A leaness can cause a hesitation, but would be noticebale as being a lazy feeling engine, oddly enough the uk like things rich for power, but the yanks have a saying lean is mean, they do the opposite!
The screws are a sod to get to whilst on the car, esp as they are usulaluy silly tight, but easy to take of the tb, loosen the screws, adn turn it in the opposite direction of travel, ie so it has more pre load resistance.
Get that pump rewired, as it will alter the fuelling as you drive, when under load if the current and voltage decrease this will slow the pump.
tabetha
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