My 95 Jetta has a problem no mechanics can figure out I need help..... When she starts she sounds like she is about to stall like she needs a tune up. When she is running for about she is not bad. the mechanic thought for sure it was the injector so he replaced it still the same thing. She has been to three volkswagen specialists and still the same can someone please advise.
Have the car in the dark. Set the parking brake to keep the headlights off. Maybe cover the parking lights to minimize light leakage from them. Let your eyes adjust. Try starting the car in the dark and look for arcing under the hood, including around the coil pack.
First thing I'd do is replace your mechanics. What area do you live in? Hopefully someone here can recommend a good one.
Second thing I'd do is check all your air hoses. The intake hose, the vacuum hoses, and the emissions hoses. One goes to the EGR valve and is "hidden" under the intake. Replace 'em if they're hardened, lose, split, etc.
If the rubber vacuum hoses are original they'll have a plastic/cloth sheath around them. In that case I'd replace them even if they look ok.
Another "hose" to check is the PCV pipe that comes up the front of the engine on the passenger (right side of the car). It gets moisture and oil built up inside and rusts the inner pipe until it's easily broken. Huge vacuum leak.
Make sure the pipe on the intake hose to ?? up near the firewall is on too. I forgot that once and couldn't figure it out for awhile. Also a huge vacuum leak.
Make sure the clamps on the intake hose are snug. If the cap and rotor haven't been done for awhile, inspect and replace if you think it's necessary. Spark plugs too. A special tool makes pulling the OEM plug wires much easier. I made mine. (link below) Replace the air & fuel filters. That's about all there is to a scheduled engine tune up.
After that, it's basic engine trouble shooting. Is it fuel, air or spark? Tom's got the right idea for spark, so try that.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.