Isuzu Repair: Severe Hesitation when accelerating, fuel injection system, isuzu pickup

Question
QUESTION: I have a 1995 Isuzu pickup, 2.3l FI engine which hesitates severely upon anything more than slight acceleration. Idles well, check engine light comes on with rough engine performance. I have replaced timing belt, plugs and plug wires... still needs ignition timing after I find where I put my 20 year old timing gun! Help please...

ANSWER: Well I would suspect the EGR valve or fuel pump/system to be the culprit Jeff. Sorry for the delay as my computer messed up.

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QUESTION: Daniel,

I submitted a high rating for you. When you mention fuel pump/system, could this be as simple as FI cleaning or are we talking possible replacement. This is frustrating because I've never had a problem with it before and now it seems nothing I do fixes the problem. Thanks.

Answer
It could be something as simple as a plugged fuel filter(do to ethanol mixed with gas) or something as serious as a fuel pump replacement or fuel injectors Jeff. I would start by having a fuel injection system cleaned as well as a fuel pressure check done or check the voltage that the fuel pump has when energized okay? Let me know if you need anything else.