W204 C300 Cranks but has issue starting
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w204 Mercedes c300
W204 C300 Cranks but has issue starting
My 2008 c300 will crank and start but shut off immediately after starting. If I try a few times, let it rest a few minutes and come back it will usually start and when it does start it drives perfectly with no lights, codes, noises or hiccups. I’ve replaced the passenger side fuel pump, crankshaft position sensor, mass air flow sensor, key fob batteries, main battery, and all relays in the engine compartment fuse box. (All MB parts except BOSCH MAF). It will crank, make a split second of exhaust noise as if it’s started up then cut off immediately. The fuel pressure reads good, new battery holds full charge and I’ve run 2 cans of seafoam through 2 tanks of gas and the problem persists. I can’t afford to go to the mechanic but can buy and fix just about anything with the tools I have I need a diagnosis please!!
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Joined: Nov 2008
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From: SA
2008 C350-Sport-AMG-Active Agility Pack(Not reliable) +Izuzu KB6 3L(It seems Reliable)+Mazda
See if it has an overvoltage relay-? I will go over the coil wirings see if theres anything suspicious. How did it start happening, after which trip or incident if you can remember-?
Last edited by Moto_Guzzi; Aug 10, 2020 at 12:21 PM.
Thread Starter
Newbie
Joined: Jun 2020
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w204 Mercedes c300
I’ve replaced all relays in the engine compartment fuse box
I remember it not starting on the first try for the first time when leaving the house and stopping at a gas station to grab a drink, when leaving it took 4 tries to start
Thread Starter
Newbie
Joined: Jun 2020
Posts: 4
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w204 Mercedes c300
I’ve replaced the fuel pump and fuel pressure holds
. The fuel pressure checks around 50 and holds after cutting off the engine. Also once I get it started I can drive it for however long without cutting it off without hiccups. Also it started first try everyday for about a month then started having the recurring starting issue again
