I recently picked up an 04 with 133,000 miles and a six speed that was dead with a bad skreem, and the owner said he had replaced it already twice in 3 years and had had enough. Other than that it appeared to be in pretty decent shape. I determined that it was the SKREEM for sure and sent it to Rob at Needswings to repair. In the meantime, I wanted to find out what was making the car chuck SKREEMS. I checked the battery first and it showed 12.6 volts. Sounds okay, right?. I checked a little closer and found that although the battery appeared to be okay, it was not even close. For starters, it was an cheap battery and was 8 years old. Now for what I believe was killing the SKREEMS. I tested it even further and found that it had 6 milliohms of internal resistance ( 3 milliohms or less is what a new battery will have) and only had 440 cca, when it was rated at 650 cca. I believe that this combination is what crashed the SKREEM. The starting system would have caused huge spikes in current which I think was the culprit. My new battery is rated at 690 cca and has an actual 900 cca. This is a AAA Napa battery and I have found this brand to always be conservative on cca. When I received the new SKREEM from Rob, it started and ran great. Next I did the normal things like oil and tranny fluid change and air filters and belt. I also decided to replace the spark plugs because I figure they were the original and while doing that, I ran a compression test. I put new NGK plugs in it (that is what it came with) and yes it had the original plugs with the Mercedes symbol and NGK R spark plugs. I often read of some owners who run there spark plugs for ever.


I never have believed that if it runs okay, the plugs are fine. I have included a pic to show why to change plugs maybe a little earlier than you think. The car did run great, but the original spark plugs averaged over .080 gap when they should be .040. They were flat used up. I suspect I will get a little more power and better gas mileage, plus the added benefit of not letting spark plugs weld their selves to the block. As for the compression. It went from 139 psi to 145 psi. I will gladly take that, as I suspect a new one would be in the 150 psi range. In closing I think past owners just did not realize that maybe a little maintenance would go a long way in saving a nice car. It really does run and drive great and I have done some other needed maintenance