i have a 1986 bronco i hooked a compression tester onto the first spark plug valve on that front of my straight six engine and its only showing 30 lbs of pressure on the tester....what possiblities am i looking at to fix here...could it be a blown valve or something else? when truck is running, and the spark plug is in the cylinder valve, when i take off the distributor wire from that cap theres no loss of power, but when i dissconnect the others, there is loss of power. please help with all your possiblities and how i can fix it.
2007-03-09 12:52:31 · 2 answers · asked by Whitney D 1 in Cars & Transportation ➔ Maintenance & Repairs
Did you compare the readings on other cylinders to the one you say you checked? It wouldn't be the first time a compression tester read lower then actual. Usually it's best to get a comparison to all the cylinders to determine any "bad" ones. The only reason I'm bringing this up is that you didn't mention if you'd checked the spark plug/plug wire to insure you had a good, hot spark to that cylinder. I'd hate to see you dive into the motor when the issue was ignition related.
2007-03-09 13:23:41 · answer #1 · answered by nick_nunya2003 3 · 0⤊ 0⤋
hi,obviously you have low compression,on #1,could be a burnt valve,sticking valve or a worn out cylinder,piston or rings.(definately internal engine problem) The only other thing you can do before tearing it down is a leakdown test.(this will tell you where the problem lies.You need compressed air to do this.If you wish to do the job yourself without further diagnosis,start with removing the valve cover & watch the valves for that cylinder.(while turning the engine over)If all looks fine,the cylinder head will have to come off for further inspection.Look at your mileage though,maybe a good rebuilt engine is better than a patch job.Good luck
2007-03-09 13:13:52 · answer #2 · answered by giff01 3 · 0⤊ 0⤋