car runs fine at elevations approx. less then 3500'. At higher elevations,car acts like not sufficient fuel. I need to kick down throwtle to get the acceleration boost. Could it be a fuel system pressure or control pressure problem? What should they be for this engine?

What year wagon?

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

Actually, at high altitudes it's the air density, not fuel pressure that's causing the anemic performance.

I cruised around in a turbo Conquest in Colorado Springs one year, and the boost would barely reach 3psi at full throttle.

Brought it back to Texas and WHOOOSSSHHHH!!!! Easy 7psi everytime!

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

On the 1988/89 wagons there is an altitude baro sensor that LEANS out the fuel mixture at altitude! LEAN = lower HP.
ON the 1990-92 wagons that is done by info exchange from the ignition system. However at altitude the engine still runs leaner & therefore less HP.

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. . . The 5000-foot elevation made it hard for my cars to "breathe." Noticed it first with my golden Olds, and then in the 280CE and the 420SEL. When I brought the 420 back down to Louisiana (and parts of NO are *below* sea level, BTW), it became a ball of fire.

(Though I got better gas mileage in Denver than in NO, part of which I attribute to better roads and longer distances between stoplights.)

__________________
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-- Paul W. (The Benzadmiral)
('03 Buick Park Avenue, charcoal/cream)
Formerly:
'97 C230, smoke silver/parchment; '86 420SEL, anthracite/light grey; '84 280CE (W123), dark blue/palomino

the extreme performance loss is only partially due to the increased altitude. I drive in the mtns a lot, so know what is reasonable.
I'm thinking the altitude sensor is over correcting. Engine runs strong at normal conditions & all cylinders have 190 psi

Back to the 300TE owner who is having poor performance at elevations over 3500ft. We drive our '93 300TE 4Matic west every winter to ski. We have driven over MANY mountain passes at elevations approaching and over 10,000ft. The car does not have quite the same performance as lower elevations but it is still acceptable. We normally live at sea level so we would notice any big difference. Your problem has to be something other than lower oxygen content in the higher elevation air.
srharvey
'82 380 SL 160M
'83 240D 240M
'93 300TE 4Matic 260M