Could a leaky fuel filler neck possible cause the purge valve code or maybe even a vac leak?

 

Well since the vapor recovery system is a closed design, with a calibrated vacuum applied vapor recovery & charcoal canister storage unit, it sure wouldn't appreciate a leak!!!!!

I've not viewed the blinking codes yet, so post All code Numbers you think you now have.

Not sure where the IAT sensor was located on your year model, but its usually mounted close to, or contained in with the MAF sensor on later models. In the photo to the left, it looks like your air filter is exposed & if so, its sucking in lots of hot under hood air, which won't do engine power making any good, especially if the IAT is disconnected, missing, or has been relocated away from the MAF sensor, as that will mess up the computers calculation about air density, that it uses to calculate the fuel injectors on duty cycle, which affects the engines air/fuel ratio.

SO, did your engine bog/plug fouling/idle problems come about After you made the intake air plumbing changes????

 

I just replaced that actually but fuel pressure is at 30lbs I'd that too low?

 

Could I plug the vac where the line from the purge valve goes just to eliminate it as the culprit? Or would that be a bad idea?

 

Ok the best that I can tell these are all the codes that are showing up currently. I replaced the canister purge valve and since the fuel pump relay is relatively cheap I may go ahead and replace that too since its probably the original.

59*
AXOD 4/3 circuit fault - Transmissions

Transmission 2/3 shift problem - Transmissions

565
Canister Purge 1 solenoid/circuit failure - Solenoids

566
transmission 3/4 shift solenoid/circuit - Transmissions

556
Fuel pump relay primary circuit fault - Power / Fuel Pump Circuits

629
Torque Converter Clutch circuit fault - Transmissions

 

You could plug the vapor recovery vacuum line for a short time for a test, but I wouldn't leave it plugged for any length of time, especially in hot weather, but the code is for an electrical problem in the circuit, not a vacuum problem. Maybe a wiring problem, or electrical connector, or maybe the new purge solenoid has a problem, you did test it before installation....right????!!!!

 

No, how do I test that exactly?

 

If you have a multimeter, check the old & new purge solenoids operating coils resistance/conductivity. If you have some jumper leads, battery charger, or other 12 volt source, hook it up & listen for its solenoid to click as power is applied & see if you can blow through its vacuum hose connections when its energized.

 

Ok so yesterday the truck ran fine (for no apparent reason) and today it won't even idle unless I unplug the MAF. When I unplug the MAF it idles/runs great and has tons of power but I have to assume its not a good idea to keep drivin it with the MAF unplugged.

 

Ok so it died and now it's the opposite. It's running strong with it plugged in and won't idle without it plugged in. What the hell is goin on with this thing?

 

Well this may be the root cause of the bog & rich air/fuel mixture/carbon fouled spark plugs, if the MAF sensor has electrical connection or wiring problems, as it clues the computer about true airflow into the engine, so if its input to the computer is intermittent, or corrupt from the sensors heated element being dirty from debris from the air filter, or if that air filter is an oiled cotton gauze type thats been over oiled, it could have fouled the MAF sensor & corrupted its PID to the computer. Do you now have a trouble code for the MAF sensor????

 

No code for the MAF and I've tried cleaning it. Also I was thinkin it could possibly be a bad cat?

 

Maybe I need a new pigtail for the MAF?

 

If you've been driving it for a while with a rich air/fuel ratio, the cat may have been damage & if so the vacuum gauge graphics link has a test scenario for that, but right now it seems you have an electrical feed problem with the MAF sensor, so concentrate on trying to find out whats going on with it, maybe loose electrical connector pins or sockets, corrosion on them, broken wire strands, ect, fix it, then move on to any other engine codes, then to the tranny codes.
We are supposed to work the lowest trouble code numbers first, then move up to the next highest number/s & put them right, then reset the computer so it knows when a repair has been made.

 

The MAF connector itself looks fine. How can I test it? Should I pick up a different harness from a junk yard?