2G Talon troubles

[Boostedmm17]

Okay so to start off me and my buddy replaced the bottom end in his 95 talon. Along with that we install a safc. Well we finally have it finished and it runs like dog crap. It idles at 1200-1500rpm, blows smoke and sometimes it backfires. The idle doesn't change if you disconnect the front o2,maf, ECU temp sensor.

So I checked the check engine codes and I got this p0100,p0115,p0110,p0105. Now I don't believe these just up and took a dump. The car only has 48k on everything except the bottom end. So I'm hoping some can chime in on this, because I'm at the end of what i know.

 

[pauleyman]

First three codes are probably because you try to run it without the mass air sensor plugged in as all three of those codes are within the mass air sensor. The last code is for engine coolant temperature sensor. If you tried to run the car with this unplugged you will flag that code also. Check the mechanical timing. I hope you're not trying to run a fresh motor on new larger injectors. Would be much easier on the stock system with stock injectors get the motor running then make changes

 

[Boostedmm17]

Okay I wasnt clear. Haha
I cleared the codes after I did that and plugged everything back up before I cleared them. Them they come right back.

The motor isn't a rebuild just a different bottom end that has 100k on it. And everything fuel wise is stock. The only thing upgraded is a big 16g and fmic. But wouldn't the idle or anything change if I disconnected the maf and the o2?

 

[pauleyman]

No. Check the mechanical timing and get back with us

 

[Boostedmm17]

I've done that it's right on point.

I believe it's an ECU problem but I wanted to know what you all thought. I have an extra temp sensor and ecu. But like I said I thought I'd ask you all. Because I've seen one post about the same thing happened and it was the ECU. But that was the only post about anything like that.

http://www.dsmtuners.com/threads/p0100-p0105-p0110-p0115-cels-resolved-look.308087/

 

[pauleyman]

If the car ran prior to engine failure and hasn't been sitting forever I don't see why he would be ecu Why do you suspect ECU what have you done to diagnose that it's ECU

 

[Boostedmm17]

Well it sat since 99 in a field BC the previous owner never changed the oil and had rod nock. And like I said as soon as I clear the codes they come back all together instantly. I checked all the grounds and there good.I'm gonna go back today and take my ECU and temp sensor and see if anything changes.

Oh my friend just reminded me when we first started the car it idled perfect. Then it wouldn't do it again. I'm also gonna take the safc completely off.

 

[pauleyman]

If a car has sat forever id look at the harness and make sure something didn't chew it.

 

[Boostedmm17]

So we put a different ecu in and it started right up idles at 750rpm and runs smooth. But we put the original ECU in my car and it ran fine too. So I have no clue. Haha I believe there is a short in the harness so we're gonna take it out and tuck it ECt. Thanks for the suggestions!

 

[Vegas Smith]

Probably loose wires in the harness plugs.