Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
1999 ford ranger 4.0l sohv p0 code 172 and 175
bank 1 and 2 long term trim -25
maf 4 -5.2 at hot idle
bank 1 and 2 o2 changing -4 to +5
shrt trim between .2 to .7 volt
orignal problem was exhaust leak bank 2 manifold gasket
replaced gasket and bank 2 sensor
The MAF reading seems to be rational, but can you provide us with a voltage reading? Just want to be double sure you're not chasing an input problem. I look for less than 1.0V, preferably closer to .9V.
Excessive fuel pressure is my next thought. Hoping someone with access to SI can back me up, but I remember 60 PSI being the magic number. Anything above 70 would be a red flag, IMO. Pretty sure these use a returnless system, so any excessive pressure is gonna be a problem at the pump itself.
Is the idle rough? Misfiring? If so, look at the DPFE voltage at idle. Over 1.1V is a problem, suggesting a stuck open EGR valve. If the idle is not rough, skip this and move on.
Finally, has anyone been doing engine repairs recently? I ask because there's a couple different injectors out there that will fit perfectly, but have significantly different flow rates. This usually happens during some kind of motor swap.
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