I have a 2003 Escalade that I have maintained since day 1. Occasionally when driving the car it will say system disability and reduced engine power, which drops the speed to 20 and I can give all the gas I want it will not go. Happening on and off for 5 months. I can shut it on and off a couple times and it will go back to normal. Have taken it in a couple times to dealer and they have drove it and drove it and it behaves. They believe it is the Throttle body and sensor. But for the price of it, just replace the fuel pump 2 weeks ago, they suggest to see it happening to give me a 100% diagnosis. For now they believe it is that. Should I fix it or wait till it happens and slowly putt into the dealership
This is a somewhat common problem on these vehicles, It’s going into “limp mode” Might be as simple as a bad wiring connection at the throttle body. There is a TSB on this from what I can find on google.
TPS malfunction,P2135, reduced engine power!
2003-2006 Cadillac Escalade
2003-2006 Chevrolet Avalanche, Corvette, Express, Monte Carlo, Silverado, SSR, Suburban, Tahoe, Trailblazer
2003-2006 GMC Envoy, Savana, Sierra, Yukon
2003-2006 Hummer H2
2005-2006 Pontiac GTO
Equipped with a 4.8 5.3 6.0 or 7.0 V-8 Engine
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
A vehicle may be brought into the dealer for a reduced power message, and DTCs P0120, P0220, P1516, P2101, or P2135.
The Throttle Actuator Control (TAC) / throttle body type trouble codes, may be caused by a loose wiring crimp at the throttle body connector, or a broken throttle body circuit.
Complete the current SI diagnostics for any symptoms or trouble codes found. If a intermittent T/P or TAC module type code is occurring complete the inspections below.
Inspect all related throttle body terminals for a loose wiring crimp. The loose crimp may be difficult to find, and the poor connection will be between the terminal and the copper strands of the wire. Wiggle test the individual throttle body circuits to see if the concern can be duplicated.
Inspect the related circuits for broken wires inside the insulation. The outer wire insulation may look fine, but the internal copper strands may be partially broken. Breaks in the wires usually occur within 1 to 4 inches of the throttle body connector. Wiggle testing may also induce a trouble code to set.
On C/K trucks complete SI procedures for voltage drop on grounds G103 and G104. Grounds G103 or G104 may be loose or corroded.
If a terminal crimp or a broken wire has been found, repair or replace only the circuits involved. There is a throttle body pigtail connector available through GMSPO, but installing this pigtail connector may cause other intermittent TAC module/TP codes at a later date. If this pigtail must be used, please follow the SI procedures for Splicing Copper Wire Using Splice Sleeves. (the proper Kent-Moore crimping tool must be used for this repair)
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
And the dealer should have been well aware of this… especially after reading the stored fault codes… which he should have done.
I urge you to print this thread and bring it to an independently owned and operated shop for a look-see. You are getting what has become increasingly common treatment from dealers for drivers of older vehicles… complacency and disinterest at highly elevated hourly rates.
Too bad it’s not a 1985 model DeVille. I would tell you to change the $100 PCM (computer). Not saying it’s not the computer but nobody would replace one on an 03 on my office chair non-diagnosis. I wish the dealer people had more success with this kind of problem. Then they might act like they had a clue. I hope one of the offered clues helps and I hope they’re good reading because I’m going to read one or two.
Just read the description of problem and possible solutions. No wonder I am not interested in working under the hood. Can barely work there anyway.
thank you for your input.