S550 going into some sort of limp mode?
05-22-2021, 10:13 PM
#1
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2007 s550
S550 going into some sort of limp mode?
Hello,
I have a 2007 MB s550. The car has started going into this sort of limp mode.. it still shifts through all the gears.. it will suddenly start missing and continues until it is shut off and left to sit for several minutes and then it runs perfectly fine. Never throws a code and It seems to occur mostly when I accelerate. Plugs and coil packs and air filters have all been changed. Any ideas? SOLVED! It was the mass air flow sensor intermittently working and not.
I have a 2007 MB s550. The car has started going into this sort of limp mode.. it still shifts through all the gears.. it will suddenly start missing and continues until it is shut off and left to sit for several minutes and then it runs perfectly fine. Never throws a code and It seems to occur mostly when I accelerate. Plugs and coil packs and air filters have all been changed. Any ideas? SOLVED! It was the mass air flow sensor intermittently working and not.
Last edited by Cowboyzion; 08-03-2021 at 12:37 PM. Reason: Forgot something
05-22-2021, 11:18 PM
#2
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Hello,
I have a 2007 MB s550. The car has started going into this sort of limp mode.. it still shifts through all the gears.. it will suddenly start missing and continues until it is shut off and left to sit for several minutes and then it runs perfectly fine. It seems to occur mostly when I accelerate. Plugs and coil packs and air filters have all been changed. Any ideas?
I have a 2007 MB s550. The car has started going into this sort of limp mode.. it still shifts through all the gears.. it will suddenly start missing and continues until it is shut off and left to sit for several minutes and then it runs perfectly fine. It seems to occur mostly when I accelerate. Plugs and coil packs and air filters have all been changed. Any ideas?
05-23-2021, 09:16 AM
#4
well might as well fit a new crank position sensor - CPS (easy home job from above and only $45, these fail all day long so even if its working today it will fail soon). I'd then double check what diagnostics I'm using, you say you did the coil packs, decent diagnostic kit will tell exactly which cyl was playing up, so if on that kit and finding nothing, maybe see what live data its reporting
just a thought, the misfire is all the time or when its moving? traction control will hold it back without a code and at that age if you haven't done all 4 ABS sensors they should have failed by now.... got any park brake oddities or extra audible bongs as you drive off? It can play up for 6 months with only park brake messages before the full on ESP message comes up
just a thought, the misfire is all the time or when its moving? traction control will hold it back without a code and at that age if you haven't done all 4 ABS sensors they should have failed by now.... got any park brake oddities or extra audible bongs as you drive off? It can play up for 6 months with only park brake messages before the full on ESP message comes up
05-26-2021, 11:15 AM
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SL55AMG, GL450, SLK, S550, Maserati Coupe
One possible cause is the gas pedal. It is an assembly and can be removed and replaced, they cost a little over $100 and are fairly easy to replace. It is a potentiometer and when they wear out it will send confusing signal to the ECU so it goes to limp mode, and returns to normal after shutdown and restart. My 2008 S550 would go to limp mode after I'd floored the gas pedal to pass someone, kind of embarrassing to lose power after passing. It did this a few times so I got a replacement, and doesn't do that any more. It's called an accelerator pedal, I bet that is the part causing the problem
