VVT/Timing chain fail or....??
 

I recently picked up a Mazdaspeed 6 from a local charity auction. It has 119k miles. It was sold as having "a cylinder problem".

Drove it home about 15 miles from the auction. It had a solid miss, but otherwise felt good. No problems sustaining 60 MPH.

I put a vacuum gauge on it and saw that it was fluttering by about 20%. Did lots of research here on the forums and some digging into the history of the car. Found that 5000 miles ago, it had the VVT and possibly the timing chain replaced at a local Mazda dealer.

Did a compression check and got 150/150/150/0. Bought a crappy leakdown tester with a bad second gauge from Harbor Freight. Replaced the second gauge with a regular pressure gauge. It appeared based on a leakdown test that cylinder 3 and 4 were the same. I charged the cylinder with about 40 psi and the 2nd gauge read about 20 psi.

I assumed that they screwed up the previous timing work. Surely, if the valves were bent, cylinder 3 and 4 wouldn't read the same on a leakdown tester, right?

When taking the passenger fender liner out over the weekend, it didn't look like it had ever been removed. Lots of dirt came out from under the plastic retainers that hold it in place. The timing chain is really tight though (no slack). The timing cover has grey gasket goop all around it. It doesn't necessarily look recent though. Is that "factory"?

So, I installed the SSTP and turned the crank to it. The crank bolt hole lined up correctly with the timing cover. I installed an M6 in that hole, to lock the crank in place. I removed the HPFP and the valve cover and installed the SST across the rear of the cams. It did not line up as it should have. Loosened the exhaust cam-to-timing gear bolt and turned the cam to fit the timing tool. It initially didn't look like much, but I was shocked at how far the lobe tip moved. One of the lobe tips was at about 11 o'clock and it turned to 12 o'clock before the timing tool fell into the cam slot.

I put it all back together, hoping this would restore compression to cylinder 4. It didn't. It actually seemed to make things worse, as now the compression was reading 60/60/60/0.

Did I do something wrong, or did the dealer screw this up? I assume my valves are bent, now?

Thoughts?

did you make sure you were at TDC on the intake stroke? the lobes should look like this with cyl 1's lobes pointing @ a 45deg angle twoards each other.

http://farm4.staticflickr.com/3736/9...f6181735_c.jpg

Yes.

I figured that out when the slot on the exhaust cam was below the surface of the head. Figured out that the slot is offset. Turned the crank to TDC and verified the lobe positions compared to another similar photo in the VVT How-to thread.

So your exhaust cam was retarded. it's possible that it was retarded enough to where the exhaust valve is still open when the piston hits tdc on the exhaust stroke giving you 8 nicely bent valves. The oem pistons have no valve reliefs on the exhaust side.