1993 190e 2.6 low idle and dies when slowing
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1993 Mercedes 190e 2.6 5-speed
1993 190e 2.6 low idle and dies when slowing
Hello everyone, my 93’ 190e 2.6 Manual has a low idle and when I slow down for a red light etc. it dies on me. It starts right back up and is fine afterwards but it’s very annoying. It also will randomly start revving on its own up to about 2k rpm, if I blip the throttle it will drop back down to almost 0 then it sits at 400-500 rpm. This all happens whether it’s cold or after a long drive, engine temperature does not affect this issue. If anyone has any idea what this problem might be, i’d really appreciate some help. Thank you. (attached is a video of the high revving and throttle blip)
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1991 190E 2.3
Check all of your various hoses to make sure that they're in good shape and nothing is leaking because rubber deteriorates over time. Also check all of your engine wiring to make sure that none of the wiring is frayed or loose. Make sure that all of the wiring connections are nice and clean. All of these simple things might cause your symptoms. You might also want to check and make sure that your fuels filter and fuel lines are clear. It's also possible that the spark plugs may need to be replaced. Rule out all of these simple things first. If they all check out then that means that your problem might be more serious. Also, you never want to pump the throttle on a fuel injected car because it can flood the engine.
Last edited by 190Efan; Jun 23, 2025 at 12:03 AM.
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
I would take these steps:
(1) Measure your voltage at the X11 round diagnosis for your OVP voltage output. Make sure you have system voltage there and is steady. Your ABS light is on so I'm not sure if you have OVP issues
(2) unplug the IACV first. The idle will go up to 1100 - 1500 rpm when warm. See if the idle is high but steady. You just broke the closed loop idle operation. If it is steady, your idle control loop needs more diagnosis.
(3) If the idle is not steady and is still jumping up and down, you need to start diagnosis of your emissions system. First step is to also unplug EHA plug (in addition to the IACV plug). Tell us what happens. With this first emissions loop. Idle should remain high (different value then before) but stable.
Let us know what you found out from steps 1-3 above, We can go on from there.
(1) Measure your voltage at the X11 round diagnosis for your OVP voltage output. Make sure you have system voltage there and is steady. Your ABS light is on so I'm not sure if you have OVP issues
(2) unplug the IACV first. The idle will go up to 1100 - 1500 rpm when warm. See if the idle is high but steady. You just broke the closed loop idle operation. If it is steady, your idle control loop needs more diagnosis.
(3) If the idle is not steady and is still jumping up and down, you need to start diagnosis of your emissions system. First step is to also unplug EHA plug (in addition to the IACV plug). Tell us what happens. With this first emissions loop. Idle should remain high (different value then before) but stable.
Let us know what you found out from steps 1-3 above, We can go on from there.
