Hi, just finished changing the water pump, belt, idlers, tensioner, and hoses. Also replaced the manifold pressure sensor (again). When I started the engine for post-repair checks, I found CHECK ENGINE illuminated. Whipped out the trusty OBD II scanner and found 1 code: P0069 manifold absolute pressure barometric pressure correlation.
I erased the code but it resets as soon as the key is on and before the engine starts.
I had to remove the air filter box and turbo inlet elbow duct and unplug the involved harness to change the water pump so I figured one of these is not making contact. I checked and they appear to be fine. Can anyone guide me here?
Water pump and associated repairs seem fine btw.

__________________
Providing a home for these cars:
1951 Buick Special De Luxe
1977 Rolls-Royce Silver Wraith II
1970 Rolls-Royce Silver Shadow
1986 Mercedes-Benz 420 SEL
2005 Mercedes-Benz E 320 CDI
2012 GMC Sierra 1500 4X4
1927 Pierce-Arrow Series 80
1931 Pierce-Arrow Series 43
1926 Ford Model T coupe

Is the hose connected to the MAP sensor? Maybe the hose is degraded.

Sixto
98 E320 sedan and wagon

Hose is connected and seems in fine condition. Also, as the code sets before the engine is started, I suspect harness/connector/ end device issue.

__________________
Providing a home for these cars:
1951 Buick Special De Luxe
1977 Rolls-Royce Silver Wraith II
1970 Rolls-Royce Silver Shadow
1986 Mercedes-Benz 420 SEL
2005 Mercedes-Benz E 320 CDI
2012 GMC Sierra 1500 4X4
1927 Pierce-Arrow Series 80
1931 Pierce-Arrow Series 43
1926 Ford Model T coupe

Recall that I changed the manifold pressore sensor. Perhaps the replacement sensor is wrong?

__________________
Providing a home for these cars:
1951 Buick Special De Luxe
1977 Rolls-Royce Silver Wraith II
1970 Rolls-Royce Silver Shadow
1986 Mercedes-Benz 420 SEL
2005 Mercedes-Benz E 320 CDI
2012 GMC Sierra 1500 4X4
1927 Pierce-Arrow Series 80
1931 Pierce-Arrow Series 43
1926 Ford Model T coupe

How long ago was the MAP sensor replaced? If it's been working before your water pump R&R, it's highly doubtful that it's the wrong part since you'd have had codes long before now.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

Sensor failed about 1 1/2 years ago so I replaced it. Failed again a couple weeks ago. I noticed the new one I installed (ordered fromPeach) was USA-made and had 1 digit different from the one I removed (Bosch). I think I have the wrong part.

__________________
Providing a home for these cars:
1951 Buick Special De Luxe
1977 Rolls-Royce Silver Wraith II
1970 Rolls-Royce Silver Shadow
1986 Mercedes-Benz 420 SEL
2005 Mercedes-Benz E 320 CDI
2012 GMC Sierra 1500 4X4
1927 Pierce-Arrow Series 80
1931 Pierce-Arrow Series 43
1926 Ford Model T coupe

Did it work after you replaced it though? Or is the light a recurring problem ever since replacing it? I ask because you may not have a sensor problem, you may have a wiring problem...

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

No, it has never worked; I replaced a failed sensor while I was replacing the water pump. I am convinced I got a sensor for a gasoline car by mistake so I have ordered another.

__________________
Providing a home for these cars:
1951 Buick Special De Luxe
1977 Rolls-Royce Silver Wraith II
1970 Rolls-Royce Silver Shadow
1986 Mercedes-Benz 420 SEL
2005 Mercedes-Benz E 320 CDI
2012 GMC Sierra 1500 4X4
1927 Pierce-Arrow Series 80
1931 Pierce-Arrow Series 43
1926 Ford Model T coupe