1997 Chevy k1500

[Schurkey]

Yup. I don't understand that AT ALL. But then, I don't understand why your scan tool is showing three short term fuel trims, with two of 'em being "0", either.


Any chance someone put a defeat device on the O2 sensor harness from the vehicle, to mimic O2 sensors? Or are the vehicle harnesses for the sensors open with nothing plugged into them?

 

[Obs89]

Yup. I don't understand that AT ALL. But then, I don't understand why your scan tool is showing three short term fuel trims, with two of 'em being "0", either.


Any chance someone put a defeat device on the O2 sensor harness from the vehicle, to mimic O2 sensors? Or are the vehicle harnesses for the sensors open with nothing plugged into them?

That’s what I’m thinking. But I think mu
Problem is a leaking spider or regulated. And a bad fuel pump. But also the coil has never been changed either

 

[Obs89]

Yup. I don't understand that AT ALL. But then, I don't understand why your scan tool is showing three short term fuel trims, with two of 'em being "0", either.


Any chance someone put a defeat device on the O2 sensor harness from the vehicle, to mimic O2 sensors? Or are the vehicle harnesses for the sensors open with nothing plugged into them?

That’s what I’m thinking. But I did take apart my upper intake a min ago and checked every injector to see if they were leaking and they aren’t. Also I believe the truck runs fine with low pressure because it has the upgraded spider injectors I noticed that today when I took them apart. Also checked the regulator to see if it was leaking it wasn’t. So maybe it’s a sensor or the coil that’s bad because I haven’t changed that yet.

 

[Obs89]

I put a new fuel pump in and pressure is better around 55 and like 50 at idle I think I will double check Tommorow. Also I got a new cap and rotor from Amazon and will arrive tmo I’m going to put it on aswell. And if non of these work I will swap the pcm over. I have a pic of how much gas was coming out the exshaust and also it was spitting gas out around the header where exhaust valve is. I’m not sure if this is a leaking gas problem or just dead cylinder that’s not firing and just shooting gas everywhere

You must be registered for see images attach

 

[Obs89]

New cap/roter on. And only cylinders that are missing now and are counting is 6 and 3 I noticed when I plugged a new spark plug in it stopped missing for a min then started back. I assume it got gassed up and failed. My only assumption left if leaking reg or spider injector. Even tho it has the upgraded spider injector in it.

 

[Obs89]

Dead thread but hate seeing people leave them with no answer. my problem seemed to be a stuck open injector. Caused a wire in the harness by the brake booster coming from the spider injector i still have yet to find which on it is . i can just go shake it and it will go away. so i think i will looke into it when i do 0411 swap

 

[OBS_Trash]

Dead thread but hate seeing people leave them with no answer. my problem seemed to be a stuck open injector. Caused a wire in the harness by the brake booster coming from the spider injector i still have yet to find which on it is . i can just go shake it and it will go away. so i think i will looke into it when i do 0411 swap

I read each comment because I’m in similar shoes. Truck is running rich, I’ve got a P0102 and P0151.

I’m starting over after launching a parts cannon since the mech shop couldn’t figure it out. Wishing I would have read more threads. But my truck has 330,000 miles so replacing parts isn’t a bad feeling knowing she probably could use fresh parts. But at the same time I just want her to run good. I’m not the most knowledgeable at electrical troubleshooting so that’s where I’m at. That’s the learning part of this for me. Good luck man, keep posting an update if you figure it out!

 

[Obs89]

I found my problem it was the harness I beleive. grounding cause it fell on egr exhaust line. I zip tied it up and haven’t had problems since I will keep u updated. But I noticed mine by turning key one and seeing the injector stuck open shooting with just key on engine off

 

[Obs89]

Temp sensor and maf helped alot aswell.

 

[Sean Buick 76]

Still no 02 sensors???