Please help me! All kinds of problems!

[devin_deville]

Ok. Here i go. This is gonna be long as hell.
First off, i drive a 2006 Gmc Sierra 1500 with a 4L60E Tranny. Its a 4wd z71 crew cab. I have a 4 inch Superlift. 33" Mickey thompson baja MTZ's on 18's.
Nelson Performance Tune, No Torque Management, 91 Octane.

It has given me nothing but problems.

First problem.

Fuel Trim Rich Bank 1 & 2 AKA DTC's P0172 & P0175

I use the Genysis Scan Tool, and i hooked it up and ran a few tests to try to narrow down the cause of this. In closed loop the long term fuel trim data reads 20%.

I've checked all 4 Ho2 sensors, all are functioning within the 200-800 mV range.

I have physically inspected all EVAP lines for damage or blockage, all are fine.

I have checked the inlet screen of my MAF sensor for blockage, Fine.

Objects Blocking the throttle body, Fine.

Cleaned my air filter, Fine.

Checked all injectors, and the fuel pressure regulator, Fine.

I have done everything in my power to find the problem but everything seems to be fine. I get about 11 mpg on a good day, and that's nothing compared to what it used to be before i put the Nelson PCM in it.

Second Problem.

When i am driving down the road, cruising at about the 50-60 mph range, the whole truck will shake violently, and there is a hellacious grinding noise coming from either the middle or the front end of the truck. If anybody could diagnose this it would be greatly appreciated.

Third Problem.

While messing around under the truck on a creeper the other day, i noticed two identical marks on the differential side of the driveshaft, on the northwest side of the driveshaft there is a huge gash, and on the southwest side of the driveshaft there is a huge gash. I have no idea where these are coming from, so if anybody could help with this it would be appreciated.



I am very plagued with problems, and i posted this for help. If anybody can help with any of these problems, please reply. I will literally try anything to get my truck fixed.

Thanks,
Devin Deville

[RedHeartbeat]

sounds like you're running out of fuel. Might be time to replace the pump or filter in the tank. You could have got a bad tank of gas full of water.

[devin_deville]

ok thanks i will look into that. can you help with any of the other problems? the second one scares the crap outta me

[RedHeartbeat]

check the fluids in your diffs.

[devin_deville]

I changed the fluid in the diffs already im beginning to think that its the transfer case.

[RedHeartbeat]

I had one go dry before and it rattled like crap because it was burned up completely

[foggy]

I've had a transfer case go bad on me, the grinding noise it made was Loud.
Check front wheel bearings also.
Can you post a pic of the marks on your driveshaft?

[Madd Maxx]

For problem 1, try cleaning the MAF wires. There's a special cleaner for this that you can pick up at any auto store. Just spray it on and let it evaporate. Do it twice. Don't touch the wires.

Also, if you haven't done so already, clean the throttle body. Take it off and do a thorough job. It's an easy fix for erratic idle and slow speed surging. And while the TB is off, clean the EGR tube.

[devin_deville]

Thanks guys, yeah i can post pics of the marks on the driveshaft foggy, it'll be tommorrow tho.

p.s. I know the 4L60E is a weak trans, but do you think it will be able to hold up to the power? all thats done to it right now is k&n true dual exhaust, with just converters and a nelson tune, but i am looking to put a sts turbo on it. Ok screw the tranny, with all that boost, you think the little 5.3 can handle it?

[foggy]

I'm running a 5.3 and Flt 4l65e with 10# of boost.