LOW IDLE
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Joined: May 2024
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1997 benz w210 e230
LOW IDLE
I have a 1997 e230. Problem is low idle when in gear... right below 5. Ive already change the following :
Fuel pump
Fuel filter
ignition coil , cable, suppresor
spark plugs
Cleaned and checked the following
ECU, k40 relay, engine harness
Throttle body
Leak test
Maf sensor
Fuel regulator
Injectors
Scan the engine like 10x
No error on engine but all the mechanics cant figured it out. Any suggestions would be highly appreaciated
Fuel pump
Fuel filter
ignition coil , cable, suppresor
spark plugs
Cleaned and checked the following
ECU, k40 relay, engine harness
Throttle body
Leak test
Maf sensor
Fuel regulator
Injectors
Scan the engine like 10x
No error on engine but all the mechanics cant figured it out. Any suggestions would be highly appreaciated
Last edited by Alvin1944; May 16, 2024 at 05:28 AM.
Member
Joined: Jun 2023
Posts: 178
Likes: 45
2000 E320
Whenever you have low idle problem, first thing I suspect is vacuum leak somewhere. But that usually show up on CEL or while scanning. Easy test that you can do is get yourself a old school carb cleaner. Yes, carb cleaner. Shoot the engine with it. Do one area at a time, such as front of engine, front right, rear right, then go to left side and................You got the idea. If you notice a rpm drop, then you found the area to look. If no change, do a smaller areas. Still no change, you got us stomped.
One more area I can think of, is have you checked the intake tube? Not on MB, but I once helped my neighbor's Beemer and intake tube had small crack that was enough to have rough idle and didn't show up on scan. I forgot how old that Beemer was as it wasn't my car and I was just helping out. Replaced the tube and was all good to go.
And this should be somewhat shouldn't apply to our car or I should say more modern cars, but I once looked at pretty old pick up truck with rough idle. What was wrong with this truck was that most of the electrical connectors were all corroded with that green stuff and wasn't sending correct signals to ECU. Got some good connectors from donor car from junkyard and it was all good to go. But like I said, this shouldn't apply to more modern vehicles as most of the connectors, if not all, are weatherproof connectors now.
One more area I can think of, is have you checked the intake tube? Not on MB, but I once helped my neighbor's Beemer and intake tube had small crack that was enough to have rough idle and didn't show up on scan. I forgot how old that Beemer was as it wasn't my car and I was just helping out. Replaced the tube and was all good to go.
And this should be somewhat shouldn't apply to our car or I should say more modern cars, but I once looked at pretty old pick up truck with rough idle. What was wrong with this truck was that most of the electrical connectors were all corroded with that green stuff and wasn't sending correct signals to ECU. Got some good connectors from donor car from junkyard and it was all good to go. But like I said, this shouldn't apply to more modern vehicles as most of the connectors, if not all, are weatherproof connectors now.
