MECHANIC QUESTION~Please !?

Question

I have a car that is a 6 cyclinder, is 7 yrs. old, has 85,000 mi. on it, one cylinder has a 30 point difference in the compression , (less) than the others, is this a really big major concern? The engine light has come on one time.

Answer 1

WHO MADE THIS THING~!! it makes a BIG difference. A small diff in pressure is NOT all that unusual, BUT it can mean that your RINGS rae very polluted or coked up. This is an EASY fix, but it DEPNDS upon WHAT year and TYPE of truck this is. Get a FULL MOTOR FLUSH to remove all traces of COKE and SLUDGE and VARNISH< and switch over to MOBIL ONE "0" series engine oils. IN TWO DAYS the compressions hould normalize again. BAD oil causes LOTS of troubles on down the road, and STAY away form chaep REG oils and chepa oil change centers, REALLY! they use BAD oil to make more money and ALL engines will suffer from this. GOOD LUCK!!

Answer 2

A 30 psi (not points cylinder compression is measured in pound per square inch), when you do the compression test you are really looking at an inconsistency between cylinders. Which is what you have found, and low compression means the pressure is escaping through one of the valve openings (because the valve is improperly adjusted or worn), down past the rings on the piston or through a blown head gasket, or the cylinder itself isn't sealing well with the piston. We can rule out the head gasket issue as you aren't noticing any other symptoms, also most of the time in a worn head gasket situation I have noticed that 2 cylinders tend to have low compression and are next to each other. Also you should have also done a wet compression test and looked for inconsistencies as well (you inject a SMALL amount of oil in the cylinder and check compression as well) if the number with he wet test is higher then the others its the the cylinder bore issue, if its lower then the other cylinders wet it is. Also the fact this engine has relatively low mileage for 7 years I would tend to move toward a worn or valve adjustment issue or worn piston issue. So that is where I would check, any time compression is an issue it is a major problem because you can have issues down the road.



Best of luck, and check out one of my friends videos on compression testing he was a Honda Mechanic like me he knows his stuff: http://www.youtube.com/watch?v=X_tbksFYhl4





Also in another question you said you had a code P0303 any any time you see a code P030(X) means that the engine computer ECM detected that the cylinder number X misfires; which leads me further to believe you may have misadjusted valves, something worn in the valve train or the exhaust gas recirculation valve is stuck open. Bottom line its time to go see a mechanic.

Answer 3

So the last time you were on you said the engine light was still on and what about the P0300 code you mentioned before? You just have a need to get on the net? Is that what they calling trolling?