Chris_1

iTrader: (1)

You should also check your fuel pressure....check your fuel pressure....check your fuel pressure

Chris_1

iTrader: (1)

45 to 60 psi

plumber man

Well the temp. Switch got the gauge operating again. Thst is awesome didn't like driving around without it. Pulled codes but only got one for an open nuetral safety switch, which i did bypass. Also got a running code 42 heated oxygen sensor circuit indicates system rich. And a 44 thermactor air system inoperative. My first time ever pulling codes so I'm not positive the running test is accurate so i will do it again asap. Thank you for everyone's input. Will keep you posted.

plumber man

Codes were same, not much. Ran truck today and didn't think i was going to make it home. It kept stalling but it took much longer before it would go. I notice that it occasionally has a miss when idling. I replaced the high pressure fuel pump and about a year ago the injectors and fuel pressure regulator was changed. I also changed fuel filter. Not sure what else i should do.

memoniz

I'm not sure if the codes would cause your problem, but there is an ignition side to your truck. I would start running tests on that.

mark392001

Code 42 is your Oxygen sensor which is screwed into your exhaust before the catalytic converter. Easy $30 or so part to replace.


Code 44 is related to the AIR pump system on this trucks as part of emissions controls. Code 44 is likely the small vacuum lines going from each solenoid to the vacuum canister or check valve. You should also check the vacuum canister (commonly referred to as the coffee can as it looks just like that) as they rust and develop small holes which will cause a loss of vacuum to the system.

riseandrun

Not trying to hijack this thread but for the sake of some info here goes. My 89 5.0 died on me on the way back for being looked at at my mech shop! Took the truck in for suspension, and whinning issues. Died 3 times on the way home. No power, wouldn't rev up. Got it towed home. Have not had ANY problems since! Afraid to take it out on the road, but still 25 miles around town runs fine. Is there ANYTHING being at an angle can reset to cause such an issue? Maybe plumber man needs to lift the front end 3 feet off the ground. I know this sounds ridiculous but look at all the parts he's changed already!
HTH

Aktech

Why even drive the truck knowing it is not fixed yet. It o2 is working just fine. It is telling u your not running right. I bet u have a leak. That's why the thermactor air system is not working.

plumber man

Ran a fuel pressure test and test resulted in 53p.s.i. not running and about the same while running. Well within range. Any suggestions of what to try next? I am stumped on the issue of problem only occuring while truck is cold. Like a sensor needs to warm up or a valve or plunger type thing is sticking until it heats up. Again not a mechanic so stop laughing. Appreciate all the help so far.

mark392001

It's a vacuum leak likely from one of the solenoids that isn't always active, which is why the symptoms occur sporadically. I'd check all the vacuum lines, easy to do and replace.