20 Most Recent 2002 Chevrolet Tahoe - Page 6 Questions & Answers

Check the wiring and connectors going to the alternator. It appears you have a bad connection or broken wire - that would cause intermittent flashing of the alternator light or a steady glow, depending on how bad it is. Pay special attention to the alternator output wire going to the battery - you may not have a clean, solid connection to the new terminal.

As an aside, a leaking seal around a battery post can cause significant deterioration of the terminal connections in a few days. After several bad experiences, I always apply a counter-torque to the battery terminal with one hand while I tighten the terminal clamp bolt with a wrench in the other hand. The counter-torque keeps the wrench from applying force to the battery post and cracking the seal. Since I started that practice, I've had very little trouble with terminal corrosion.

the switch is out of sink with the leaver needs adjusting.

This is related to communication with the transmission shift "range selector". It is a loose connection that is causing the control module to "see" a park or Neutral and the doors unlock. This may turn on the check engine light also. It may eventuallly cause the transmission to not shift, also. You need to check the connection on the transmission and on the shift range selector (sometimes called the "PRNDL" switch. The computer automatically locks the doors when you select a gear. It is seeing no gear selected and unlocking the doors, the seeing a gear selected again, and locking the doors. You really need to get this repaired soon.

1) Bad/clogged Idle Air Control (IAC) especially if you have a oil and gauss air filter. 2) Air leak in the duct between the air filter and Throttle body. 3) Bad or clogged Mass Airflow Sensor (MAF). 4) Bad Throttle Position Sensor (TPS). If no throttle cable the throttle body assembly..

most of the later model gm cars have a chip on them to prevent theft, but your vehicle should have a fob to unloc and relock the doors, itf that is also not working, you will probably have to pull the door panel and check the linkage. If you push the unlock button on the fob and hear a click, but the door does not unlock, rpeair the linkage. Most of the info can be obtained by purchasing a haynes or chiltons manuel for your year model. These can be purchased at most auto parts dealers.

The common problem here is the high/low switch in the stalk. It's connected with a black and a gray connector. The latter is where you want to start checking with a multimeter. Hang on, there's a great webpage for this... [later] Ok, found it, read this and you should be able to sort it out quickly. How to Test the Low High Beam Headlight Dimmer Switch

Listen carefully when you first turn the key to "ON" (not Start). You should be able to hear the Fuel Pump run for a few seconds and then shut off. If not, you may have a bad fuel pump. Get it to a qualified service technician for this.

This could be a few things. One is bad quality gas but since it started up again that may not be the cause. The other may be the fuel filter, fuel pump, or fuel injectors. Any of them would cause the engine to sputter and shut off. Do you normally buy fuel from this station? Was it a little old "Mom & Pop" station? They sometimes have dirt in their fuel. If not does the station you by from have pure gas, no ethanol. It's getting hard to find fuel that isn't at least "E-10" or 10% ethanol (alcohol). GM vehicles made after '97-'98 will run just fine on E-10. One thing about ethanol is it is basically like a solvent. We use alcohol to clean product before going into a paint process. It breaks down the oils and dirt. This can happen in a gas tank with ethanol. Especially if you have never or almost never used E-10 or higher fuel. Are you sure you didn't happen to buy E-85 fuel? Also, do you normally keep your tank at least half full? Sometimes a gas tank, fuel lines, or fuel injectors will have a varnish like build up and the ethanol will break it down and it will clog up the fuel filter, fuel pump, or fuel injectors. Do you know when the last time your fuel filter was changed? Then again it may be the fuel pump may be weak and/or about to fail. It happens and it can be expensive because the pump is inside the gas tank. I found out not to let the fuel level get super low, too. I let that happen one time while on the road and I almost couldn't get it started. One thing you can do to help extend the life of the pump is when you want to start your Tahoe, first turn the key to the run position without starting the engine. You get a lot of warning sounds for a couple of seconds but if you listen really close you probably can just hear the fuel pump pressurize the lines. It only takes a second and once it is pressurized you can't hear the pump. This will help extend the life of the pump as it doesn't have to work as hard for that short period of time during start. Most people will turn the key from OFF to START in one quick turn. Try to get into this habit for a while. It doesn't cost you anything and if it works it will save you some hassle until something actually completely breaks down. My son has an old BMW and he was complaining about having to put 2 fuel pumps in it in 2 years. I told him to try letting the pump charge the system before starting and he hasn't changed the pump in almost 4 years. Now it's part of the cute quirk of having a 32 year old car.

Have a mechanic check the wiring to the fuel pump and test the fuel pump itself and also test the ECM and COILS

Since this all started after other work was done, I would suspect that work is related. Did you allow your rear brakes to go "metal to metal"? [wore the pads down the the steel backing plates] If so, that powdered steel or iron may have accumulated onto one of the rear wheel speed sensors or the related reluctors. This is a simple but common problem caused by an owner who waits to long to repair his brakes. Solution is to clean the debris off the affected parts.

it is a distinct possibility as some dealers use a E added fuel to rip motorists off. It is also a possibility that there was water in the fuel so I would have the fuel filter changed as a precaution. Run the fault codes to check for reported faults.

run the fault codes and look for a venting problem with the canister.

Might be a bad fuel pump

Maybe because it is not genuine.

try some fuel additive that removes water and cleans injectors