Mechanics? (car help needed)

me | 3/11 | me

[Charlie OK]

If there is anybody that knows anything about cars or knows of a good free website that will answer my question, could you chime in here?

My problem: I have a 99 protege with 53000 miles on it, and the check engine light is on. I took it to one of those diagnostic centers about a week and a half ago, and they said they couldn't tell what was wrong with it, and they reset the light. They said it was probably nothing urgent, so don't worry unless it comes back on. Well of course, it came back on.

The only problem I can seem to detect is that sometimes I have a problem accelerating, like if I pull onto a road from a side street, I have to have plenty of room because my car is very slow in picking up steam. I looked at the air filter, and it seemed pretty dirty. Would a dirty air filter cause the light to come on and the engine to weaken? Money is tight so if I can avoid a mechanic or can take care of this with just a new filter, I will be extremely happy.

[Charlie OK]

Thanks for any help you can give me...

[El Sordo]

It sure wouldn't hurt to change the air filter.

[Charlie OK]

you think that would make my light come on though?

[ThinkingMan]

You may also want to check the fuel filter. I don't know where they are located on the type of vehicle you mention, but if you get underneath and follow the fuel line from the tank to the engine, you should see it. Most fuel filter are little canister shaped filters. If you take it off, make sure you are wearing safety glasses- fuel in the eyes really sucks. When putting a new one on, make sure you put it on the correct direction- the arrow pointing toward the engine. It is a relatively cheap fix with minimum work involved, just a couple of hose clamps.

Hope that helps.

[Charlie OK]

thanks. may try to replace the air and fuel filters. wish me luck, as you can tell I am very mechanically-impaired.

[familyof5]

My experience has been that the light comes on when either the O2 detector goes or the PCV valve goes. Both throw off the fuel mixture and result in acceleration problems. Both are easy to replace and are not too expensive.

[ThinkingMan]

PCV valve is a good idea- should of thought of that!

[El Sordo]

If you can replace the air filter easily enough, do it. Even if just for peace of mind. The odds aren't great that this will fix your problem, but it will help eliminate it as a question mark.

I'd advise not changing the fuel filter without proper tools and procedures. The modern fuel systems tend to be highly pressurized. Usually there is a procedeure for disabling the fuel pump (commonly by removing the fuse) and running the engine until the fuel system is depressurized. A good set of flare fitting wrenches can be useful for working with any type of pressure lines. The filter housing tends fo be steel, but the fuel lines likely attach with flare fittings or other type of compression fitting. Regular box end wrenches can damage these fittings if you are not careful.

No real good short term answer for you there, sorry.

You might see what Click and Clack have to say:

http://www.cars.com/carsapp/national/?srv=parser&act=display&tf=/advice/caradviser/car_adviser_index.tmpl

[T. P. Pole]

On cars made after (I think) 1996, there is an on board computer. This is mainly tasked with emissions (smog). The check engine light goes on if the computer thinks you are polluting. This can be anything from a misfire or the PVC valve, or the O2 sensor, all the way down to a gas cap not being tight.

Some car parts places will let you plug into the computer and scan the codes (in the computer). There is a base set of codes, as well as a few custom ones. You look up these codes and it will tell you what is likely wrong.

If a repair shop cleared the codes and then the light came back on, then you likely have a "real" problem. PVC or O2 sensor is the most common cause.

Good luck.

[hottomale]

Temp. sensor went bad in my chevy. Caused hard starting and bunny hopping until the engine came up to temp.. I have a Chiltons manual for mine specific model. My recommendation is to find a local library and read a little. Sometimes a local mechanic can be of help. Even dealerships might be having a good day and would give some estimate of what is wrong. My manual goes into detail about the check engine light and the diagnosis of the different occurances. I don't even know what a protege is but good luck.

[Charlie OK]

thanks everyone for chiming in. Looks like I will definitely replace my air filter and will see if I can do the PCV valve myself. Hopefully that will do some good. We'll see.

[cdefreese]

Other than the acceleration, do you hear or feel anything that may be wrong?

My old car sounded like it needed a tune-up real bad. I thought something bad was wrong, I had no acceleration, the engine was a little jumpy, and I thought it might be the timing. Luckily I found out after a little investigating that one of the spark plug wires had came off...

Another time I had a real clogged fuel filter, and gas wouldn't get to the engine fast enough to accelerate like I'd liked. Check that, and any cuts in the fuel line.

I'd hope that the diagnostic place would had found that. I'd replace all the filters and the PCV valve.

[Charlie OK]

Thanks. That sounds exactly like what the mechanic I just spoke to said. Spark plugs and fuel system the likely culprit. He definitely said the car was running "too lean".