It may be too late, but I did the same with all 12 coils. However, I found the identical Bosch coils at amazon.com for half the price the dealer wanted.I had PO301 to 306 codes and so I changed all 12 plugs and boots. Plugs are 60K miles old so it is probably time anyway. Changed coils on 1-6, based on misfire codes. Also changed coil on #12 since it is difficult to get to. You have to loosen the wiring harness tray to gain easy access. #11 was done by the dealer a few years ago. I replaced #10 because the tip broke off when I removed the boot. Seems to run better , but have not driven on the road yet. Will watch to see if codes come back.
May order a new MAF Sensor since I also got a PO170 code.
I think I bought my coils from Autohaus several years agoat $50-55 each. Much less than dealer. I just found the MAF on Amazon for $110. Finding inexpensive parts is almost as much fun as searching for a replacement W140, C140 or R129!It may be too late, but I did the same with all 12 coils. However, I found the identical Bosch coils at amazon.com for half the price the dealer wanted.
I probably need to replace both intake air filters. I can still feel a little shaking in the seat at idol. I am sure it is time to finally replace the engine & Tranny mounts.I replaced my radiator hoses (22 years old?), new coolant and a new air intake thingy . Car runs like a dream!
Looks really GOOD,gotta treat these cars right and they'll treat us right...I ‘ve driven my ’94 S500 cpe for 20 years . . . and it’s now 25 yrs old. It’s been the most reliable Mercedes that I’ve ever owned with maintenance costs being minimal. After I retired, it has spent a lot of time in the garage for lack of driving.
So it was time to give it some love . . . as this thread says.
1-Started with a radiator flush using just distilled water.
2- Oil change + filter
4-Replaced spark plugs (apx 10+ years old!!)
5-Replaced both side – distributor caps and rotors (apx 15 years old!)
6-Replaced both accumulators
7-Found and repaired ohmic connection to Aux Fans . . . no low speed
8-Replaced windshield washer fill tube and grommet
9-Replaced all four tires . . . 12 years old set
And here’s what it looks like today . . . still in the garage . . temp is 95F!
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