2003 Type S - No Compression

P

projektdirtfab

New Member
#1
#1
Hey guys. Got a customers car here and were stumped. Figured you guys might be able to figure it out if you've ran across this before.

103k miles
0 psi compression. 30psi on cyl 4. Cranks fast like the plugs are out. Wet and dry test yield the same results. All 4 pistons are moving. Valvetrain is moving and timing marks all lined up. Set cyls at tdc and pressurized with shop air. No drop in pressure from the shop tank. No air coming from intake, exhaust, coolant or oil dipstick....

So it seems the cyls are holding pressure but no compression during cranking....scratching my head.

Thanks
 
Donabed Kopoian

Donabed Kopoian

6 Speed Master
#2
#2
1. How did the cam lobes look? Are they in spec?

2. Any broken valve stems, guides, or springs?

The problem is in the valvetrain somewhere and not in the chamber or the pistons. Almost sounds like the valves are sticking badly. Is there sludge?
 
P

projektdirtfab

New Member
#3
#3
I havent pulled the head to further inspect
But im guessing 120 psi of shop air was enough to close the valves making me think the cylinder is sealed up good. But the slow build of psi from the piston during cranking isnt enough. Lobes look normal. Havent specd the shims with a feeler gauge yet. At tdc with lobes facing up the valve cups can rotate freely by hand...wondering if shop air would close the valves and make it tighter? Than I would know for sure. Customer says no noise was made when the car died. Usually bent valves would make quite the sound...but maybe she wasnt paying attention. Either way I also believe its something in the head...
 
Donabed Kopoian

Donabed Kopoian

6 Speed Master
#4
#4
That's why I'm leaning toward a sticky valve. When engie is at rest the compressed air shuts it. When the engine is starting they stick and never fully close before re-opening. Only way to tell would be to remove the valve cover, remove the fuel pump relay and ignition relay, and turn the engine over while filming the valves, then getting the movie onto a computer and going frame by frame to verify sticking or not.

I am wondering if maintenance was lacking, that is the only thing I can come up with at the moment. (I'd shield the area with plastic as oil will splash out of the head).
 
P

projektdirtfab

New Member
#6
#6
Hi...sorry for delayed response. Havent got to work on the car very much due to other customers priorities. But the valve cover is off. Cams rotate in sync and all marks line up. Were going to pull timing cover and inspect lower timing system. Other than that...the heads got to come off. Customer already has a new car so at this point theres no deadline and theyre not sure how much more money to invest.
 
Donabed Kopoian

Donabed Kopoian

6 Speed Master
#9
#9
103k miles on a 2003 Type S should be able to sell for $6k easy (assuming that everything else about the car is perfect) ... so if they sell it to you for a grand, you could net a few grand from it.
 
G

Gmanns

New Member
#10
#10
Did you ever get to the cause of the no compression issue.
Have an '08 Matrix. appears to have the same problem. 140,000 miles.
Had a 2.5 Jetta with all intake valves stuck open. Could this car have the same kind of problem.
 
You must log in or register to reply here.
Top