Archive for the 'Chevrolet' Category
Jeff’s question:
“Hi, I have a 2005 Chevy Malibu 6cyl 3.5 4A. my car’s low fuel light came on yesterday. i filled the tank with #87 gas and before i could get out of the parking lot the fuel light came on and the needle went back down to empty. the needle was up to the full mark. also the fuel range low came up and flashed back and forth between the words fuel range 446 miles (which is what it usually says when it is full). a little down the road the engine light came on and stayed on – it is yellow. i checked the cap to make sure it was on tightly. please advise, thanks!”
Answer:
It has nothing to do with the cap. Either the sending unit inside the gas tank has broken, OR you have a computer programming problem. Some of those Malibus need the main computer reprogrammed because their software is incorrect and it can cause the gas metering to go haywire. That is just a simple plug in software fix. So check with the Chevy dealer, give them you VIN number, and if they say there’s a software fix, get that done. If not, you’re looking at a pretty big expense repairing the gauge system, as the gas tank needs to be removed to access the parts and check them.
Doug’s question:
“I have a 94 Chevy 1500 pickup. not too long ago, i started hearing a “thump thump thump” noise when I start the vehicle, and shut it off. it lasts for about 10 to 15 seconds, it comes from under the passenger side of the dashboard. i do know it has to do with the heating/cooling. i just recharged my a/c system yesterday, and now it happens as well, when i hit the recirc button for my a/c i guess that’s the same as a Max button.”
Answer:
OK, since it happens when you hit the recirc button, then it’s got to be the flap that goes from the open (outside air) position to the closed (inside air) position. The flap is opened and closed by an electronically activated vacuum motor that has a rod connected to the door flap. Check to make sure you don’t have any vacuum leaks in the system, as weak vacuum pressure can make it flap open and closed–BUT when the vacuum pressure builds up as the engine runs and sucks more, then the thumping will stop. I’ve seen that happen MANY times. It’s a real BEAR taking that dash apart, so if it works fine after a few seconds, I’d personally just live with it. BUT, if it’s driving you nuts, hopefully you have really tiny hands and arms to fit in there and check things out (otherwise you’ve got to take the whole dash apart on that side to see what’s going on.)
Tal’s question:
My 99 Chevy Suburban acts up when it’s really cold outside, hesitating and stumbling when I try to accelerate. One guy thought it was the coolant temperature sensor telling the computer it was hot when it really was cold. So he changed it out, but it made no difference at all. Help!
Answer:
Well, it was a good guess, but it obviously didn’t fix things. I assume you have no stored trouble codes, because the other mechanic would have told you that. If you don’t have any trouble codes, first have the fuel pump pressure checked when it is really cold outside. I’ve seen the pumps on those Suburbans cut out when they get too cold, and cause stumbling without setting any codes. There is no fuel pressure sensor on that engine, so the computer has no idea what the real fuel pressure is. So if the pressure is low, the computer often can’t set a trouble code because it doesn’t know the pressure is low. I fixed one like that last year and a new fuel pump solved the whole problem.
Latrell‘s question:
My 04 Chevy Silverado with the V6 engine is running poorly and the check engine light came on. It had codes for misfire on cylinders 2 4 and 6. What could it be?
Answer:
Well, realize that all three of those cylinders are on one side of the engine. So it’s something that effects one side of the V6 engine, and not the other. It would have to be something breaking down only on that side of the engine. It could be a vacuum leak on that side of the manifold, a problem in the ignition system on that side, or a fuel problem that exist on that side. BUT, the first thing you should check is the catalytic converter. Because your car has two converters on it–one on the left side and one on the right. If one side goes bad, it will cause misfires only on that side and not the other. I fixed one last week with a bad catalytic converter on the number 2 cylinder side of the engine.
George’s question:
I did a brake job on my 03 Impala a month ago. I put on quality pads and had the front rotors resurfaced at a machine shop. but now the steering is shaking again when I stop from sixty quickly, just like it did before the brake job.
Answer:
Well, modern day brake rotors aren’t what they used to be. Machining many models just shouldn’t be done if you’re hard on brakes. Your Impala is one of those models that I never advise turning the rotors on. The rotors will just rewarp in a short period of time. Your car is showing the classic symptom of warped rotors. I would buy a new set of brake rotors if I were you. And if you don’t want to also replace the pads that you put on a month ago, you can get some heavy sand paper and sand the pads down on a flat surface so they will fit the new rotors (they will be slightly warped from meeting the warped rotors, but it’s only been a month so you could try reusing them with a little sanding.
Henry’s question:
My 2001 Venture will crank, but won’t start up. It has no spark. A shade tree mechanic told me to change the crankshaft position sensor, so I did. But still no spark. The guy told me it had a crankshaft position sensor code, so, did I do something wrong?
Answer:
Well, you should realize that your Venture has two separate crankshaft position sensors (engineers can be strange people, why one won’t suffice is beyond me.) I would advise changing the other crankshaft position sensor out. Any good auto parts store can sell you one and show you on their computer where the little monster is hidden.
john’s question:
Harmonic balancer wobbles a little on my 283 chevy engine. It is a 62-63 year model. Engine runs fine with the exception of the wobble
Answer:
The balancer is either bent, OR the keyway is breaking down on the crankshaft. I’d advise taking the fan belts off, and removing the balancer. Then check to make sure the keyway isn’t damaged (if it is, then fix it with a new key NOW before it breaks off and ruins the crank.) If the keyway is fine, then just replace the pulley with a non worn one.
Gary’s Question: My 98 Suburban is missing badly. The check engine light came on and had the code for number 6 cylinder misfire. so I changed out the spark plugs and wires, but the miss hasn’t gone away. what should i check next?
Answer: OK, misfires can have all kinds of causes as I’ve mentioned many times. BUT, in your case, the two main biggies are injector problems on # 6, or an intake manifold leak on # 6. SO, have the intake manifold checked for vacuum leaks. Those plastic intake manifolds have real problems with leaking as the manifolds and their gaskets often warp over time. If you can’t check this yourself, have someone smoke leak test the manifold, and if it’s leaking, smoke will come out of the hole where the leak is. Let’s hope it’s that, because injector replacement is REALLY expensive on that engine because they’re hidden deep inside the engine and a lot has to be taken apart. Good Luck.
Gretta’s question My 1999 Tahoe keeps setting the ABS warning light. It’s been snowing a lot, and I want the brakes to be working right. What could be causing this?
Chevy Tahoe 1999
Answer: Yes, the ABS braking system is a fail safe system, so that if the ABS portion breaks down it just reverts to normal brakes. BUT, you won’t have anti lock capability when that light comes on. Now they are rather complex computer driven systems, but since you mention you’re in a snow area, that can often be the cause of ABS malfunctions in that Tahoe. The salt and slush can cause corrosion in the ABS wheel sensors. GM even put out a bulletin about this a few years back. So have the wheel sensors removed, the assembly cleaned of debris, and see if that fixes your problem. You may need further work, like replacing bad sensors or broken wiring, BUT start with the simple process of just cleaning the sensors and their mountings off. Because that often fixes ABS problems in those Tahoes.
