I have a 95 150 5.0 and its spittin and sputtering I have changed the sparkplug wires, ignition coil rotor cap and egr valve I had it professionally timed and it is still sputtering I don't know what to do any help?

 

Have you ran a scan on it for codes? is this a mass air 5.0? does it have this condition all the time? just under a load? cold? warm?

 

You don't mention the spark plugs, did you replace them?

 

Ya it does this all the time and ya I changed the plugs and yes it says the o2 sensor but I changed it and it still doin it

 

Fuel filter?

 

Ya that was the very first thing I tried

 

Have you checked for stored codes? It can be done with a jumper wire and count the flashes or use a code reader?

Cutting out sounds like the stator is
or could be another problem. When you remove the distributor cap, is it crust down inside? The stator provides the PCM with the PIP signal.

Provided this is a '95, it has a black ICM and is a little different than the older trucks that use a grey ICM. If it were me, I would clean the inside of the dizzy really well and the connection for the distributor. There is also a 22k ohm resistor that lies inside the wiring harness that I have seen cause similar issues.

Start with simple diagnostics, codes, cleaning inside housing of distributor,and the connection for distributor.

One other thing, you never mentioned if this has done this for a long time, if this just started after running great, or if you purchased it like this. Just give us some background on the truck.

 

Speaking of basics.....check the fuel pressure at the fuel rail test fitting. Does the truck have two tanks? Does this happen on both?

Sputtering and an "O2 Code" (assuming it was a lean code) usually indicate lack of fuel or a severe vacuum leak.

 

Thanks RLA, I completely missed the O2 sensor change. If it was a lean code that could point specifically to a weak pump or fail in the fuel system.

Had same problem on my '92 300, weak fuel pump, and sputtering.

Rent a fuel psi tester or buy one. Post static and running fuel psi. Should be 30-35 static, running. Pulling vacuum line to FPR should cause it to increase to about 40.

 

Ya it has been doin it since I got the truck

 

Check the obvious things first..

Is the exhaust clogged?
Is the fuel filter clogged?
Is the air filter clogged?

If you can eliminate all those then check fuel pressure and pull the codes and go from there. The fuel system should build and maintain 32-35psi with the engine idling and pressure should increase to 40-42psi when throttle is cracked open momentarilly or vacuum removed from the regulator.

 

ya someone cut the cat out and I put a new filters in it but I put another o2 sensor it ran great for about a week or better and then started doin the same thing so I replaced it again and same thing runs great for about a week I don't know what to do

 

I had this problem with my f150 and it turned out that a bad/weak ground ended up frying my fuel pump. I could not go past a 1/4 throttle without bogging. check fuel pressure before starting, should be around 60psi if im not mistaken and when running should be about 55psi. Mine was fine at start but would go down to roughly 35psi when running which was barley enough to support truck at idle and it threw me all the same codes.

 

Definitely sounding like a fuel starvation to me.

 

Posts #8 and #11 told you exactly what to do. Quit throwing parts at it and guessing.