96 civic lx. 143k miles auto. misfires and hesitates very badly, sometimes will clear up, take off, and start running shitty again from a stop. compression was 180-177-180-180, only cel is for secondary o2. ideas?

 

Tune up & fuel filter?

 

threw wires and plugs at it somewhat recently. tomorrow, injectors will be tested, and the distributor will be torn down and tested as well.

 

injectors all work. swapped over known good distributor (coil was missing spring in the one that was on the car). new trick: the car is boiling coolant in the reservoir. t stat works, and i literally just swapped the head for a known good y8 head and a new graphite gasket (personal preference). torqued to spec. did the swap because it was boiling coolant before and cyl. 3 had 120 comp.

 

should add- no oil/coolant mix. current compression test was in OP. thermostat seems to work completely fine, ran it until it opened and the two hoses equalized temperature. does not overheat.

 

How's the water pump? Have you tested the ECT sensor to see if its functioning like it should?

 

ect works. fan works as well, cycles on and off normally.

 

Hmm, Check the coolant for combustion?

 

thats next step i guess. going to verify mechanical timing did not jump as well

 

Just check the ignition timing. If it can be set correctly, then the mechanical timing is fine.

 

radiator cap was missing the "button" in the middle. replaced it, and since it is now holding pressure, started leaking badly from a crack in the upper plastic tank. poor running was caused by the car being out of mechanical timing. belt skipped 4-5 teeth, and i have no clue how it happened. belt was properly tensioned, but out of time. it is possible that i messed up, but unlikely... i have done enough of these that i could replace a sohc belt with my eyes closed. i retimed it, ran it @ idle for 10 minutes or so (no drive, bad radiator), checked timing after. spot on. wtf could have caused this?

 

I don't think it's possible for the engine to run with the timing belt off by 4-5 teeth. Just saying.

 

it ran. i didnt think so either. was 3/4-1" away from tdc @ the pointer with the cam @ tdc. it hardly moved under its own power and was actually worse warm. i don't recommend timing your car similarly to see for yourself. i took a cell phone pic of the crank in that position last night for my collection of fail pics, i have a nice "wall of fail" in my garage with extremely broken parts as well.

 

Everyone makes mistakes, dammit I might have to check mine now.....

Yeah man that radiator cap is a major necessity. Good thing you caught.

 

i bought this thing all messed up. had it towed home because the motor had been repeatedly overheated, but it did start and run. at temperature, it was forcing coolant into the overflow. at that time, compression was 180-130-180-180. pulled the head, put a new gasket and a good y8 head. never noticed the radiator leak because the system obviously wasnt pressurized enough for it to force its way out of the hairline crack in the plastic. as soon as i put the new cap on, it started to leak. threw a used radiator at it today with the new cap, bled the system, put it under load (3k rpm for 10 mins) just to try to get it to push coolant/overheat/skip time. so far, so good.