Not entirely sure...All I can tell you is when I very first bought my 260E the original EHA was causing me major bottom end power issues which were immediately resolved after swapping it even though the fuel pressure readings were within spec. So I can say from experience it absolutely has an effect on idle and acceleration enrichment.

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k