My 1994 Subaru Legacy has been running unbelievably smoothly for the 7 years that I have had it. It has just over 160,000 miles on it, and our mechanic suggested that we change the timing belt as preventative maintenance. Since that incredible investment (worth over 50% of the car’s value), I have had one problem after another. Once running, the car runs very well, but getting it started is another story. It takes several tries to start, it shakes back and forth, it makes horrible noises, and once the engine finally turns over, it is hesitant to engage the gears. The mechanic thought it may be the cam sensors, so he replaced them. That made absolutely no difference. What could be wrong with this car that was perfectly find until the timing belt was changed?
Not having the timing marks lined up properly during the belt change could cause this.
Hopefully your mechanic changed the tensioners and water pump at the same time as that is the recommended procedure. If not, then he already erred.
It sounds like the vavle timing may be slightly off like OK4450 stated. To see if that is true you could check the compression of the cylinders and see how the readings compare on each side of the engine. If one side shows readings more than 5% different than the other I would say that at least one belt hasn’t been installed correctly.
Do you trust your mechanic?
You say that your “mechanic suggested that we change the timing belt as preventative maintenance.” Under “regular” circumstances – i.e. the maintenance was always performed on time – your timing belt would be due for replacement at 180k miles (every 60k), not 160k miles. So unless you know that the belt was for some reason replaced at 100k instead of 120k miles and thus due to be replaced, losing 20k miles (a full 1/3 of its life) on an otherwise perfectly good timing belt is a whole lot of prevention, not to mention a lot of “wasted” money. Depending on your driving, 20k miles could take 3 years (as it does me).
Now, I don’t “know” your car, but my '94 was the best car I’ve ever owned (and I wish I had it back), so if yours is anything like mine (a wagon with close to 180k miles) was, and it sounds like it might be, the blue book would be somewhere around $2300. Under that assumption, your timing belt job (according to your “over 50% of the car’s value” assessment) would have cost you at least $1100. For a timing belt job? Even if you replaced all of the other things that OK4450 mentioned, it shouldn’t have cost you anywhere near $1000, and something tells me you got just the basic “belt replacement” repair. And I use the term “repair” very loosely here, because it does indeed sound like your mechanic botched the job, on top of taking you for a financial ride in the process.
It seems most places these days have at least one independent Subaru mechanic. If I were you, I’d find one. If your mechanic is one, I’d consider finding a different one. That car should go 300k miles easily. Get it fixed before the engine is toast and have your mechanic cover the labor if it was, indeed, a botched timing belt job.
I would have the mechanic recheck the camshaft timing. He won’t like the suggestion, but the car should run exactly the same after a timing belt replacement as it did before the timing belt replacement.
If the cam timing is off, even just slightly, the engine won’t run correctly.