96 E320 Plugs & Wires
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Joined: Apr 2005
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From: Boston
'96 E320; 170K miles with extensive rust!
96 E320 Plugs & Wires
Changed the plugs and wires today. Started up but with a rough idle; and CEL. Diagnostic code is P0300 random misfire. Reseated everything and same problem. I was very careful not to stress the wires which go to the harness. Any suggestions? Thanks.
Super Member
Joined: Mar 2006
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From: Bellevue, WA
.... nothing to brag about, it is a previous model....
Originally Posted by BostonC4S
Changed the plugs and wires today. Started up but with a rough idle; and CEL. Diagnostic code is P0300 random misfire. Reseated everything and same problem. I was very careful not to stress the wires which go to the harness. Any suggestions? Thanks.
check the wire sequence? also are those plug within spec?
distributor cap?
I-6 is much easier to work w/, but try putting old plug back?
Or try putting old wire back?
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Joined: Mar 2002
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From: Arizona, USA
W205 C300
What kind of plugs did you put in? Only use copper plugs in the M104 Inline 6. It is best to use the stock Bosch ones that are the OEM installation and gap them correctly. There is no distirbutor to worry about but you may have a weak coil. Each coil is used for 2 spark plugs so it may be randomly firing either one.
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Member
Joined: Apr 2005
Posts: 85
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From: Boston
'96 E320; 170K miles with extensive rust!
I installed the Bosch F8DC4's with new Bosch plugs 09-386. Ended up leaving the car at the dealer. Initial results show that the plugs, wires, and coils are all fine. Engine is running very rich which is causing the rough idle. It was running fine before changing the plugs and wires!!! The dealer will begin again on Monday; hopefully they can determine the exact cause; rather than replacing most everything under the hood!! Any suggestions? Thanks.
