74 '40 Build LM7/NV4500 (1 Viewer)

[h82crash]

Very nice project. Just read thru your thread.

I'm doing something similar with my 74 as well, although with a 4L60e.

Thanks! Good luck with your build.

 

[h82crash]

Okay, the following is pretty boring stuff but, I was having a fit trying to figure out some fault codes. My first GM and I was just going by the basics. Was getting the P0507-Idle RPM higher than expected, and P0135-O2 heater circuit fault Bank 1.

The first one is most likely due to no speed sensor signal to the PCM. It is expecting to be at 650 RPM when the throttle is closed, but while moving and decelerating, it is above that.

P0135 should be the result of a burnt heater filament or bad wiring. I chased this for weeks and sensors and harness checked good. Well, I'm guessing GM PCM logic uses a time value for going into closed loop to guess the heater is working since the heater circuit is separate from the PCM. Anyway, I found an exhaust leak upstream of the O2 and fixed it. No more code. So, to speculate, the extra oxygen in the exhaust caused a low voltage condition on the sensor and it assumed the heater was not working. I could be completely wrong on this, but I don't know and GM code gurus to run it by.

Now that this is behind me, I can move on to spare tire carrier, dash pad repair, and speaker mounting.

 

[h82crash]

Still having codes occasionally pop up. It's disturbing, as I can't find anything wrong.

On a positive note, I did the gas strut mod on the rear hatch and customized my dash pad.
Write-up here: OEM Dash Pad Repair- With Speaker Mounts - https://forum.ih8mud.com/threads/oem-dash-pad-repair-with-speaker-mounts.1324104/

 

[h82crash]

Found a good deal on 5 FJC wheels and finally got some rubber on them. I'd been experiencing what I thought was driveshaft vibration. It was a low pitched hum and very subtle vibration starting at 55 MPH and up. Well, the vibration is gone with the new wheels and tires. 255/75/17, no spacers, perfect fitment.

 

[wimberosa]

SW Colorado. Offhand that looks like the little valley over by Perrins Peak....but everything is brown right now. Where are you located? I'm over on Junction Creek.

 

[h82crash]

SW Colorado. Offhand that looks like the little valley over by Perrins Peak....but everything is brown right now. Where are you located? I'm over on Junction Creek.

I'm at Bellflower Ranch, about 10 miles east of Durango. Took this on my property.

 

[h82crash]

The rear end isn't naked anymore. Silly me, I thought it was going to be a simple bolt on after refinishing the spare carrier. Nope. I had to modify the latch hook bracket to fit as the new sill had the mounting holes too high. The holes were so far off that just enlarging the holes wasn't going to work. I welded up all the holes and added material to the tops of the ears. Then drilled holes in the locations that would work. Powder coated and done.

 

[rickpaw]

The rear end isn't naked anymore. Silly me, I thought it was going to be a simple bolt on after refinishing the spare carrier. Nope. I had to modify the latch hook bracket to fit as the new sill had the mounting holes too high. The holes were so far off that just enlarging the holes wasn't going to work. I welded up all the holes and added material to the tops of the ears. Then drilled holes in the locations that would work. Powder coated and done.

Yup, I've had to do that to my latch as well. So I'm not the only one with that issue, it appears.

 

[h82crash]

Better.

 

[h82crash]

I took this before winter.