Hi, im having problems with my ecu 0135451732. Misfires cylinders 5 and 2.. bought used ecu 0175453232 which is supposed to be compatible. With the second one now it misfires 6 and 1. Could you pls help me.. should i try to get a used ecu with same part #, did I have to program the second one I purchased? Should i try your fix or send it somewhere to get it fixed, do i need to replace all coils? Its a w124 1993 300e.. its been sitting for a month…thank you guys!!
W124 misfires.. possible ecu
- Thread starter Josearey
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- Portsmouth, Hampshire.
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- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
Start from the beginning. What is causing the missfire? A poor spark, poor fuel pressure, lack of compression?
Thanks for your quick reply, I took the car to the car shop and they used a pulse reader, with the car's ECU (0135451732) no pulse in cylinders 5 and 2. With eBay's ecu 0175453232 no pulse in cylinders 6 and 1. They changed the coils from position too, same result. They say the misfires are caused by the ECU. I read a post here from grober where he shows how to fix the ECU by changing three transistors. The problem is here in Colombia there is no place to have the ECU properly checked.
Found another ECU on Ebay with my same part number.. could the second ECU not be working because of compatibility or programming issues. The car does not have an infrared key.
Found another ECU on Ebay with my same part number.. could the second ECU not be working because of compatibility or programming issues. The car does not have an infrared key.
- Joined
- Feb 8, 2007
- Messages
- 20,528
- Location
- Portsmouth, Hampshire.
- Car
- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
Can you send your ECU to a repair shop in the UK or US?
I can send it to USA... but don't know where to send it...
- Joined
- Feb 8, 2007
- Messages
- 20,528
- Location
- Portsmouth, Hampshire.
- Car
- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
Google ECU repair shops.
- Joined
- Feb 8, 2007
- Messages
- 20,528
- Location
- Portsmouth, Hampshire.
- Car
- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
Who knows.
Stratman
MB Enthusiast
Something you said in post #3 had me thinking. "Change three transistors" hints to me that each transistor serves two cylinders with the redundant spark system, where each cylinder gets two sparks per full four stroke cycle with the redundant one on the exhaust stroke. It saves production costs (three instead of six firing circuits) and takes up less space which was useful on my old motor bikes that used it. I don't know the firing order of your particular engine but I wouldn't be at all surprised to find that 2 and 5, and 1 and 6 are at opposite sides of the four stroke cycle, one of them at ignition while the other is at exhaust.
All this rambling means the ECU you bought from ebay may also be faulty, just on a different pair of cylinders. If you're handy with a soldering iron you could remove the faulty output transistor from one ECU and replace it with a good one from the other.
All this rambling means the ECU you bought from ebay may also be faulty, just on a different pair of cylinders. If you're handy with a soldering iron you could remove the faulty output transistor from one ECU and replace it with a good one from the other.
