cyclinder 3 misfire

[qt2hot]

I have a misfire on cylinder 3.

had it checked and it only has 25 lbs. of pressure is there anything i can do besides having the engine taken apart

[BNaylor]

Please be sure to post the mileage, year and we are assuming you have the SII 3800 engine?

If that is engine compression the reading is unacceptable and sounds like tear down time.

[qt2hot]

Originally Posted by BNaylor

Please be sure to post the mileage, year and we are assuming you have the SII 3800 engine?

If that is engine compression the reading is unacceptable and sounds like tear down time.

Yes it has the II 3800 and it is a 1998 intrigue with about 132,00 miles

[dizzle1]

So the valve guide's are bad its not ignition related did u crank it a enough and take off the other wire's to test smoother

[harmankardon35]

check your cooling system for bubbles...headgasket failure can easily cause low compression....

[stretch80]

Originally Posted by qt2hot

I have a misfire on cylinder 3.

had it checked and it only has 25 lbs. of pressure is there anything i can do besides having the engine taken apart

I had the exact problem on a 99 Olds 88 with the 3.8. Problem was intermittant. Checked wire, plug and coil. All checked okay. A couple of thousand miles down the road I also was using antifreeze. Searched but could not find the leak but noticed snot looking goo on inside of oil filler cap. This inidicated antifreeze leaking into engine. Did a pressure test on the cooling system found external leak at throttle body end of upper intake manifold. Antifreeze was leaking externally and internally into the engine. Due to the location of the leak and the slope of the engine antifreeze was leaking into cylinder #3 and causing a misfire.

Replaced upper intake manifold with an improved design that does not cause the EGR gas passage tube to warp the intake manifold. Problem solved and that was over 80,000 miles ago. I have talked to others who in addition to the above regasketed the lower intake manifold