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Discussion Starter #1
Hi, Just bought this Coupe and it is wonderful until now. One day in some start and stop traffic, the car stalled out at idle. Car was towed back to my house. I tried starting again when I got home and it managed to start but it was very unsteady and died again soon after. After that, the car only cranks but does not start. Compression sounds. I was getting an cel which fuel trim bank 2 was lean and also air temperature sensor was giving high output. I replaced the MAF to no avail. I read up on another post saying it was the ECU but I would like to rule out that suspicion for now as it is beyond me. I suspected the CPS but the car would not start again even from a very cold start (snow covers car which has not started for weeks). Is the cps still a suspect? What other options could I explore? Thanks
 

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CPS failure does seem more common with extreme temps. What codes do you have?
 

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Discussion Starter #3
I am getting a po171 but I have forgotten the other code. I know the readout on my obd2 says the airflow temperature sensor was giving a overly high reading for the second code. I have replaced the MAF which was chocked with oil from the oil in intake issue trying to solve the no start.
 

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If you suspect the MAF sensor, you can unplug and try to start. If nothing else is wrong, the car should start and run, albeit with some error codes.
 

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Discussion Starter #5
I had already replaced to MAF. I did unplug and tried to start but there was no change. I am in the process of taking apart everything to get to the cps. Anyone got any instructions? Thanks
 

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I can't find WIS docs, but it's located on the rear of the engine, top left side (much like in the M112 engine).
 

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Discussion Starter #9
I pulled the CPS. Is there anyway to test if its actually broken? Mine had a slight twist to the metal tabs on the end that plugs to the wire. Is there anything fishy about this? Also mine was on the bottom right of the M111 engine. Definitely not where the m112 has it. :)
 

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Yeah, WIS docs on the older engines are not as detailed. I went by the parts diagram, which showed it top left, but the may be somewhat generic. I'm not sure if there is a way to test the CPS. For the price, it's probably worth replacing it - just get a genuine one or a Bosch from a reputable source (i.e. not Amazon/eBay).
 

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Discussion Starter #11
Well, it seems my Crankshaft position sensor change did not do anything. I am really unsure now of where to keep going. Again the car cranks but never starts. Any pointers appreciated :bowdown:
 

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Maybe it's a fuel related issue.
Check if you've got fuel pressure at the engine.
Is the tank empty?
Is the fuel filter ok?
Is the fuel pump working?
 

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Discussion Starter #13
There is definitly pressure in the fuel system because every time I press the schrader valve on the fuel rail after I turn key to pos 2 and then switch off, there is pressure forcing some fuel out of it. I still have 1/4 fuel in the tank.
 

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OK so if it's not fuel pressure,then next possibilities could be..
Low compression
Water in fuel
Defective ignition coil/s or ignition wiring connections
Clogged fuel injectors
Bad spark plug/s

Sorry I can't just tell you exactly what it is,maybe someone else has an idea?
 

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Thanks this is what I needed so I can continue to poke around the car.
Ideally the next thing would be to use an ignition tester to check for sufficient spark to fire the spark plugs.This is placed in between the coil and the plug.You disable the fuel system by pulling a fuse,then check each plug for spark while cranking.
If only one is bad then you suspect the coil or wiring to that plug.
If they are all bad,ie no spark/flash or intermittent on all cylinders,then you suspect the PCM,Powertrain Control Module.
If they all flash ok,check spark plugs for correct gap etc.
 

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Discussion Starter #17
Finally solved. The problem was excessive oil inside the the intakes which fouled the MAF sensor. I took off the oil separator assembly and poured a lot of oil out. I then replaced the MAF and the car ran immediately. It has been a couple months and car is running consistently. Thanks for all the help everyone provided.
 
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