20 Most Recent 2002 GMC Envoy XL - Page 5 Questions & Answers

low on freeon

Check to see if the belt(s) are properly tightened. May have loosened up after the alternator changed.

Or, the P/S pump is failing. The grinding could be the bearings inside the P/S pump.

If the problem was not there before the Alternator was done, I would take it back, and ask.

sounds like the power steering pump is faulty. Take it to your mechanic.

check the bulbs, check the connector ,check ground and voltage power check fuses and check brake light switch right above the brake padal.

SOUND LIKE FUEL PUMP PRESSURE VERY LOW OR STOPPED UP FUEL FILTER.

Usually $2.00-5.00 for each spark plug. Anywhere from $50.00-75.00 for spark plug wires. A fuel filter is usally around $10-20. Around $100 or so, labor for all.

The engine coolant temperature sensor(ect)is located
on the front of the engine, just above the alternator.
Hope this helps.

A heater core is like a small radiator,its likely your heating system is picking up the slack from a clogged radiator, your radiator is probably in need of replacement.

on the left front of the block by the alt. 4.2 L engine

wheel bearing bad

It means the car has not reached operating temp. The computer wants the engine a certain temp so it can go into "closed loop" where it fine tunes the fuel mix for optimum economy and emissions. If it cannot reach that temp it sets that code. You either have a low coolant level or a stuck open/missing thermostat.

this is consistant with the wear indicators on the brake pads. have the brakes inspected and dont fall for replacing calipers and all the other garbage they try to sell. go with ac delco pads and machine the rotors on the vehicle. happy holidays

P0136 - O2 sensor malfunction, Bank 1 sensor 2." Drivers side exhaust down pipe after the Catalytic converter O2 sensor needs to be replaced."

P0606 - Control Module Internal Performance " Internal PCM failure." Replace the PCM.
For Electronic Throttle Control applications, an internal PCM failure, or an ETC system FMEM condition exists. Repairing the other DTCs can fix the P0606.

Good luck and hope this helps, keep me posted. Be glad to know you got your GMC running 100% again.

Check and make sure your radiator cooling fans come on. If you turn on the airconditioning the fans should come on. If they dont come on with A/C then check the fan relay.
If they come on with the A/C only then replace the Fan Temp Sending Unit. Its usually a brass screw into the intake manifold switch with a few wires pluged into it. Buy the new one first to know what it looks like.

On the brake pedal under dash is a switch that is actuated when pedal is depressed. depress pedal and check that the switch is being depressed. if not the switch can be adjusted by a nut on the neck of the switch. Good luck!

release the traction control if equipt.check to see if the trac control notification light comes on.if not i would check the transmission or have a trusted mechanic look at it.REMEMBER you dont always have to have a transmission rebuilt sometimes its just a clogged filter.

posted for another similar question I aswered:
There is usally and idler wheel that the fan belt goes around that you have to push away from the belt with a socket wrench or a special tool you can buy at most auto stores (a long bar with the proper drive on the end of it) it inserts usaully dead center of the idler. Sometimes I just use a crow bar pressing againt the idler pulley if there is something safe to press agaist. Sometime you have to losen the alternator bolts and tip the alternator away from the belt if it runs of the same belt as the fan.

They make a tool set that has a wrench and holding tool. Otherwise the best way is to take a long bar with a point on the end, place the point on the flat part of the top of the hex nut flange towards your left and hit the other end of the bar with a large hammer. the jarring should break it free.(If you have a compressor an air chisel works great for this)

The fuse sometimes located by rear controls or could be switch faulty..Double check that!