I've got 160,000 on my 05 Liberty and this just started happening. First was the misfire (but #2 cyl), then I put in plat plugs (which I am going to replace right away) and then it overheated. Replaced the water pump, the thermostat (acted like a thermostat issue but at 160k I thought what the hell). Then it still ran hot so I pulled the radiator and found out it was 70% clogged. Replaced the radiator and all was well for two weeks then the misfire happened again. Runs rough at start up then levels out.

Then my wife pulls in the drive and I see water pissing out from the new radiator. Pulled it out and took it back and am getting it replaced under warranty and my radiator guy says it looks like a pressure problem blew it out and I may have a head gasket leak allowing compression gases into the coolant system. Hmmmmm, would the recovery tank handle the extra pressure though? darn I hate to tear into this thing. Its been rock solid for this long.

Can a head gasket leaking into the coolant system do this? Would a leak down compression test find this?

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Jack Sharp
2005 Jeep Liberty Limited
1990 Mazda B2200
1874 Suzuki TTR250 (project - under renovations)

If the head gasket is bad you should be able to pull the plugs and see coolent or a different look on the leaking cyls plug. The exhaust may also smell of coolent at start-up. Hope that helps.