rb20det NO COMPRESSION?!

[giantR32typeM]

so i just got the timing belt, idler pulley, tensioner, cam seals, crank seal, thermostat, water pump etc changed on my r32. i brought the car to the shop running on all 6 cylinders and when i went to pick it up he said that the car was misfiring. turns out he did a compression test:

cylinder compression

#1: 115
#2: 110
#3: 100
#4: 0
#5: 115
#6: 120

does anybody have any clue what could have caused this?

[R32ONP]

broken exhaust valve???? broken ring land on piston or straight melted piston?? a blowen headgasket will normaly pull some pressure but not a hell of a lot...my old rb20 broke a valve and pulled 0 compression

[giantR32typeM]

do you think thats because of a misaligned timing belt? because the car was running perfectly fine on all 6 cylinders when i brought it there.

[R32ONP]

if u mis align the timing belt and run it it will run like s*** (from the valves being opened/closed out of time to the stroke) but if its mis aligned far enough it could brake the valve??? it is quite possible...but either way its got no compression and u cant fix that with the head on so rip the head off and check out the damage...if it was a cambelt mis alignment ull have a broken or maybe majorly bent/leaking valve and ull see it with the head off as theyl be contact marks from the valve onto the piston....rip the head off and post up some pics of the damage??

[ItzGenX]

Yea find out what the damage is by removing the head as stated earlier. I sure hope the shop you brought it to is going to man up for the repair work.

[Joe]

do you think thats because of a misaligned timing belt? because the car was running perfectly fine on all 6 cylinders when i brought it there.

that would affect all of the cylinders, not just 1

the head needs to be pulled and the shop is DEFINITELY responsible for the repairs.

[giantR32typeM]

tomorrow we will be pulling the plugs on the cylinders and checking for scoring on the pistons from the valves and looking to see if the ring has been f'ed on piston #4 with a borescope and be going from there. the shop owner said he will work with me however when i picked the car up he was not giving off that vibe. its a small shop in jacksonville fl that supposably has a good rep among 240 guys however this s*** says otherwise. turned out to be an amateur f*** job. if he decides not to do anything about his f- up he will be receiving endless amts of unwanted advertising... i would think that a shops rep, especially a small mom and pop jap shop would value their rep a tad more than $500 in labor.. at this point this guy will not be touching my car again..

[R32RB20DET]

If no compression most likely it's a bent valve. When the valve are not seated and flush to the block and is not holding pressure is no compression. Sometime bent valve occur from installing the timing belt back on and when is off misaligned. I could be wrong though, but the only way to find out is to take it apart. Good luck.