W203 Shaking very rough on idle, drives fine. No CEL.
10-19-2018, 08:44 AM
#1
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W203 Shaking very rough on idle, drives fine. No CEL.
EDIT: MOD please move to W203 
too used to coming into the W204 forum lol.
Hey guys need some help,
I've been working on my mothers' car recently a 2005 C240 with 148k miles that had issues starting and when it did it was VERY rough on idle. I knew the starting issue was due to CPS because STAR was showing a CPS code even though the CPS was replaced 2 days prior with an Advance Auto Parts one. Ordered a Bosch one from FCPEuro and replaced it myself to make sure it was really done. The car starts fine now and no CPS code, but the car still idles extremely rough. Another thing I noticed is that it cranks a random amount of times before starting (Fuel issue?). Sometimes it starts right away, sometimes it cranks for 1-2seconds, totally random. The car had issues with the Fuel Pump in the last year twice and was replaced as well with an Auto Parts one. STAR shows no codes at this point besides F-SAM solder issue which affects turn signals and bad stepper motors.
Since no CEL with lean/rich codes, misfire or evap leaks, it is safe to assume this is not a vacuum leak, or electric related. Is the Auto Parts pump going to crap already? Would there be STAR codes for fuel issues?
Any insight? Maybe procedures to test certain systems with STAR like the fuel pump?
Thanks.
too used to coming into the W204 forum lol.Hey guys need some help,
I've been working on my mothers' car recently a 2005 C240 with 148k miles that had issues starting and when it did it was VERY rough on idle. I knew the starting issue was due to CPS because STAR was showing a CPS code even though the CPS was replaced 2 days prior with an Advance Auto Parts one. Ordered a Bosch one from FCPEuro and replaced it myself to make sure it was really done. The car starts fine now and no CPS code, but the car still idles extremely rough. Another thing I noticed is that it cranks a random amount of times before starting (Fuel issue?). Sometimes it starts right away, sometimes it cranks for 1-2seconds, totally random. The car had issues with the Fuel Pump in the last year twice and was replaced as well with an Auto Parts one. STAR shows no codes at this point besides F-SAM solder issue which affects turn signals and bad stepper motors.
Since no CEL with lean/rich codes, misfire or evap leaks, it is safe to assume this is not a vacuum leak, or electric related. Is the Auto Parts pump going to crap already? Would there be STAR codes for fuel issues?
Any insight? Maybe procedures to test certain systems with STAR like the fuel pump?
Thanks.
Last edited by xEryx; 10-19-2018 at 08:50 AM.
