sky: were u saying dealer had all the spark plugs replaced? or do u mean the actual spark plug wire? cuz i think ML350 has individual coil?!?!
all spark plug wire replaced
anyways, ML350 with 70k, it's not a very high mileage that the dealer would have changed all the spark plugs for you (happened to a friend's CLK430, dealer took the plug out and "cleaned" them; threw them back in and CEL came back 2 ~ 3 months after, friend recalled they said the plugs were changed; i took them out regardlessly because of the S430 story, found out they were still the old one; my friend was about to drop by the dealership with his invoice, i found that they were not even replaced! it could be a mis-communication between my friend and the dealership, or the service advisor and the tech); double check the invoice and if they were only cleaned, give all the spark plugs a try?
also IMO your car has "unreasonablelly" low mileage for the previous year, spark plugs could have been fouled with unburnt fuel (even if they were just cleaned, better if they were replaced); have seen that happened onto a lot of the european cars, they really need a good warm up / heat cycle everytime u drive it; that's why european cars can take bosch spark plugs, but totally not recommanded on japanese...
also what's the actual code u are getting? Mis-fire? Multiple Mis-fire? a good way to find out if the coil is dead is to swap it with another cylinder, the check engine code will tell you so (more accurate than measuring the resistance)...
with such a low mileage car, moisture in gas tank could be another reason; you probably won't be able to finish up a tank in a month so if u leave the tank empty (low level) for too many days, moisture in the tank (regardless which gas station u go) will cause the car to run rough, hard to start; those can cause fouled spark plugs as well?
have u tried a diff gas station? like from chevron to petro can, or from petro can to chevron etc?
i just picked up my friend's corolla, 07, 2900km since end of last april; car was not driven for about a week but it was rarely driven even tho when his mom is around; as soon as an oil change is done and i finished up that tank (1/4 left when i picked it up), put in some chevron 92 and the car is totally diff (friend's mom was using 91 from shell)...she is so happy with the diff, and was surprised just a diff gas station would make such a change (she first thought oil change is not necessary, as toyota told her it's not due if it's not 8000km)...
all in all, servicing a vehicle involved a lot of infomation from how the owner uses it (such like my friend has a S2000 but that's his weekend car, he NEVER drives it during weekday and even it's a 06 with 12k, i can see moisture has already contaminated his oil; it's only his 2nd oil change ever since he bought his car lolz)...
i guess driving distance, warm up period, choice of gas, and many other things would affect how a mechanic works on your car; 03 with 70k is not decent average mileage, but the mechanic probably wouldn't know u only have 4000km since sept 06? |
發表於 2008-1-12 00:42
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