Valve Adjustment 1zzfe - Toyota Nation Forum : Toyota Car and Truck Forums

medicstudent01 · 11-27-2006, 09:39 PM

I was searching through AllData looking for some info on the problem I have (2001 Prism w/ low compression #2 cylinder). I came across a section on valve clearance and how to check it.

To make a long story short, I checked valve clearance on the car and found 1 exhaust valve on cylinder #2 has NO clearance. Basically the valve is always open a hair causing very low compression on cylinder #2. I would assume either the valve is damaged or the valve is recessing in its seat thus tightening up clearance.

Anyways I put the engine at TDC and made marks on the cam sprockets to timing chain position. I then pulled the timing chain tensioner, and then removed the cam sprocket then cam. Alldata tells you to pull the front cover to pull the cams, but I think it will work without pulling the front cover.

Anyways I am going to mic the original lifter and get one thats shorter to compensate. Hopefully the valve seat/face is still good and the head wont have to come off

Anyways, any comments on this? Am I retarted, or do I have a chance of getting this car fixed???

***toyomoho*** · 11-27-2006, 11:12 PM

Readjusting the clearance is worth a try. Suggest doing it ASAP to avoid possible (or any more) damage to the valve or valve seat by combustion gases. This engine might use a differant type of seat construction other then the usual steel insert.

retiredat44 · 11-28-2006, 12:33 PM

that would be very unusual to have the clearance closing,, wear always opens clearance.. sorry, but your problem has me puzzled..

medicstudent01 · 12-08-2006, 10:30 AM

Not on this engine. The lifters sit right on top of the valves/springs, then the cam sits on top of that. As the valve sinks into the head, it tightens up the valve clearance.

The car has 125k on it. Looks like the valve clearance was never checked. I found that the exhaust valves were overall to tight (Normal .010-.014), and mine were all around .007. And one had NO clearance leaving the valve cracked open a hair causing no compression.

The intake valves were still within spec. Normal was .006-.010 and mine were all .006.