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171-fuel system at adaptive limit, HEGO unable to switch.
327-EVP or DPFE circuit below minimum voltage
332- insufficent egr flow
634-MLP sensor voltage out of self test, AC on.
Steps that have been taken:
have replaced egr valve, new fuel pressure regulator, replaced oxygen sensor.
i do not know what sensors they are speaking of with evp DPFE and MLP.
also have found a 2 wire plug broken and melted it looks like. I do not know where it leads, other f150 does not have this part of harness. the location of this plug can be traced back to the harness almost directly above the front engine lift point. any ideas as to what this is? i am still having an over fueling issue, still smells very rich. this could be related to code 171 is my thought. will be checking for new codes again in the evening or tomorrow.
634 CHECK MANUAL LEVER POSITION (MLP) SENSOR ALIGNMENT
Service Code 634 indicates the MLP sensor is out of Self-Test range when the gear selector is in PARK. Correct resistance range for this sensor is from 3770 to 4607 ohms.
Possible causes:
-- Misadjusted linkage.
-- Open or short in harness circuits.
-- Damaged MLP sensor.
-- Damaged processor.
Check the EGR Solenoid to see if it it is supplying vacuum to the EGR Valve. (this occurs during KOER testing and during increased rpm, but not at Idle or WOT)
If the Solenoid failed electrically, you usually get a code. There may be a vacuum leak related to this EGR code.
If you have a vacuum leak, it may be related to the 171 code.
Yes the o2 on the passenger side. The shift deal portion is most likely because I did have the cable break on me in Wyoming when things were stupid cold. The vacuum leak is possible. 200k on a Michigan truck, sounds like something may wear. The evp sensor, can I trace to it from the vacuum line? And does anyone have a clue for that 2 wire plug?
Pull the vacuum line off the fuel pressure regulator when the engine is running, if there is any fuel present the regulator is broken and needs to be replaced. While you're at that check fuel pressure, it should be 39-45psi with vacuum removed from the regulator and 32-35psi with vacuum attached.
So you have a connector near the front drivers side of the engine that is broken and disconnected is that right? A picture would help but a possibility is the intake air temp sensor which is located in one of the center intake runners on that side, and it's a round connector. If that was disconnected you should get a code for it so I doubt that is it, and that is the logic in my other suggestions.. the motor is running way rich with no obvious codes so fuel leaking into the motor from the FPR or really high fuel pressure are possible candidates.
the regulator is new as of 4/22. the picture im able to get is not really that great because the plug is melted.
not sure if that helps much but you can see where my issue is now. and i have to get a bulb for pulling codes. the mil light is inop right now. so i have to do that next for the new codes (if any) since last read. truck still has alot of work left to go, but after regulator,o2 sensor, and replacing the egr valve the fuel smell is not as strong but you can smell a good bit of richness (if thats a word lol) on order right now is a new set of plugs. my goal is to get it back to what it was before all financial issues when i was getting 18+ almost 20 on the highway. financial issues make less repairs done on the truck sadly.
another question is what are stock injector pounds? i want to say 19? looking to maybe do those. if i can find a set that someone may have not needed on here...anyone have a set laying around? lol
That could be...i didn't see a port there, that's not saying that before I got it things were changed. I wouldn't think that would throw a fault either. So that is pretty probable in my mind.
i replaced the line last fall. matched new with what i took off. may have been replaced prior. the colors are difficult to see, 25 years tends to do that. i know it all works alright though. i do agree it may be that PS sensor bacause it reaches right to the line.
my goal right now is getting as much of my mileage back out of her as i can.
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