Stalled 124 300E Help
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1992 300E
Stalled 124 300E Help
My daughter and my 1992 124 300E was running and died. Took it to an Indy in Washington State. They "think it is crank position sensor and they fail on these models.", however it started for them and could not make it die. I'm 2000 miles away. I normally do my own wrenching. New fuel pumps and filter a few months ago. Less than 80K miles. Can this sensor be diagnosed on a scope?
Other possibilities? Thank you in advance for any and all thoughts.
Other possibilities? Thank you in advance for any and all thoughts.
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'99 and '05 E55 AMG
Inexpensive repair as far as parts. CPS and fuel pump relay to cover both bases OEM (not Amazon) for CPS.
If car fails again, gonna have to dig deeper. Time to discuss failure scenarios with the offspring so she can be prepared just in case while on the road. Been there, done that, got the T-shirt...
If car fails again, gonna have to dig deeper. Time to discuss failure scenarios with the offspring so she can be prepared just in case while on the road. Been there, done that, got the T-shirt...
Thread Starter
Junior Member
Joined: Feb 2011
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1992 300E
bbirdwell, thank you. The car had been stored for 3 months. I had stalling issues prior to installing new fuel pumps and filter. After ran fine with no issues. I blamed the
ethanol fuel messing with the fuel pumps due to moisture and 3 to 4 month storage for the prior problem. Now not so sure. I should hear from the repair shop tomorrow. Will post results. If the CPS is the problem, cost is minimal. Handy930
ethanol fuel messing with the fuel pumps due to moisture and 3 to 4 month storage for the prior problem. Now not so sure. I should hear from the repair shop tomorrow. Will post results. If the CPS is the problem, cost is minimal. Handy930
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As mentioned above... CPS and fuel relay is a reasonable starting point that is worth firing the parts cannon at to rule them out.
If it continues to stall next up is applying smoke to the intake to find the false air leak. Your Indy shop should have the tool to do it.
If it continues to stall next up is applying smoke to the intake to find the false air leak. Your Indy shop should have the tool to do it.
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190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
It is difficult to diagnose something like this remotely and with very little data. You said it "died".
(1)Only once? while in Washington
(2)Does it keep dying.
(3)Is it hard to start after the stall?
(4) What is the mileage on the car?
(5) Was the engine struggling before the stall? Did it feel like fuel starvation, idle control or ignition. They all have different symptoms.
(6) Is the CPS resistance in spec?
(7) CPS failures generally show up when the engine is hot and it will refuse to restart until it cools down, do you have this case? It is not a typical weak link in the engine. My '89 at 210K miles is still the original.
Sounds electrical to me. Not necessarily ignition either. But we need more info.
Sudden stalls like this if the car restarts easily are generally OVP or ICV if the car just re-starts after the stall.
Yes you can test the CPS as well, but you will need an oscilloscope and just observe the HT timing signal going to the EZL, ignition control unit. It is available at the X11 diagnostic socket.
(1)Only once? while in Washington
(2)Does it keep dying.
(3)Is it hard to start after the stall?
(4) What is the mileage on the car?
(5) Was the engine struggling before the stall? Did it feel like fuel starvation, idle control or ignition. They all have different symptoms.
(6) Is the CPS resistance in spec?
(7) CPS failures generally show up when the engine is hot and it will refuse to restart until it cools down, do you have this case? It is not a typical weak link in the engine. My '89 at 210K miles is still the original.
Sounds electrical to me. Not necessarily ignition either. But we need more info.
Sudden stalls like this if the car restarts easily are generally OVP or ICV if the car just re-starts after the stall.
Yes you can test the CPS as well, but you will need an oscilloscope and just observe the HT timing signal going to the EZL, ignition control unit. It is available at the X11 diagnostic socket.
