What is a cylinder misfire on my 2002 S60 Volvo?
Asked by missjan Nov 08, 2013 at 10:33 AM about the 2002 Volvo S60 2.4T Turbo
Question type: Maintenance & Repair
Diagnostic stated "cylinder misfire" after I was stranded on the highway when the check engine light came on and car started to shake and was missing. We changed all 5 spark plugs. Mechanic stated we should drive it about 100 miles and this would resolve the problem and the car would be fine, engine light would be reset and go off? Is this true? I find this very hard to believe and read that we should change the coil but which one? Where are they located? Please help!!
6 Answers
need to see which cylinder is misfiring first. swap coil to a diff cylinder and see if the swapped cylinder starts to miss, if the plugs were the culprit it would be running fine after the tune.
migration_judge_roy answered 11 years ago
I believe that this is a grounding issue...undo the main Ground connection and wirebrush the connection to allow the NEGATIVE to flow from the coil packs~
migration_judge_roy answered 11 years ago
5 cylinders are a very elegant design as the spacing is 72 degrees....even steven~
migration_judge_roy answered 11 years ago
...see the starter motor wants to have a 300 or more amp connection...the ECM or ECU wants a perhaps a 750 mA connection...they really do not belong at the same party....but automakers put the ground all in "one basket" and when the 1/0 cable gets corroded from repeated high amperage starts fusing the connection between dis-similar metals creating a "brown power" condition....the ECM cannot think from varying available amperages things get screwey....a solid ground connection is paramount~
migration_judge_roy answered 11 years ago
...well if the problem causes the CEL...the problem goes away....logically the CEL will go away as well....the coil is at the end of the spark plug wire...a "box" with the coil in it~...this really sounds like a ground problem...you mechanic should own a wire brush...he should have disconnected the main ground connection and wirebrushed it clean of all corrosion insuring a steady 12 volts (on the negative side)....this is an easy thing to do and will restore the ground connections needed for the ignition~ all coils are top O each cylinder~
I read a volvo bulletin at the public library that agrees with these assertions. They also cited adding of cerrated washers was not good. And the surface area the connection had originally was required. coating the connection after it was restored to protect it was recommended to block contaminants and the air. Any tech who can diag a misfire can swap and find the causal part. substituting it to another cylinder makes total sense. the problem follows the causal part to the neighboring cylinder.