GL diesel no start in cold temps
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CLK55amg CL600Renntech GL320BT
GL diesel no start in cold temps
First post here.I have a GL that is randomly not starting especially in cold temps. I scanned it. It has good rail pressure as well as good low pressure numbers @ 69.5 psi and it is is syncing just not starting. I have no codes, no abnormal issues. Just a no start when cold as well as a random no start when warm. Upon cold cranking Rpm was 130 up to 140. So I replaced the glow plug control module, new fuel filter and AGM battery. It warmed up weather wise and the cranking speed went up to 170’s still no fire so I hit it with a tiny shot of ether and it busted right off and ran perfect as usual. Motor ran for hours then upon shut off it didn’t restart. So I plugged the scanner back in to check cranking rpm it never went above 170’s so I let it sit for about 30 minutes and came back to it and had it cranking rpm in the upper 190’s and started right up repeatedly each attempt cranking rpm was in the upper 190’s to 205+… so question is, is the firing sequence to injectors contingent upon cranking rpm? This issue is literally running me ragged. No codes nada… everyone I speak with says change your glow plugs or injectors, fuel pumps etc….opinions???
Last edited by clk55AMG/CL600; Mar 13, 2022 at 11:43 AM.
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CLK55amg CL600Renntech GL320BT
Yes, the crank sensor is synchronizing with the cam sensor upon the start sequence.
The battery is a new AGM with 900 cca…. Voltage with this battery and the last Interstate AGM MTX is about a volt apart upon cranking the new one drops to 10.6 volts under cranking load.
The battery is a new AGM with 900 cca…. Voltage with this battery and the last Interstate AGM MTX is about a volt apart upon cranking the new one drops to 10.6 volts under cranking load.
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From: Allentown, PA
'08 GL 320 CDI
900a at 32*F? Or 900 at 0*F? Just double checking that's it's CCA you're reporting, not CA. 900CCA is quite good. It should be spinning faster. I've never done it on this particular vehicle, but can you run a jumper cable of some sort from the battery post in the engine bay to the starter? That will bypass the existing cable in case it's corroded - this is just to "verify" of course. Second thing I'd be looking at are the grounds.
Try this, though... do a multiple glow cycle. Hit the start button two times to activate the plugs, but keep your foot OFF the pedal so the engine doesn't start. Count to ten, then turn the engine off and do it again. Do that a few times then try starting.
Try this, though... do a multiple glow cycle. Hit the start button two times to activate the plugs, but keep your foot OFF the pedal so the engine doesn't start. Count to ten, then turn the engine off and do it again. Do that a few times then try starting.
Last edited by DennisG01; Apr 26, 2022 at 11:43 PM.
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CLK55amg CL600Renntech GL320BT
An update:
After pretty much testing and going through the schematics of various starting requirements and replacing the battery, control module etc. Everything checked good and I found the problem. It seems that the computer is looking for up to and over 200 rpm for a successful start event. If it doesn't happen initially it will crank until there is enough heat to combust the fuel. In my case the cure was a new starter. It now fires every time within 1.5 seconds with rpm in the low 200's. I can now enjoy turning it off without thinking I might have to breakout the Ether lol. Thanks for all the input.
After pretty much testing and going through the schematics of various starting requirements and replacing the battery, control module etc. Everything checked good and I found the problem. It seems that the computer is looking for up to and over 200 rpm for a successful start event. If it doesn't happen initially it will crank until there is enough heat to combust the fuel. In my case the cure was a new starter. It now fires every time within 1.5 seconds with rpm in the low 200's. I can now enjoy turning it off without thinking I might have to breakout the Ether lol. Thanks for all the input.
