Coolant loss, misfire, overheating

[joesilvia92]

I have a 96 xlt 4.0 ohv with 220000. So for the past week almost ive been loosing coolant pretty good, almost a gallon a day. Head gaskets were done around 170000. Im pulling misfires on cyl #1 over and over. The truck will mis on start up when at idle but not under load. Could these be related? Compression test came back good as did coolant pressure test. Theres no puddles on the ground, floor isnt wet like a blown heater core. Dont really know where to go from here. Coolant is leaking from somwhere onto the pass side end of the y pipe and also onto the oil filter, Are there any coolant hoses lower on the engine thant could be leaking? The heater control valve is about a year old and none of the heater hoses look as if their leaking. Im at a loss and need to fix asap as this is my only means of transportation. Any help would be greatly appricated.

 

[shooterdude199]

the first thing i would check for the misfires is plugs and wires. as for the coolant leak, check the thermostat housing, thats where my leak was. thats sort of odd. but coolant can't just disappear so there has to be some sort of leak somewhere. or check the overflow for cracks or something.

 

[joesilvia92]

Over flow seems to be fine as does water pump. Think its possible the core is leaking through the plastic a/c housing on the fire wall? Could the head be leaking due to a cracked head near a coolant passage and show no signs of major coolant loss?

 

[deweyville65]

I know you said there are no puddles on the ground, only coolant around the oil filter. Have you gotten under the truck and checked the freeze plugs? Nearly a gallon a day, to me, is MAJOR coolant loss. I would suspect it is going into the engine and being burned.

 

[joesilvia92]

I haven't had the chance to check from below yet. I did however look with a mirror and flashlight and freeze plugs I've seen looked ok yet possible I missed one. I'll have to get under it on a dry day. are plugs on these engines known to let go?

 

[jamessavage]

I'm with Dewey. Misfire + coolant loss and overheating, ESPECIALLY at a gallon/day sounds like blown head gasket losing coolant to #1. I'd fill it and let it set for a while over a big piece of cardboard to see if it's losing coolant from a leak. After a few hours, start it up and let it idle for an hour or so. Check for external leaks again. If neither produces a leak AND you still lose coolant, I'd bet on that gasket.

Have you looked at the oil? Could be some coolant signs in it if the head gasket is pooched.

 

[Turdle]

Leaking onto the y pipe is almost always a heater core leak.

Insert a double ended barbed fitting between the 2 heater core hoses to bypass the heater core, then refill coolant and see if the leak is now contained.

 

[joesilvia92]

No sign of coolant in oil or oil in coolant no signs of water in trans. Radiator was done this summer. No stench of coolant through the exhaust. Head gaskets were also done on this motor at around 170000. And I ran a compression test on cylinder #1 and all cylinders on that head and it passed.

 

[joesilvia92]

Thanks ill have to bypass the core and see how it does. I'll keep you updated.