2004 Mazda 6 PCV Valve Noise

Irene’s question:

My 2004 Mazda 6 is making a strange whistling and hooting sound coming from the front of the car. It runs fine, but the noise is a bit too much. Have you seen this?”

Answer:

Yes, I have seen that. There’s a pollution valve on the engine called the PCV valve. It has a hose that connects to one end of the valve which has vacuum pressure from the intake manifold. This hose is rather cheaply made and they often collapses, making strange hooting and whistling sounds. It’s pretty hard to access this hose without removing the intake manifold (which is pretty expensive.) But I’ve done it without taking the manifold off. I just used a bit of elbow grease, some long curved needle nosed pliars, and a bit of selective cursing to get it done.

1987 bmw e30 325i cabriolet Fuse 9 keeps blowing

KHALID’s question:

“Hey mate, i am in need for your expert advice. I drive a 1987 bmw e30 325i cabriolet. The other day out of no where i realize that suddenly my car heater, main headlight beam, obc computer & reverse light stopped working and smoke started to come out from under the glove box. When i opened the bonnet, i see that a fuse (fuse no 9) has melted. i tried replacing the fuse by everytime it blows. Now even my stereo’s playing with me, it come on and off, on and off and its continuous. I tried opening the glove box and stereo to see if there are any burned wires or loose connections but everything seems fine. PLEASE HELP MATE.”

Answer:

Well, something made that smoke unless you’ve got mice with cigarettes hiding in there. So,since you know the number nine fuse keeps blowing, start there. Many guys will just install a jumper wire in place of the fuse for a few seconds. Then see what is getting hot, or is smoking in the glove box. It’s obvious you already have a problem there, so it’s not like you’re going to wreck something that’s not already damaged. Just bypass the fuse for a few seconds to see what’s getting hot or is starting to melt and smoke. Mechanics like myself have special electronic equipment to pulse electricity through a circuit, but I doubt you’ll want to invest that kind of money and the years of experience it takes to use it correctly. Just realize that BMW electronic parts are normally VERY expensive, and if the broken part is something you really don’t need, you can always just bypass that system by disconnecting it permanently. You just need to discover what part it is First. Good Luck,

Pontiac Grand Am MIL

Willis’s question:

” I just changed the battery out on my Pontiac Grand Am with the supercharged 6 engine. Now I can’t get my car inspected, they tell me too many MIL lights are not ready. They said to drive the car to reset it, but I’ve already gone over a hundred miles and it still won’t pass.”

Answer:

Well, if yours is an earlier model supercharged Grand Am (say a 96-98), then they did have a lot of problems going through the drive cycle and resetting the MILs on those cars. I’ve seen it take 250 miles sometimes to reset them. And realize you MUST drive a while on the highway at 55 mph (use your cruise control, it helps the computer go through the drive cycle faster) in order for it to fully reset itself. Realize that you can have up to 2 MIL not readys in the computer and still pass the emissions test (but 3 mils would make you fail.) So take a good road trip and hopefully it will reset itself. In the unlikely circumstance it won’t reset itself, but still shows no trouble codes, you may have a computer problem that may cause the ECM to need replacing. But try a good long drive on the highway first.

2001 Silverado Fuel Tank Switch

Andrew’s question:

“My 2001 Silverado has two gas tanks. One works, the other just stays full of gas. What can I check to make them both work again?”

Answer:

There’s a switch that makes the tanks change from one side to the other on the dash. I haven’t seen any of those switches go bad, but I have seen a few of the relays that operate the fuel cross over valve go bad. I’d check that relay first as it’s a more common problem.

Vacuum leak testing smoke machine

John’s question:

“Hi you mention on lots of posts in your guest book about getting the air manifolds etc smoke test. Can this be done without having to buy a smoke machine.”

