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greenphant
02-14-2008, 06:56 AM
My C280 just started this strange problem the other day:
When it's at idle, either in park or in gear, the engine accellerates on its own. Especially in park, the RPMs will go down really low - almost to stall zone - and then shoot up to about 1500, and then go up and down and up and down. It drives fine as far as I can tell, but I don't want to be doing any damage to cause further problems.
It's almost like how old cars with carbuerators out of adjustment used to run funny - but obviously that's not the case here.
Anyone who can be of any help, please let me know
-G
Fred Hayward
02-14-2008, 02:23 PM
Originally posted by greenphant
My C280 just started this strange problem the other day:
When it's at idle, either in park or in gear, the engine accellerates on its own. Especially in park, the RPMs will go down really low - almost to stall zone - and then shoot up to about 1500, and then go up and down and up and down. It drives fine as far as I can tell, but I don't want to be doing any damage to cause further problems.
It's almost like how old cars with carbuerators out of adjustment used to run funny - but obviously that's not the case here.
Anyone who can be of any help, please let me know
-G I Think you'll find Its your VR module /relay
greenphant
02-14-2008, 05:30 PM
Originally posted by Fred Hayward
I Think you'll find Its your VR module /relay

VR Module/Relay? What does the VR stand for - I can't search on that part name. If it is an easy fix, I'll definitely replace it.
Please let me know
Fred Hayward
02-14-2008, 05:33 PM
Originally posted by greenphant
VR Module/Relay? What does the VR stand for - I can't search on that part name. If it is an easy fix, I'll definitely replace it.
Please let me know Voltage regulator
greenphant
02-14-2008, 05:36 PM
SWEET that's only a $26 part - where under the hood do I locate this?
-G
Fred Hayward
02-14-2008, 05:50 PM
Originally posted by greenphant
SWEET that's only a $26 part - where under the hood do I locate this?
-G Full name is ; The Over Voltage relay, It controls the ABS,Idle And other parts !Located Near ECU
greenphant
02-14-2008, 05:56 PM
Is this what you're referring to:

http://i100.photobucket.com/albums/m11/greenphant/vr_regulator.jpg

please let me know.
Fred Hayward
02-14-2008, 06:37 PM
Originally posted by greenphant
Is this what you're referring to:

http://i100.photobucket.com/albums/m11/greenphant/vr_regulator.jpg

please let me know. No ; Its a multi pronged Small square box with a Fuse under the lid !
greenphant
02-14-2008, 06:48 PM
Is this it?

http://i100.photobucket.com/albums/m11/greenphant/overloadrelay.jpg

They call it an "overload relay"
Fred Hayward
02-14-2008, 06:50 PM
Originally posted by greenphant
Is this it?

http://i100.photobucket.com/albums/m11/greenphant/overloadrelay.jpg

They call it an "overload relay" YES !!! It Can Cause many Problems !
strictlyspeakin
02-18-2008, 03:23 PM
did you try it to see if it worked?

do you notice that the rpm drop corresponds with the air pump or a/c kicking on?
greenphant
02-18-2008, 06:15 PM
Figured it out. I couldn't BELIEVE it was so simple.

2 step process:

1. Order Air Mass Sensor (MAF/MAS whatever you want to call it)

2. Install above sensor.

Done. 20 min project, including the phone call to order the part.

I got it for $215 from www.foreigncarpartsonline.com - OEM Bosch, didn't want to do any aftermarket crap. It instantly fixed the problem and the car runs VERY smoothly now.

I ordered that relay and I think I'll send it back, since it was $75. I'm also planning to do the fuel filter soon. Any tips on that?
-G