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Another MAf question

Cool Zr2

By Cool Zr2
in Ask A GM Technician

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Cool Zr2 Enthusiast

Cool Zr2

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I found that the circut/fuse that the MAF/O2/cmp/etc runs on was blown. So I put another fuse in there and it popped right away, and another, and another.

 

Any ideas? The maf isn't bad because I tested it on a diferent truck.

 

EDIT: I unplugged the O2 wiring harness near the PCM and the fuse popping went away and my normal drivability is mostly back.

 

Now that I have narrowed it down to the area of the problem, would you assume that it was a sensor or an exposed wire? I just got all dude-ed up to go to work so I won't get to it untill thursday when I get home...... But I will be checking your reply at the motel on my palm.

GM-Tech Senior Enthusiast

GM-Tech

Posted
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No ideas. I assume it pops the fuse even if you have the MAF disconnected? If so, then you just need to trace that wire back and find out where it's grounded.

Cool Zr2 Enthusiast

Cool Zr2

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EDIT: I unplugged the O2 wiring harness near the PCM and the fuse popping went away and my normal drivability is mostly back.

 

Now that I have narrowed it down to the area of the problem, would you assume that it was a sensor or an exposed wire? I just got all dude-ed up to go to work so I won't get to it untill thursday when I get home...... But I will be checking your reply at the motel on my palm.

 

 

 

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted

Ummmm, what schematic should I be looking at? I know you have kind of a mix there, so I'm not sure if I should be looking at a schematic for your model/year truck or some full-sized with a V8.

Cool Zr2 Enthusiast

Cool Zr2

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Ummmm, what schematic should I be looking at?  I know you have kind of a mix there, so I'm not sure if I should be looking at a schematic for your model/year truck or some full-sized with a V8.

 

 

 

The truck is wired as it was when GM built it, the only exception is the v-8 FI plug that connects to the top of the intake, the 4.3 one was removed and the V-8 one was installed in its place the the additional wires were installed in the proper pins in the PCM harness. So yes, it is the stock 97 4.3 O2 wiring. I'll be home tomorrow night to get a look at it, I'm assuming that a wire got exposed and is shorting out, probably the positive feed for the O2 heaters.

Cool Zr2 Enthusiast

Cool Zr2

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Found it, the wires on the driver side post cat (B1S2) were laying on the Bank 2 pipe, so they melted and were shorting out. I found this after I chipped away a ton of iorn ore mud that was holding it down from that sweet mud hole I went through.

 

Here is the hole that caused all my wonderful problems, that thick heavy mud is for the birds.

 

DSCF0070.JPG

 

I was the only s-10 to make it through the entire length, most went on the later 1/2 cuz it wasn't as deep.

 

Here is a blazer that got really stuck.

 

DSC01422.JPG

 

DSC01423.JPG

 

Here is a video of the mud hole, my appearance at time stamp 2:35

 

http://www.chevihemi.com/zr2/movies/gilbert43005.wmv

 

"right click and save as"

Cool Zr2 Enthusiast

Cool Zr2

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Tell me about it. Here is a list of what that single pass did to my truck.

 

1. Ripped out the fender skirts

2. Caused the O2 sensor wires to short out.

3. Filled about 1/2 of my frame with mud, that took me hours to flush out.

4. bent up my bumper.

5. Broke the bumper corners.

6. Cracked the air dam.

7. Pissed the little woman off so much she was closed for business for about a month. My favorite color deffinatley isn't blue anymore..... I prefer pink much more.

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