My two pennies. Put a new selector valve in it.

 

Have you replaced the fuel filter ?

Is your check engine light on ?

 

You see, the problem with that question is that "weak" is an adjective that will mean something different to every single person you ask. But, when I got my truck, it seemed weak to me. My 99 GMC pickup with the 5.3L engine puts my Powerstroke to shame unloaded, but when the weight is on, the torque of the Powerstroke comes out.

So... If by "weak" you mean "slow", yes, that's normal.

 

Mine is so weak it flung the fan off like a rag doll...

But seriously...HOW much fuel treatment are u using? Getting fuel from a high traffic station? Need to check that fuel pressure im thinking as well.that whole situation does not make sence.

 

Changed the fuel filter 2 or 3 times. The engine light has only came on a few seconds before it quits. Idles very badly then and fuel pedal has no effect. After turning switch off and back on engine light goes off until next time it quits. There are no codes. I thought the weak power was pretty normal for this engine. What can you expect for 215hp according to the valve cover? My last truck was a hoss. With this one you don't burn rubber, win any drag races and have at least a quarter of a mile before you pull out in front of anyone.

 

I get fuel from all over town. I use what the bottle says on the treatment. Get 4 tanks out of a bottle.

 

It might be worth checking fuel pressure. About what does a gauge cost. Think I'll try to prolong changing that fuel valve out. Wasn't real cheap. Think mine is the $150 one at one of the parts store.

 

I have no idea if this could be part of it but it's running a staight pipe. No restriction at all. Someone told me it needs the back pressure for the computer to work right. Know anything about that?

 

Sounds like a crank sensor to me ...

 

There's a valve on the turbo whose only job is to make backpressure. If the engine needed backpressure, it could easily get the perfect amount from that valve. But it doesn't, so it doesn't. It only closes when the engine needs to heat up. After that, it's wide open all of the time. Plenty of guys on here have straight pipes and deleted the exhaust backpressure valve with no ill effects.

 

Yea.i got open pipe all the way.no problems. How ever u are checking codes....can u see live data.im wondering by that last one if the pedal sensor is not giving pcm info intermittently.and icp/ipr readings when it messes up.
After u add the additive how long does it take to clear up?

 

A business where my truck first quit at had a code reader and they checked it. NOTHING showed up. Couldn't say if they did it live or not. Also rechecked at AutoZone a few days later, still nothing. It clears up almost instantly after adding treatment. As long as it takes for it to get from the tank.

 

Just being curious, what are you guys getting on fuel mileage? I get better than 17 mpg IF I'll keep my shiftpoints around 2000rpm. Hard to do sometimes when I don't have that quarter mile before pulling out in front of someone.

 

It is a crewcab dually, by the way, so I didn't think 17mpg was too shabby.

 

That is fairly good.