I've been trying to get my fuel pressure set correctly, but my oxygen sensor isn't any help. My sensor voltage reading is .910-.920mV at WOT. I can increase or decrease my fuel pressure and the reading never changes. I'm not sure what the problem is, but the oxygen sensor is only about 2 months old. If anyone has any ideas any help would be appreiciated.

 

Ive seen this problem before

check your throttle position sensor, ill bet its not going past 4 volts WOT. You can make it adjustable if its not allready by enlarging the bolt holes through it (a round file does it) Keep the idle volts under 1.25
ideally just keep it around .7-.9 and be sure it goes past 4 volts and its a steady sweep

this actually was what happened to jesters RS when he was still tbi when i first met him

 

Well, I've checked my TPS and I don't think that is the problem. My idle voltage is .74 and WOT is 4.26. The reading climbs steadily as the throttle is opened. Any other ideas?

 

now you have me stumped

so nothing you with the fuel pressure changes your wot O2 reading huh?

hmmmm

 

If you overtightened the O2 sensor, it can sometimes read high. Also, contamination of the sensor from incorrect gasket sealers/silicone/Permatex can cause permanent high readings... I'm assuming that your o2 readings are around .45-.5 volts in closed-loop so my thoughts may mean nothing, I guess... Blocked regulator return line can cause high fuel content but not usually in WOT... hmmmmmmmmmmm