Odd behaviour and CEL
Thread Starter
Junior Member
Joined: Jul 2008
Posts: 38
Likes: 0
1993 400E
Odd behaviour and CEL
I recently acquired a 99 C230 kompressor, which has come up with an interesting issue.
Day 1: CEL comes on, no noticeable difference in performance. Go home, check it, p0170 (fuel trim malfunction bank 1) code, try to clear it, wont clear. Open gas cap, code clears (weird). Do some internet searching, almost order new MAF.
Day 2: car loses 95% of throttle (!!). Coast off of road, somehow make it home in rush hour traffic with only the first 5% of throttle working. Same OBDII code.
Day 3: car has issues with throttle again, I loosen gas cap, drive with loose cap, no more running issues, but after 15 min, CEL comes on and low fuel indicator flashes constantly (I assume this is the gas cap loose indication). Car drives fine.
This seems to me like it might be creating too much vacuum in the gas tank instead of being a MAF issue like this p0170 code always seems to otherwise indicate. I'm curious if you guys have any thoughts about this or have seen anything like this before. I don't really know how the gas tanks in the w202 vents, but I'll assume its something complicated and expensive.
Day 1: CEL comes on, no noticeable difference in performance. Go home, check it, p0170 (fuel trim malfunction bank 1) code, try to clear it, wont clear. Open gas cap, code clears (weird). Do some internet searching, almost order new MAF.
Day 2: car loses 95% of throttle (!!). Coast off of road, somehow make it home in rush hour traffic with only the first 5% of throttle working. Same OBDII code.
Day 3: car has issues with throttle again, I loosen gas cap, drive with loose cap, no more running issues, but after 15 min, CEL comes on and low fuel indicator flashes constantly (I assume this is the gas cap loose indication). Car drives fine.
This seems to me like it might be creating too much vacuum in the gas tank instead of being a MAF issue like this p0170 code always seems to otherwise indicate. I'm curious if you guys have any thoughts about this or have seen anything like this before. I don't really know how the gas tanks in the w202 vents, but I'll assume its something complicated and expensive.
Senior Member
Joined: Feb 2011
Posts: 366
Likes: 11
From: Australia
E63S
Have a 2015 E63, having just come from a 2013 C63. Initial impressions are that in S and S+ the transmission in the E is quite a bit livelier than the C63 ie wants to hold on to the lower gears, and reluctant to change up to the higher gears at all. Even when “cruising” in say S+ in the 40 - 60 mph range it will stay in say 4th, or 5th, ready to change up with even the slightest throttle prod. Quite different to the C63 I had, which is strange as I believe they both use the same transmission, or perhaps just different programming of shift points etc given different engine characteristics.
