yet another E34 no Cold start thread! M50

[affende]

I'm pretty sure that the only diagnostic connectors with the connection to the starter are on M20 & M30 cars, those requiring valve adjustments.
Bentley diagrams still show it but I recall hearing the late cars don't have it. I'd love to be wrong.
Curious to hear from the OP on this.

93 E34 M50TU Auto US spec

Pin 11 on the diagnostic connector will spin the starter with +12 Volts

[affende]

Car is going bye bye ... if anyone local needs some parts, let me know.

[gc325is]

Sounds like you had spark problems in a few cylinders in the past and now it has gotten worse.
Maybe due to the excess oil in the cylinder fouling the plugs. How did you check for spark? Was it for all 6 ign coil packs?

I think the E36 has the same design Sorry I was looking for the engine temp sensor and read your problem. It's sad to hear the end of any BMW

[affende]

Sounds like you had spark problems in a few cylinders in the past and now it has gotten worse.
Maybe due to the excess oil in the cylinder fouling the plugs. How did you check for spark? Was it for all 6 ign coil packs?

I think the E36 has the same design Sorry I was looking for the engine temp sensor and read your problem. It's sad to hear the end of any BMW

I checked on a few coils with a spark tester, they jumped a half inch gap (last time i changed the plugs, with the engine running, i unplugged each coil to check if the stumble was cylinder spark related, it was not). Fouling is definitely a possibility, but going from a slight stumble (that has always been there, even with new plugs) to a complete no start condition seems improbable.

[squirrelhill]

Did you consider testing/replacing the blue coolant temp sensor (CTS) under the intake manifold? I stand to be corrected, but it is my understanding that a failed CTS can result in a no-start/flooding condition.

[affende]

Did you consider testing/replacing the blue coolant temp sensor (CTS) under the intake manifold? I stand to be corrected, but it is my understanding that a failed CTS can result in a no-start/flooding condition.

I did not. do you have info on it?

[affende]

Did you consider testing/replacing the blue coolant temp sensor (CTS) under the intake manifold? I stand to be corrected, but it is my understanding that a failed CTS can result in a no-start/flooding condition.

jumped the blue DME CTS plug with a resistor, no change.

[jrbogdovitz]

Im guessing you had 12v at the coil pack connector? Was it the blue one on CL for like 750? Im in Colorado too so i saw it on CL all the time. I just got done figuring out the same situation. Did you ever get a fuel pressure gauge?

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Look into the main relay if you have not already.

[affende]

Im guessing you had 12v at the coil pack connector? Was it the blue one on CL for like 750? Im in Colorado too so i saw it on CL all the time. I just got done figuring out the same situation. Did you ever get a fuel pressure gauge?

- - - Updated - - -

Look into the main relay if you have not already.

fuel pressure and main relay checked good. Had good spark on 3 cylinders ... didnt check the other 3.

yes it was that one for $750 ... but yours for $600

[summitp]

I didn't see how you checked fuel pressure, but those have a Schrader valve on the rail if I recall, you can check fuel pressure with a simple air pressure gauge. Have some one crank the engine while you check the pressure. Have a rag handy. Should be 3 Bar? I think.
A bad coolant temp sensor will cause not enough fuel. When cold, the coolant temp sensor tells the dme to provide extra fuel for a cold start. As the engine warms up the coolant temp sensor tells the engine to gradually lean out until operating temperature is reached. You can test the sensor by pulling it and checking resistance. Then put it in hot water with a thermometer, resistance should drop as the temp goes up.
The maf sensor tells the dme how much air is coming in to the motor so the dme know how much fuel to provide. Make sure the maf is plugged in.
With the throttle body closed, there is an idle control valve that is operated by the dme. Make sure plugs on those are all plugged in properly.
The crank position sensor can only be accurately checked with an oscilloscope, but a multimeter can give hint if it is good or not. Unplug it and hook up the ohm meter, you should see resistance rise and fall as the reference wheel spins. If you get no oscillation in resistance, then you have a bad sensor or the gap between the sensor and the wheel is too large.

[ross1]

Don't expect any updates, summitp, as it's all a moot point now, the OP has given up on the car and is currently offering it up for parts.