, but the relay started buzzing now whenever the ignition gets turned on. The check engine light did come on when the ignition was switched on and the ECM was plugged in, and doesn't now when the ECM is out and the key is on. (though the relay does not buzz now since the ECM is out)

I hope that I've given enough info on this to help someone help me. If there is something I can answer I'll gladly do it. I know this is a book but like I said, I'm out of options at this point. Thanks for reading, and sorry again for the long first post.

C.j.

[mike]

Sound like a short in the system.

Start disconnecting sensors (O2, MAF, etc..) and see if the relay stops buzzing.

[mr_honez]

Originally Posted by mike

Sound like a short in the system.

Start disconnecting sensors (O2, MAF, etc..) and see if the relay stops buzzing.

Thanks Mike for answering, I will try that tomorrow.

[CRDLIBERTY]

do the actum razor thingy simplist problem could be a solution. Check your batter cables mine are ruined and need replacing right now 2000. Check your fuel pump relay, fuel pump fuse? I doubt you need new ecm.

[mr_honez]

Originally Posted by CRDLIBERTY

do the actum razor thingy simplist problem could be a solution. Check your batter cables mine are ruined and need replacing right now 2000. Check your fuel pump relay, fuel pump fuse? I doubt you need new ecm.

CRD thanks for the reply, but I failed to mention that I replaced the battery, cables, and terminals in the first post. I do have fuel though, that much I do know. I installed a fuel pressure fitting on the fuel line so I know the pump and relay works. I'm doing a ignition wire short search now. I'm trying to read the wiring diagram but I'm not making that much headway understanding it.

[FitzIngarage]

You might try Auto & Truck Electronics . Some of us on a Mitsubishi forum have used them with great success (some '90s Mitsus suffer from leaky capacitors in their ECUs).

[CRDLIBERTY]

Have you looked for every ground on the vehicle? Take all the harnesses apart that might apply and re click them in.

[mr_honez]

Originally Posted by CRDLIBERTY

Have you looked for every ground on the vehicle? Take all the harnesses apart that might apply and re click them in.

CRD I am doing that right now. I have my entire dash out now (heck the entire front of the cab sits outside the truck now) and am looking for any ground points. I am also removing and plugging back in all the connectors I can find. Thanks for helping me, I really, really appreciate it.

Cj

[Titanws6]

Longshot here, but my started to die in traffic as well, mostly when I would come to a stop. Someone recommmended I clean the MAF, I did, and it has been running just fine ever since. Maybe try cleaning this, see what happens. Looks like you've explored every other option, good luck.

[cargirl]

hay there sounds like your jumping the gun. you have fuel preshure. cheak for spark withspark tester. cheak for injector fire at one cyl with injector test lamp cheap and simple. if no injector siginal unplug all and recheak the light 1 bad injector can shut down the hole system.also go around and disconect sensors 1 at a time a bad sensor can shut it down just as easy.99% of no starts are under hood. bbut non of this will work if the dash is in the front seat. you need to reinstall that first.also dont forget to cheak the fusable links. always keep every thing pluged in and disconect one thing at a time.I learned that the hard way good luck