Hesitation, Stumble, and small backfire during acceleration at passing speeds.

[Jrh2345]

So I have this 1998 Chevy Tahoe I have been chasing this problem for about a week now. Let me first start by saying. My fuel filter is fairly new, spark plugs, wires, distributor cap and rotor are new. With all these new items I'm still having the problem. I connect the Modis and notice the MAF is reading high then normal, so I clean MAF and get no difference. Bought new MAF and symptom has gotten better but still has the problem. I believe the fuel pressure should be 60psi @ idle I think. Just tested pressure and I'm at 50psi @ idle and I have a P0161 (bank 2 sensor 2). The code I'm really don't think would cause this problem, will the fuel pump being 10psi low cause this much.

 

[lesterl]

P0161 is Bank 2 Sensor 2 heater circuit, this is just a "is the catalytic converter alive" sensor AFAIK. I wouldnt worry about it too much.

Fuel pressure low @ Idle would bother me, try blipping the throttle and see what it goes to, I would suspect maybe your pump is on its way out, if you do replace it, use an OEM pump assembly, dont get one of the generic parts store pumps.....

Good luck.