Back To Basics
I get many, many letters everyday looking for help and suggestions on what a problem may be or caused by. Many times the answer is very simple. The fact is modern fuel injection systems are very robust and reliable. Yes, things do go wrong but nine times out of ten it is something simple and stupid that should have been checked first. I know a lot of professional technicians, myself included, that have been bitten on the ass by not checking the basics first. It's almost like building a house. You don't build the walls or roof first. You build a good foundation first. Troubleshooting is the same thing. Why look for an electrical problem for three days when simply changing a fuel filter would solve the problem.
When you have a problem you're trying to fix, there are some basic checks to make no matter what make or model car you have. This are simple things to check and do not require any special tools.
For an engine to run, you need three things:
- Air (Vacuum, compression)
- Fuel
- Spark (Electrical)
Without any one of these things the engine will not run.
Air
The air intake system is pretty simple to check. The first, and most obvious, thing to check is the air filter. Some air intake systems are designed in a way that small animals like to move in and call it home. I have pulled real rats nests out of some air cleaners. I had one customer who wrapped window screen around the air intake to keep squirrels out. It only takes a few minutes to check an air filter. If you hold it up to the light and you can't see through it, throw it away and put in a new one.
Another thing to check is the tube that connects the air filter housing to the intake manifold. It is designed to flex and over time they dry up, get brittle and crack. Look for small cracks at the bottom of the bellow folds. Cracks there will allow un-metered air (air the computer doesn't know about) into the engine, causing a lean condition.
Further up the line is the throttle body. A lot of air gets worked and routed in here. It is also a great place for gum, dirt and varnish to collect and clog up small air passages. Believe me, a lot of driveability problems are fixed just by cleaning the throttle body.
Fuel
In the fuel system the fuel filter is the weak link in the chain. Fuel filters will cause all kinds of driveability problems that you may not relate to at first thought. If you have a driveability problem such as loss of power or stalling, one of the first things to do is replace the fuel filter. It's a simple thing to do and could very well fix the problem.
If the car doesn't start, check the battery. The battery has to be good and fully charged. More often the question is "Does it crank?" but "Does the battery voltage stay above 9 to 9.5 volts while it is cranking?" Most fuel pumps will not run on less than 9 or 10 volts. Check the fuel pump fuse. Is it blown? If it is, that's an excellent reason for not starting.
Copyright © 2000 - 2003 Vincent T. Ciulla All Rights Reserved
