Opinion: New engine or new car? 2003 VW Jetta

Hello Everyone!

My brother has a 2003 Volkswagen Jetta with 155,000 miles on it. The other day, he started it up before work, went out about 10 minutes later and the car was off… it hasn’t started back up since. We towed it to our local mechanic and the mechanic said the timing belt came off. I guess there were no teeth or anything left on it. Anyways, the timing belt will cost about $400 to get put on by him, and then he will know if there is any engine damage. A used engine with 79,000 miles installed will be about $1250. He said since the car was idle when the belt snapped, there is a chance the engine was saved… however, he said judging by the clicking sound when trying to turn the engine over while starting, he suspects there may be damage.

So, my question to anyone with knowledge of this… should he pay the roughly $1650 (possibly) for a new timing belt and motor, or just get rid of the car. The car is in rather good shape otherwise. The fuel pump was just replaced. The transmission pauses a little bit when transitioning between the lower gears (its automatic), but it has been doing that for years. And, this car is used primarily for highway driving… it gets about 35,000 miles on it a year. So, if he would go purchase a different car, he may be in the same situation in a year or so. So, I guess I just want to know your oppinion if it would be worth investing the money into this car.

Thanks so much for any advice and direction you can provide!

There is no reason to install a new timing belt to determine if there is engine damage. That can be determined without replacing anything.
Bent valves due to a broken timing belt does not automatically mean the entire engine is trashed; only that cylinder head valve damage has happened and that is repairable.

If a used engine is installed there are certain things that should be done to that before the installation. This would include a new timing belt kit, torque converter seal on the transmission, etc.

A bit of a tough call and it’s difficult to offer a definitive answer based on the belt kit to determine damage and the lack of a belt kit on a used engine. With a used engine you never really know for sure what you’re getting.

What engine? If it has any 4-cylinder, then it is an interference engine. If it is the V6, it is not an interference engine. In an interference engine, the valves and cylinder share the same space, jut not at the sam time. When the timing belt breaks, the valves fall into the shared space. As the engine turns, the cylinders are cranked into the valves. You never know for sure until the head is removed and the valves/cylinder are inspected for damage.

Thanks guys! It is a 4-cylinder engine. And, the mechanic did mention about the valves possibly falling. I’ll have to ask him if there is a way for him to inspect it for damage without replacing the belt.

Out of curiosity, how many miles and years were on this timing belt? It wasn’t the original, I hope?

It was a used car that was purchased at about 85,000 i believe. It hasn’t been changed since. So, it was definately due. Not sure if it was the original.

I would rather get that cylinder head repaired (if necessary) rather than taking a chance on a used engine (which might be overdue for a timing belt job)

You can buy a used cylinder head from a junk yard and have it rebuilt. I did this with an Austin America many years ago and it worked well.

My neighbor had this happen on a VW Passat 4 cylinder and it cost $3000. So, if you want a proper fix, brace yourself for that amount. I would go for a good used engine, but the cost will be about the same.

timing belt job is time consuming and has parts so it costs 400 or so. removing head is a bit more work and also may include replacing valves, resurfacing and so on and ends with new timing belt and water pump.

I’d get a second opinion. The mechanic should know if there’s damage or not before throwing parts at it.

I’ve put engines and transmissions in cars before, as long as the body holds out I see no reason not to, but it may just need the head rebuilt if it’s just a bent valve or two. It’s generally cheaper in the long run to fix than to replace.

155,000 is too much for a timing belt, it should have been replaced. Usually the manual recommends between 75,000 and 100,000 miles between changes. If the original lasted that long then he’s been driving on borrowed miles.

Your mechanic cannot perform a compression test without first putting a new belt on, but he can still check the valves. He can perform a leak down test. He will need to remove the valve cover and the spark plugs, then put in the air adapter and pressurize the cylinder and see how long the pressure holds.

The reason for removing the valve covers is that he will need to turn the cam to the TDC position on the compression stroke for each cylinder under test. There should be a set of flats somewhere on the cam to put a wrench on to turn it. If not, the timing belt cover will have to come off so he can turn the cam(s) using the cam gear bolt on the front of the cam.

If it passes the leak down test, then he should insert a flexible camera into each cylinder to inspect the tops of each piston for defects that could make a hot spot. Inspection cameras, aka borescope cameras are getting cheap now so every mechanic should get one. I saw one at WalMart for $80.

With that information, which your brother should expect to compensate the mechanic for, probably one to two hours labor, then you/he can make an informed decision. at least this way, it is cheaper than putting on the belt and then finding that the head needs to be replaced/reworked and then have to pay for the belt labor the second time.

Everyone seems to agree this is an interference engine

Turning the cam with no regards to the crank might result in further collision between the pistons and valves

To do a leakdown test, I’d make sure both valves are closed (cam lobes pointing up, because this engine probably uses buckets) AND the piston is at tdc

Put me in the bucket of option 3 which is neither new (used) engine nor new car, but new cylinder head. That is, after checking for valve and piston damage. If there is piston damage, I’d probably go for a used engine, but I’d usually rather fix the devil I know.

Do note that if you go for a used engine to ask them to make sure to figure a full timing belt kit into it. You don’t want a used engine with its old timing belt and components or next week the car might very well be in the very same spot. If its a good shop they should not charge you the standard labor because this work would be done BEFORE the used engine is installed - which means that the labor to do it would be a lot less than the standard book rate.