So my wifes 94 Camry died while driving on the highway the other day. Long story short, the compression on two of the 4 cylinders are very low like around 75PSI (should be ~175) The timing is 10-15 degrees ahead of TDC.

I took off the timing belt cover to look at the timing marks. With the crank pulley mark on "0" (TDC), the camshaft marks did not align exactly. The hole (mark) on the camshaft pulley was about 1/8th an behind (to the left) of the mark on the bearing cap.

So does that mean the belt "skipped a tooth"?

Would the belt being off a tooth result in the very low compression I got from my compression tests?

Just wondering if it's a timing issue or if I have much bigger problems....

Thanks for the help !!!

 

Sounds like the belt jumped, and that could cause low compression if the valves timing is off and they are not completely closed when the piston is at tdc.
Or worse case maybe it's an interference engine, and the valves are damaged.

 

It's a non-interference so hopefully it's just the timing belt issue....

thanks for the response!

 

An eighth of an inch off on the cam mark may just be the way you induced slack in the belt according to the way you last turned the crank. Certainly not enough to kill that much compression. The Camry has a high incidence of head gasket failures too but Toyota tries to keep that quiet. My sister's failed at around 150k miles.

If the Camry has some miles, you need to perform a leak down test and check the cooling system, chemical test, for hydrocarbons. I think you have a head gasket problem.

Is the low compression on two adjacent cylinders?

 

yeah the low compression is on two adjacent cylinders...Never heard of the camrys having HG problems but sounds like that might be the problem (it has about 150K). I blew a HG on my 3.0 4runner but it showed the symptoms of the white cloud of smoke (coolant in exhaust and) and milkshake like oil on the oil cap , etc. According to my wife, the enging just died. no smoke or anything. but i just checked the coolant level and it is down about a quart...hmmm I'll try a leak down test next.

thanks for the help

 

Yes i'm willing to bet your belt skipped. 4 cyl tbelts have a history of stretching and flopping around in the timing covers even at early mileage. This can affect your compression if its off. The camry do not have a bad history of h/g failures. I have only done 1 or 2 in 10 years myself. The 02-03 4 cyl camrys however have problems with the cylinder head bolt holes in the engine blocks. The back middle 3 holes pull the threads out causing external coolant leaks. I have both repaired and replaced those engines. Toyota is keeping that very hush. They are very aware of the problem and issued a TSB not for the failure but to say there is an updated engine block for those. Only the 02-03 are affected