Rough idle

SwedeN95 GT

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1998 GT has a rough idle aswell as jerky acceleration at times and sometimes just turns off completely when stopped or slowing down.

Engine code says Bank 1 and 2 running too lean.

Anyone knows what it might be?
 

07GtS197

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Clean the maf, it can cause erratic idle like that. Also check for vacuum leaks and check fuel pressure. Whatever the issue is, is affecting both banks. Could also be a failing fuel pump.
 

96blak54

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Some cold air intakes, not factory maf housings, or air filters on the maf will cause running problems but im leaning towards a fuel pump issue like @07GtS197 stated. Gotta get a fuel gauge on the fuel rail to test pressures. That would be a good place to start
 

BLKHAWK611

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Clean the maf, it can cause erratic idle like that. Also check for vacuum leaks and check fuel pressure. Whatever the issue is, is affecting both banks. Could also be a failing fuel pump.
I had same problem. I changed out the MAF sensor with good one (Borg Warner) and it fixed the problem. Then check timing and all problems were solved.
 

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