Answer:

Well, you can use someone else’s smoke machine or pay a mechanic. They are REALLY handy for finding vacuum leaks. There are of course older methods that don’t work as well. Such as spraying carb cleaner around and area and seeing if the engine idle changes (indicating a leak in that area.) Guys used to use a little can of propane to do the same thing, but that’s PRETTY dangerous due to the possibility of a flame out burning your car down. And some guys use an ultrasonic sound machine and headphones to listen to where the high pitched sucking sound is coming from (like the Marksman that I personally use at times.) Smoke machines are Fast and Accurate. Now a smoke machine only uses 2 psi or so, so anyone really could invent their own smoke machine using a small fish aquarium pump and any source of smoke. But the smoke machine already built is really handy for us mechanics, as it’s all in one box, easy to use, and does hundreds of cars before it needs its smoke supply refueled.

2001 Grand Cherokee is idling very poorly

Jim’s question:

” My 2001 Grand Cherokee is idling very poorly. I had the computer scanned, but there were no codes. Otherwise, it runs fine. It just idles bad.”

Answer:

Yes, many times vehicles can have an idling problem but no codes will pop on the computer. This is because a problem has to reach a certain parameter before it sets a code. A small problem will often not set any codes. In your case, the number ONE problem like that is simply a dirty throttle plate. So either clean that plate yourself, or have a mechanic do it. It’s a pretty simple job, just get some spray throttle cleaner and remove the ductwork going between the air cleaner and the intake manifold. At the manifold, in that big hole, is the throttle valve. Keep spraying it until the cleaner runs clear (instead of black.) I see that an awful lot in Jeeps that idle bad but set no codes.

PT Cruiser No Spark

Mac’s question:

“PT Cruiser ran hot. repaired mechanical. ran 5 minutes and lost spark. any ideas?”

Answer:

Now it depends upon how hot the engine got. If it got really hot, it could have melted the crankshaft position sensor. With no crankshaft sensor, you’d have no spark. Now pt cruisers have had LOTS of problems with their ignition coils, which may be damaged further by an overheating engine. I change out a lot of ignition coil packs on pt cruisers, so check to see if power is going into the coil, and not coming out to the spark. If you’ve got power going in, and none going out to the spark plugs, then the coil has gone bad. Good Luck,

How to test fuel pressure regulator?

David’s question:

“How can you tell if a fuel pressure regulator is going bad?”

Answer:

Well, there are various tests, and it depends upon which type of vehicle you have. Most fuel pressure regulators are vacuum activated, and you can put a vacuum pressure gauge on them and create vacuum. If they don’t hold the vacuum pressure, they are shot. If you remove the vacuum line going to a regulator and smell gas, then they are leaking gas and are bad. Now some regulators, like those in GM later model trucks, are built inside the manifold and can’t be accessed without removing the manifold and checking them with gauges (a royal pain.)

97 Mercury Sable Wipers Won’t Turn Off

Kraig’s question:

“My 97 Sable’s wipers won’t turn off. I was told to replace the wiper motor assembly.So I put on a rebuilt unit from a discount auto store. It’s still doing the same thing. What’s up?”

Answer:

Well, that is THE most common problem causing the wipers to stay on. The motor and or circuit board in the motor assembly shorts out. Now you could have a bad wiper switch, or a bad general electrical module (a computer part that ultimately runs the wipers). But, before you go that far, I’d advise trying another wiper motor assembly, preferrably a new one instead of a rebuilt one. I’ve had lots of problems with some rebuilders and getting a bad rebuilt Ford wiper motor assembly has happenned to me MORE than once. I’ve personally never changed out a wiper switch on a Sable yet, but I’ve changed lots of motor assemblies. So that will show you what breaks most often.

2000 Kia sluggish acceleration

Edward Horton’s question:

“My 2000 Kia won’t go over forty miles an hour. It has very poor acceleration, but it idles totally normal, smooth as can be. I’ve changed out the fuel pump and filter, but it made no difference at all. HELP! “

Answer:

Well, you took a good guess, but it’s probably another common problem. Now assuming the fuel pump you bought is good (just hook up a fuel pressure gauge and test it–pumps can be bad right out of the box, especially aftermarket pumps), then odds are you’ve got a bad catalytic converter (or bad converters as that Kia has two cats on it.) As I’ve shown in one of my videos, engines have to breathe in and breathe OUT to function correctly. If the cat gets clogged up, then your engine can’t exhale and will only be able to drive up to a certain speed, and no further. Have the cats checked and replaced if they’re building up too much backpressure.