'97 E420 Multiple codes, runs very bad!
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'97 E420 Multiple codes, runs very bad!
Friday, my '97 E420 (102,000 miles) immediately started running rough on the way to work. I checked the codes and had 5. No codes were present immediately before this.
Here are the codes: P0303 (twice - Cyl. 3 misfire), P0432 (Left TWC), P0455 (Evap System - large leak), and P0300 (random misfire).
This indicates a misfire at cylinder three.
Any ideas on what would cause all these codes to pop up?
Thanks for the help!
Here are the codes: P0303 (twice - Cyl. 3 misfire), P0432 (Left TWC), P0455 (Evap System - large leak), and P0300 (random misfire).
This indicates a misfire at cylinder three.
Any ideas on what would cause all these codes to pop up?
Thanks for the help!
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Joined: Sep 2007
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1997 Mercedes Benz E420
First things to check...
make sure all vacuum line are intact, a large vac leak can lean out the mixture, causing all sorts of problems. Secondly, and this is a common problem with E420's with high miles, I would suspect a bad coil pack. As an experiment, swap the coil pack in question with #2, or #4, clear the codes and see if me misfire moves.
I had one coil pack that was failing on my E420 [with quite a few less miles than yours...] which triggered a bunch of "sympathetic" error codes being thrown; I suspect that it was shorting internally and was back feeding to the ECU and giving the processor fits... The local dealer/"stealer" states that if they find two bad coil packs on an engine, they replace them all as a matter of course.
Let us know how you make out.
JR
I had one coil pack that was failing on my E420 [with quite a few less miles than yours...] which triggered a bunch of "sympathetic" error codes being thrown; I suspect that it was shorting internally and was back feeding to the ECU and giving the processor fits... The local dealer/"stealer" states that if they find two bad coil packs on an engine, they replace them all as a matter of course.
Let us know how you make out.
JR
