Chevy Tahoe Dies Then Starts Right Back Up

Question:
ENGINE STALL AT DIFFERENT SPEEDS. WILL START RIGHT UP. HAVE TRIED TO SEE IF ANY CODES AND THE EQUIPMENT COMES BACK WITH NONE. FIRESTONE STOCKTON CA HAS TROUBLE SHOT AND CANNOT FIND ANY PROBLEM. HAVE CHANGE THE ABOVE PARTS AND HAD THE ALT BENCH TESTED AND IT CHECK GOOD. HOWEVER WHEN I DISCONNECT THE POSITIVE WIRE ON THE BATTERY THE ENG DIES. PLEASE HELP. 1997 CHEVY TAHOE. 5.7L. Changed THE FOLLOWING: COIL, Ignition module and SPARK PLUGS, WIRES. TOOK IT TO FIRESTONE AND THEY COULD NOT FIND ANY THING WRONG.

Answer:
Thank you for tip/donation. Intermittent stalling problems are one of the most difficult things to diagnose. Without any trouble codes to go on makes it even more difficult. A fairly common problem on these trucks is a faulty ignition switch, especially if the truck just shuts off. The switch distributes power to many of the electrical systems. They can cause this condition of a stall and re-start ok. One way to check that is to have the lower steering column cover removed to gain access to the switch.


Tapping on the switch, or pulling on the harness at the switch AND the other end of the harness under the dash while the truck is running will usually cause a faulty switch/harness to act up. Fuel pump going bad is also a common problem, but they will usually cause the truck to chug a little before stall, hard to re-start, and also A.M. Starting problems.

Have also had a problem with a ground wire causing electrical problems on the rear top portion of the passenger side cylinder head. All grounds should be checked.

Does not sound like a battery or alternator because it starts right up. Removing the cable is not really a good test of the charge system on todays vehicles as it used to be. Although you should have the battery cable checked and wiggled to see if possible poor connection.

I will attach a picture of ignition switch/harness that may be helpful to you or your mechanic. That should be the area to concentrate on. Thanks again for tip/donation. I will send a pic. To help you/your mechanic.

Question:
2002 Chevy Tahoe truck won't start. Engine cranks but will not turn over... Checked airflow, spark plugs, and fuel pump. Any suggestions?

Answer:
Well, there are too many things to list. Does it have spark on all cylinders, does it have injector pulse on all cylinders, does it have at LEAST 55 psi. Fuel pressure, is the security light on, any stored trouble codes, is it cranking fast enough, How/when did it stop running, etc. You need to take it to a shop and get the diagnosis started. No magic answer with a general 'no start' condition. Need much more info. To help with this one.

Question:
I have a 2004 Tahoe and just lost power brakes and power steering simultaneously. I first suspected a belt failed, but now I'm thinking the same pump powers the power steering and the power brakes booster. Does this sound right, and if so, what am I looking at for repair costs, time. I was planning on traveling out of state tomorrow afternoon, but am now doubting that I'll be able to.

Answer:
Most likely this is a problem with the power steering system. The power steering pump supplies pressure to the power brake booster. This is like a vacuum controlled booster on most other cars, but instead of vacuum, it uses power steering pump pressure. If steering fluid is ok, then the pump has probably failed. Most of the time the shaft that connects the pump pulley to the internal parts of the pump snaps.

The pulley will turn with the belt, but the internals of the pump do not pump pressure. Without having a pressure testing kit, you can put a large screw driver between the pump pulley and the pump itself, and see if you can pry / push the pulley forward (toward the front of the truck)

If it moves more then 1/8 inch, the shaft has snapped and the pump needs to be replaced. Cost fro repairs varies depending on where you would get the repairs. At a GM dealer, expect to pay approx. $300 for the pump, plus 2.5 hours labor. At another repair facility, the pump would cost approx. $125 for a non-factory pump, labor time the same.


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