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  #1  
Old 08-26-2008, 04:18 PM
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Running slower at WOT?

I recently did some EHA valve adjustments (swapping units, turning adjustments), and i've eliminated the problem of running too lean. Have i introduced the problem of running too rich now?

My car goes pretty quick now when I am not on WOT, but when I go WOT, the car feels slow. I let off a tiny bit and the car accelerates harder. what exactly happens when I go to WOT? is the EHA valve doing its job there or what?

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Old 08-26-2008, 08:25 PM
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When was the O2 replaced last?

Jonathan
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Old 08-26-2008, 08:57 PM
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O2 sensor was replaced within this year
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Old 08-26-2008, 09:24 PM
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Test your TPS on the side of the CIS metering plate?

Jonathan
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Jonathan Hodgman
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Enthusiast Service, Restoration & Tuning.
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Located in the Atlanta area
Specializing in all pre and post merger AMG's including Hammers and DOHC M117 engines.
Mercedes Repair Atlanta
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  #5  
Old 08-27-2008, 12:01 AM
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im pretty sure that the throttle position switch works if my car slows down at WOT but picks up if i let off the gas.

i did some testing today on the CIS and here are the results

duty cycle @ idle: ~50%
duty cycle @ 2500rpm: ~70%

O2 @ WOT: ~ 0.200v

all signs which point to the fact that my engine is probably unning a little lean at WOT.

the O2 sensor definitely works just fine. When I am at WOT, the sensor reads close to a constant 0.2v, and when I let off a tiny bit and feel the surge, the O2 sensor voltage starts jumping around again.

q: the engine is supposed to goto an open loop mode during WOT correct? is that why the voltages arent jumping around and my car goes slow?

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