Getting Ticked Off At My S10!!! - inconsistent idle

[nubuilder]

Well, after 300+ miles, this is the only error code. Can anyone tell me exactly which O2 sensor this is (I have 3 of them)?
P0144 = O2 circuit high voltage bank 1, sensor 3

I've ordered an EGR block-off plate (for $12 its worth a shot VS $100 for a new EGR). Once I install this, what will the ECM do if I completely remove the EGR valve? Will my MPG's drop? Or do I need to leave it plugged in and tied up somewhere?

 

[Bigredmariner]

Bank one is driver side, sensor 3 should be the last one on that side or post cat. Not 100% sure of your setup but that should give you some info to go on.

 

[nubuilder]

Bank one is driver side, sensor 3 should be the last one on that side or post cat. Not 100% sure of your setup but that should give you some info to go on.

Thanks Jarrod!

Actually, there's 3 of them. From what I've read, 2 are pre-cat and 1 post-cat.....so I'm guessing that this means that the one behind the cat is bad. Does the post-cat one really do anything? I thought the pre-cat ones monitored how much emissions the engine was putting out.

 

[Bigredmariner]

I would think that the rear one is just there to monitor the cat itself and see if it's getting the job done. At least on my V8 that's the only purpose for the rear O2's. They have no effect on the engine tuning at all, only to trigger the light. But it could be different with yours.

So yes since you only have 3, that rear most O2 should be bank1 sensor3.

 

[drperry]

The O2 sensor after the cat, is the same, all it does is tell you if your cat is working...

I'd look into getting a tune so the computer doesn't look for the EGR...

 

[nubuilder]

I decided to dig this up since I've never found a real answer to this problem searching Google.


I need to recap a little:
I've replaced the TPS and IAC with no changes to the idle. I also unplugged the EGR (it is still bolted on and sitting there).

Last week I finally went to the junkyard and picked up a '97 S10 ECM (was from a vehicle with 3.42 gears; my speedometer was off by 3mph at 60). Anyways, drove around for almost a week with that and the truck seemed to idle down and hold back much better. I got tired of the speedo and mileage being off so I put my original ECM back in. The problem came back, but not quite as bad (or so it seemed).


Just this last Friday I had a new fuel filter put on. Since then, I've driven 130mi. Now the truck doesn't rev up to 2,000rpm on startup; more like 1,500rpm. It also seems to be idling down better. It still sometimes doesn't idle down/hold back right away, but it eventually does so quicker than before. However, according to my fuel gauge, my MPG's have dropped (I'm currently at 1/2 tank with 130mi; usually I'm at 200mi this time of year). I'm hoping that my fuel filter isn't leaking, or else maybe the ECM is recalibrating itself to the increased fuel flow and still learning to slow the pump down. I have no idea. Anyways, I'll know more about my MPG's when I fill up.

Once I do fill up (once or twice), I think I'll plug the EGR back in and see what happens.


I'll keep you guys posted!

 

[CJ Hungus]

You should just sell it to me for a winter vehicle.

 

[nubuilder]

You should just sell it to me for a winter vehicle.

You want it? I'll sell it to you once the snows gone!!

And no, I'm not kidding. I really want the same truck again, just with 4wd.

 

[CJ Hungus]

I will definitely think about it. We'll talk in 6 months.

 

[OldCracker29]

Still don't have this figured out.