7.3 NA running as if it had a bad spark plug wire or bad plug.

[Duke57]

Engine is running rough as if it had a bad spark plug wire or plug. All injectors are receiving fuel. there are times when the miss stops and engine runs smooth.
When I crank up engine, hot or cold, always cranks up in 1/2 second. Old engine though. I posted pictures of one of the rocker arms and its pivot plate, plenty worn.
This is my only truck and it is driven daily for close to 5 years. Am impressed by these engines. I don't want to go back to any other type really.


In the final analysis I will have to look for a used engine till I save up for a rebuilt one.

 

[Nero]

The injectors may be receiving fuel, but maybe you have a bad injector. Have you diagnosed that? Or are you just throwing the money bucket at this point?

 

[ih8minimumwage]

Cracking injector nuts while running will tell you which cylinder is 'missing'. Either that or checking exhaust temps with an IR temp gun or thermal imager.

 

[Duke57]

The injectors may be receiving fuel, but maybe you have a bad injector. Have you diagnosed that? Or are you just throwing the money bucket at this point?

Actually haven't spent a dime since this started a week ago. I have just change the oil and fuel filter. Plenty of oil pressure at the filter under the hood.

 

[Duke57]

Cracking injector nuts while running will tell you which cylinder is 'missing'. Either that or checking exhaust temps with an IR temp gun or thermal imager.

I have cracked the nuts, and lose a little rpm at each injector when cracked. Sometimes when accelerating through the gears with moderate pedal, the engine would thrust forward a bit as if the engine received a timing advance so I thought the advanced piston might be stuck. Not an expert on the injector pump. I am going out right now to check with a thermal gun and check the exhaust port temps as you have suggested.
I have noticed that the engine runs smoother when cold then misses more when warm. then for no reason, at times, the engine will rum absolutely smooth, then go back to missing. heading out to check temps now as the engine is cold. It always cranks up, always has except when an occasional air leak shows up, very fast. Faster than some power strokes I have driven.

 

[Jesus Freak]

That sounds like air intrusion, or maybe the IP.

Sometimes when accelerating through the gears with moderate pedal, the engine would thrust forward a bit as if the engine received a timing advance so I thought the advanced piston might be stuck.

 

[Duke57]

That sounds like air intrusion, or maybe the IP.

The IP is my guess and injectors also. I am going to start looking for a used IP, can't afford a new one. I anyone has a used IP that works decently and you want to sell, give me a ring. Thanks for the reply.

 

[Jesus Freak]

I've got a couple, I'm in Crestview, where are you at in Florida?

 

[gnathv]

I’d try a heavy dose of hot shot’s secret and see if it frees whatever is sticking.

 

[Duke57]

I've got a couple, I'm in Crestview, where are you at in Florida?

Palm Beach County.

 

[Duke57]

I’d try a heavy dose of hot shot’s secret and see if it frees whatever is sticking.

I'll give that a shot, Thanks.

Mike

 

[Cubey]

I'll give that a shot, Thanks.

Mike

Be sure to keep it off your skin, or wash it off quickly if you do get it on you. I got some on my forearm and it gave me a pretty nasty looking chemical burn. It was on a paper towel and I used it without thinking to wipe off some muck. It wasn't like acid or anything but it ended up very red and itchy.

 

[Duke57]

I've got a couple, I'm in Crestview, where are you at in Florida?

Crestview!!! That's very nice up there! I am still stuck down here in south florida. Came back from North Carolina 23 years ago, kind of wish I never came back. Wish I would have finished raising my kids up there. I guess people are the same no matter where you are but this south florida is for the birds man. I hate it so bad. I was going to work on my truck this afternoon but had to take apart my wifes dashboard and work on a fresh air actuator on her 2004 suburban. I like all cars and makes but chevy sure went cheap when they crammed all of those wires and actuators up under that cheap plastic. Crumbles in you hands. Got the issue fixed so she is happy.

 

[Duke57]

Be sure to keep it off your skin, or wash it off quickly if you do get it on you. I got some on my forearm and it gave me a pretty nasty looking chemical burn. It was on a paper towel and I used it without thinking to wipe off some muck. It wasn't like acid or anything but it ended up very red and itchy.

REALLY? Thanks for the skinny. My skin is so thin now from working out in the sun most of my life. I can just brush up against a shrub and start bleeding. But I stlll wash off grease with chemicals, mineral spirits, brakeclean, whatever is handy. GOJO is the best though.lol

 

[Duke57]

I sure like my truck though. It's nice and slow, don't have to hurry, carries everything. Ole flatbed dually. Simple, no electronics, no a/c, no radio, just gets me there and back.