New problem
Thread Starter
Super Member
Joined: Feb 2008
Posts: 844
Likes: 1
From: Orland Park, Illinois
1994 E320 (current)
New problem
Here are the symptoms
1994 E320
1. Has had rough Idle for a couple of months.
2. Mild Surging for the last couple of months. Mostly at stop lights and really bad in reverse. I replaced the MAS flow sensor and that cleaned it up a bit.
3. Recently at start up the car runs as though it has a dead cylinder or like the timing is way out of whack. If I sit at idle and rev the engine past 4000 rpm a couple of times then it will clear up. If you have ever had a catalytic converter collapse and the engine bogs down it feels just like that. If I floor it while it is screwing up it takes a couple of seconds and then it clears up.
My first thought is the OVP relay from what I have read and considering I replaced the MAS and have confirmed the Wire Harness to be replacement. Have any of you come across this and what was the culprit for you? I just don't want to go spend the $90.00 on the OVP if there is something else that is glaring. Let me know what ya know.
Thanks Guys
Gary
1994 E320
1. Has had rough Idle for a couple of months.
2. Mild Surging for the last couple of months. Mostly at stop lights and really bad in reverse. I replaced the MAS flow sensor and that cleaned it up a bit.
3. Recently at start up the car runs as though it has a dead cylinder or like the timing is way out of whack. If I sit at idle and rev the engine past 4000 rpm a couple of times then it will clear up. If you have ever had a catalytic converter collapse and the engine bogs down it feels just like that. If I floor it while it is screwing up it takes a couple of seconds and then it clears up.
My first thought is the OVP relay from what I have read and considering I replaced the MAS and have confirmed the Wire Harness to be replacement. Have any of you come across this and what was the culprit for you? I just don't want to go spend the $90.00 on the OVP if there is something else that is glaring. Let me know what ya know.
Thanks Guys
Gary
Thread Starter
Super Member
Joined: Feb 2008
Posts: 844
Likes: 1
From: Orland Park, Illinois
1994 E320 (current)
So I built my little code reader out of a plastic container an LED and some plugs (if you havn't done this yet you really should i should have done it sooner).
The codes are saying O2 Sensor (code 13) and Idle/accelerator controller (code 42) so I will start with the O2 and then go with the idle controller. I'll post how it goes
The codes are saying O2 Sensor (code 13) and Idle/accelerator controller (code 42) so I will start with the O2 and then go with the idle controller. I'll post how it goes
MBWorld Fanatic!
Joined: Dec 2006
Posts: 1,042
Likes: 1
From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
Sounds like it's running rich at startup. If it does it when it's cold I would suspect a temp sensor. The O2 sensor is not active until a couple minutes after a cold startup. If it only does it when warm then I would lean towards the O2 sensor. Since you are getting a code for that you should replace it anyway. Good luck, keep us posted.
Senior Member
Joined: Jun 2007
Posts: 266
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From: Cambridge, Ontario
95 E320 Coupe, Diesel Golf
Have you replaced your spark plug wire set??? I had teh same problems for months, replaced teh engine harness helped a little, then bought the new wire set, car runs like a champ now, knock on wood.
Thread Starter
Super Member
Joined: Feb 2008
Posts: 844
Likes: 1
From: Orland Park, Illinois
1994 E320 (current)
I just replaced plugs a month ago and thoroughly inspected the plug wires. They have been replaced recently and seem to be fine.
Thread Starter
Super Member
Joined: Feb 2008
Posts: 844
Likes: 1
From: Orland Park, Illinois
1994 E320 (current)
Sounds like it's running rich at startup. If it does it when it's cold I would suspect a temp sensor. The O2 sensor is not active until a couple minutes after a cold startup. If it only does it when warm then I would lean towards the O2 sensor. Since you are getting a code for that you should replace it anyway. Good luck, keep us posted.
MBWorld Fanatic!
Joined: Dec 2006
Posts: 1,042
Likes: 1
From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
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Thread Starter
Super Member
Joined: Feb 2008
Posts: 844
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From: Orland Park, Illinois
1994 E320 (current)
I found out it only has one. I guess back then they didn't have the really stringent California emissions standards (the same on that requires the Subaru STi to have 3 cats and 4 O2sensors.) I ran the second set of codes on pin 14and it is giving me a brake lamp switch code. I think the main problem is the O2 and I am going to replace it this week.
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Thread Starter
Super Member
Joined: Feb 2008
Posts: 844
Likes: 1
From: Orland Park, Illinois
1994 E320 (current)
MBWorld Fanatic!
Joined: Dec 2006
Posts: 1,042
Likes: 1
From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
