2001 HD 8.1 Problem
 

I've got a 2001 Hd with the 8.1, Allison tranny, and 4:10 gears just turned 160k with no major problems. When i'm on a long drive with the truck (over an hour or so) it starts to sputter and want to shut off, I have to mash the gas to get the truck to respond and once it gets back to speed it starts doing it again. Last time it did it for 40 miles till I got home, shut the truck off and the next morning it was fine. The check engine light doesnt come on but the ABS and E brake lights have not neccessarily whent he truck is acting up. I have a supretech tuner for it, but the truck was doing it before I got the tuner and the only code the tuner reads is the engine torgue signal circuit which is a tranny code. Any heads up would be much appreciated before I sink a fortune into a mechanic. The last one I took it to, the truck never did it for him because he never drove it for over 30 mins.

Re: 2001 HD 8.1 Problem
 

:welcome2: to the site! When is the last time the fuel filter was changed?

Re: 2001 HD 8.1 Problem
 

The ABS and E brake lights coming on are usually due to a bad ground - at least this is a common problem in the S10s of these years - clean the ground on the core and it goes away.

I'm thinking that the transmission could be causing the issue, especially if you are getting a tranny code. Almost sounds like a torque convertor issue...

Also, have you ever replaced the crank position sensor on it? They are notorious for failing on 2001s and 2002s.

Re: 2001 HD 8.1 Problem
 

The tranny code is p10781 engine torgue signal circuit, only shows up occasionally. I just put an exhaust on it and and removed teh catalytic converters. The 02 sensors that are normally behind the cats were plugged off I'm assuming by the factory cuz I've never done it. I thought the converters were causing my problem but removing them and putting in a magnaflow exhaust hasnt helped it. Is this condition similar to what happens with bad crank or cam sensors?

Re: 2001 HD 8.1 Problem
 

Your code has to many digits,

Re: 2001 HD 8.1 Problem
 

It's P1781,

Re: 2001 HD 8.1 Problem
 

I would investigate that code some more, The Allison TCM/wiring can cause drivability problems, Fuel system problems can also set this code.

Vehicle Application: 2001 Chevrolet Silverado 2500 HD 8.1L, GAS, Vin G

Customer Concern: Very intermittent loss of power. OK at this time. Electronic Control Module (ECM) codes: P1571, P1781, P0700.

Tests/Procedures:

1. Check for Transmission Control Module (TCM) codes.

2. Check the condition of the requested torque signal wire, Orange/Black, circuit #463, between the ECM, pin 13 of the blue connector and TCM, pin 22 of the gray connector.

3. If the wire checks OK, try updating the ECM calibration per bulletin #01-06-04-020.

4. Monitor the fuel pressure while driving.

5. Clean the MAF sensor and fuel injectors.

Potential Causes: Miscalibrated Electronic Control Module (ECM)
Fuel Injector(s)
Fuel Pump
Mass Air Flow (MAF) Sensor
Transmission Control Module (TCM)
Transmission Control Module (TCM) Wiring