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Q: Doesn't start when warm - 1974 Mercedes Benz 240D

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My car wasn’t running for quite a while, but I finally got the money to take it to the mechanic to get it fixed. I went to get the car and started it and it had 3 bad glow plugs which caused a loud hammering noise. The person that owned the car before me told me it had injector knock. The mechanic is sending them out to be tested. Well the car didn’t get fixed very well and it doesn’t start very well now when it’s warm. It has to cool back down again before it can be started without a problem. Do you know what could be causing the starting problem?

Hello. It sounds like the injectors and the glow plugs need to be replaced. The cold start valve could have a problem as well. This valve could be kicking in when it shouldn’t (when it’s warm) and this may result in a hard-to-start condition. Have a certified technician, like one from YourMechanic, diagnose the hard-start and help proceed with the correct repairs.

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