C36 Starting Problem: OVP, CPS, Wiring Harness are OK; whatelse??

[kreeone]

Hello,

My 96 C36 with 75k + miles currently have a problem starting and I can’t seem to find an answer (fix) by searching the forums for previous posts; only recommendation of what I can do.

Problem: When starting the car, it would take at least 3 to 4 cranks before it would turn over. Once it starts, however, and within minutes of shutting it off, it will start again with no problems. But if I let it stand 10 – 30 minutes, the car would require 3 to 4 cranks again before it would start back up.

The car also performs as it normally would when it starts; no loss of power, no erratic idling, No CEL, and or anything out of the ordinary.

Forum Recommendations: Bad Over Voltage Protection Relay (OVP) as it is common to go bad. I replaced this and the problem did not go away. Check bad fuses and relays.

Next Step: I gave up and went to the dealer for them to diagnose and fix. The dealer had my car for over two weeks and was not able to re-create and diagnose the problem – they think I’m making it up. They said they performed the following checks: Electrical short, OVP, Wiring Harness, Gas (water; bad tank from gas station), Clogged Fuel Rail, Crank Positioning Sensor (CPS), and blown Fuse/Relay, Spark Plugs, Coils, and found nothing. With the chance to potentially charge me a significant amount of money for any of these services, they didn’t find anything wrong with the car, but once I got the car back I still had starting problems. I escaped without paying a dime for the diagnostic services and I was provided with a 2011 C300 as a loaner for two weeks – not bad.

I am looking for some feedback from C36/W202 owners and mechanics that have experience with the same symptoms.

Thanks!