Archive for the 'Chevrolet' Category

My 2005 Chevy Silverado AC Cutting Off Above 20MPH

Justin’s question:

My 2005 Silverado is driving me nuts in this heat. The ac blows great, until I get over twenty miles an hour, then it shuts right off. It could sit all day idling, and be cold as ice. But once I drive over twenty, wham, it stops blowing cold air. HELP!”


I’ve seen that happen before. They’ve had nothing but problems with the control heads for the AC and Heating system on those trucks. The one I fixed just needed a new control head, and they had plenty for sale at the dealer (since they break down so much.) Somehow the computer circuits inside the control head just break down a lot and then just turn the AC off. They can break at any time, but I have seen them cut off at certain speeds only in those trucks, which seems pretty weird but what do you expect with computers?

Putting big wheels and tires on my 2005 Impala

Jeremy’s question:

I’m thinking about putting big wheels and tires on my 2005 Impala. As a professional mechanic, do you see any downsides in doing this?”


Yes, I don’t ever advise anyone to do this. Your Impala was computer designed for the rims and tires that it came with. The suspension system rides best with those size tires. The braking system works best with them. AND the gas mileage will be best using those rims and tires. Putting on Huge rims and tires may look cool, BUT it will adversely effect handling, braking, and gas mileage. If you want fancier looking rims, go right ahead, but I wouldn’t change their size.

2002 Chevy Malibu Reprogram New Key

Landy’s question:

My 2002 Malibu had the key stuck in the ignition and it wouldn’t turn. So I put in a new ignition tumbler and key. The car started, then died. Now it won’t start and the theft system is flashing. What can I do to get it back starting again?


Try to start the car, then release the key. The Theft System light will blink. Then just leave the car for about fifteen minutes. Then turn the key off for 10 seconds. Then restart the engine and it should work. This is just how you reprogram it to work with the new key and tumbler.

2003 Silverado makes a clunking noise

Michelle’s question:

My 2003 Silverado makes a clunking noise coming from the rear end when I take off harshly. I’ve had that spline greased where the drive shaft fits into the transfer case, but the noise came back a few days later. Is there anyway to permanently fix this?”


Yes, there is. GM offers a nickel plated front yoke that won’t clunk. I’ve changed a few out and they stopped clunking for good. So if you want the noise to go away, buy that fancy nickel plated yoke from GM.

2006 Chevy Colorado #5 Cylinder Misfire

Wendell’s question:

My 2006 Chevy Colorado is running a bit poorly. The check engine light came on with # 5 misfire. I had the spark plugs changed and even the coil on number five, but it’s still the same. HELP.”


Yes, they’ve had some problems with the valves not seating correctly on those Colorados. Hopefully you don’t have too many miles on yours to put it out of warranty. If you’re under warranty still, just take it to the Chevy dealer. They will probably have to repair the engine for free because to fix the valve seat the heads have to be pulled on the engine. It’s a big job, but it would be under warranty as long as you don’t have too many miles on it.

99 chevy metro screeching belt noise when running

Margarito’s question:

i have a 99 Chevy Metro. every morning that i turn it on it makes an awful screeching noise and also it blows out a cloud of white smoke. one person told me that my belt might be to tight and another said its not tight enough. what can i do about the noise and the smoke?”


I assume the smoke is coming from under the hood and not out the tailpipe. If it’s coming out the tailpipe, then the head gasket in the engine is blowing and it will cost a ton to fix. If the smoke is coming from under the hood, then it’s a fan belt. It’s probably not the belt itself, but whatever it drives is probably wearing out. Such as a worn water pump or alternator or AC compressor which will lock up and then smoke the belt. Have everything that’s belt driven checked out to find out which one is wearing out before you get stranded.

98 Chevy Blazer A/C Alternates Hot Cold

Jerome’s question:

My 98 Blazer is driving me nuts. When I turn on the AC, it keeps fluctuating between hot and cold air blowing out. No matter what I do with the controls, it just goes Hot, Cold, Hot, Cold unless I just turn the whole thing off. HELP ME, please.”


Well, today’s your lucky day. I just fixed a Blazer with the same exact problem last week. There’s a part on your heating and ac control system called the “temperature blend door actuator” and it probably has gone bad. When this actuator breaks down, it keeps opening and closing the blend door, so you get hot air when it’s open, and cold air when it’s closed. If you’re mechanically inclined, just go to a Chevy dealer and buy the actuator (they can show you on their computer where the little monster is hidden in the dash.) Or, have a mechanic change it out for you.

My 1999 Chevrolet Z71 Pickup (1500) won’t disengage from 4X4 when I use it

Adrian’s question:

My 1999 Chevrolet Z71 Pickup (1500) won’t disengage from 4X4 when I use it.”


THE two most common problems are a bad switch that engages the four wheel drive, or a bad motor on the transfer case that the switch sends power to engage the four wheel drive. The motors do fail a lot in those chevys as they age, so I’d check that out first. Good Luck,

2001 Chevy Venture temperature gauge acts wildly

Joshua’s question:

” I want your professional advice. The temperature gauge on my 2001 Chevy Venture acts wildly. It goes from half to three quarters to even higher. But I don’t lose any coolant and it runs fine otherwise. I even had the dash unit replaced with a GM rebuilt unit and the temperature sending unit on the engine changed also. BUT, it still does the same thing. What should I do now?”


Well, make absolutely sure you’re not losing coolant and that the head gasket on the engine isn’t starting to blow, but I assume the other mechanic has already checked this stuff out. If so, I’d personally live with it. I’ve seen many of those Ventures just act that way. Something in the dash unit and the software just does that in many of them as they age. I have personal customers who’ve lived with those “nutty” gauges for years, and it gets REALLY hot here in Texas. They’ve had no cooling system problems otherwise, so they just live with it.

1998 Chevy Malibu makes a clunk when I go over larger bumps.

Oliver’s question:

” My 1998 Chevy Malibu makes a clunk when I go over larger bumps. A shop changed out the strut mounts, the torsion bar bushings, and the front struts. But the clunk is still there. I took it back and they said nothing was loose now. Have you ever seen this before?”


Well, as a matter of fact, I was stung by this very same problem last year. It turned out that the outer tie rods were making the clunking noise–even though they had no play in them when pulled on, and physically looked perfectly OK. It’s a rare one, but it happenned to a Malibu I was working on, and it took me a while to figure that out. As tie rod ends are pretty inexpensive, you might try that next.