Compression Test Car Wont Start!!

[Miccheck02]

would a compression test tell me if i have bent valves? Timing belt lost some teeth at the crank.

[djwimbo]

If your timing belt stripped the chances of you having bent valves is great.

Without a leakdown test tool you can't say exactly that they're bent(or which ones), but a compression test would tell you if there's a serious problem. If your compression is low or nonexistent and your belt stripped I would say the valves are bent. Then again, if your belt stripped on a 1.8T and it doesn't start, you pretty much need to pull the head anyways.

Otherwise if you want to check another way, pull the valve cover off and look at the cam followers. 95% of the time when valves bend the cam followers will be "down" and not touching the cam lobes. It's a start to assess the damage

EDIT: depending on what was going on when it stripped, you might only have to replace 2 valves, or up to 12. I've never seen all 20 bend.

[oface]

How many miles does your car have on the timing belt since the last change?

[Miccheck02]

only 79k never changed i was gonna change soon i might be covered under the class action i am in the middle of it....what are the cam followers?

[djwimbo]

....what are the cam followers?

They look like this. The side that's up in that picture is touching the top of the valve stem. The side that's up in the cylinder head is smooth and should be shiny. It's the equivalent of a lifter in V8 in block cam engine.

[Don Supreme]

You should be able to tell if you have the kind of bent valves that a timing belt failure often results in.

Just crank the motor --- It will sound COMPLETELY different, like it has no guts. Just an empty whine as it spins and is not pushing against compression resistance.

[Audi Skate Snow]

compression check will give you a good gauge of whats going on.... a Cylinder Leak down will tell you what valves are bent (exhaust or intake valves) if any.

like don said also.... you almost can tell from the sound of the cranking if you have lost compression.