Stutters when cold or warm

[CKyle494]

The problem I'm having with my '00 F-350 7.3 is that it seems to flutter and the check engine light will come on. Some times it happens just after staring and letting it warm for about 5 min and getting on the road. It also seems to happen when I am in traffic and giving it gas to change to passing gear and all of a sudden it stutters and looses power, if I put it in Neutral and let it idle for a couple of seconds it will gain power and the light goes off. Or it may do it again for a couple of 3 times in a row, but more recently on my trip to the North it seems that I can be driving down the road, after about 250 miles, and it will do it once and a while. Kind of like water in the fuel? I use Diesel Kleen every other tank and I don't pull anything. I just like the room and mileage I get with it. It has 189,000 and I have changed the CPS and ICP switch about a year ago. Has anyone got any ideas? Thanks for this website...........

 

[JRJ04]

when is the last time you have replaced your fuel filter? air filter? any gauges to see what your egt's are doing?

 

[CKyle494]

I don't have any gauges for my EGT's, I have a 4" Banks exhaust, and a Automind trans kit from Banks, been on for about 3 years. I last changed my fuel filter twice in the last 5000 miles just incase of different places I travel has different fuel types ,mix. I have a AFE Stage II intake with a pro guard 7 filter and it was cleaned about 2000 ago also. It doesn't die like the cps it just kind of misses, like in a gas powered car when a plug stops firing.

 

[Tail_Gunner]

I used to have the stutter, buck, or kick problem periodically. It usually seemed to happen in colder temps or changable weather, and sometimes a day or two after filling the tank. Sometimes it would kick hard enough to cause the SES light to come on. I found that draining the fuel filter bowl would fix it for a time.

About 2 to 3 years ago I put in a real no S**T fuel filter/ water separator upstream of the fuel pump.
View attachment 6840


Since I installed the filter water separator, it hasn't bucked or missed a single time.

 

[Wingdog]

You need to find out what your fuel pressure is at idle and what it is when this happens. Your mixing chamber fuel screens may be plugging up. If you don't tow anything you won't notice it as bad but when you go to pass the demand for extra fuel is too much for the pump to pull past the screens and then the fuel bowl starts to draw down. These trucks will almost run on no fuel pressure at all. Gauges help for diagnosing all kinds of issues, they don't just look pretty!

 

[CKyle494]

Wingdog I wish I had the guages on there, not only to be cool but to help understand other problems if they happen, where is the other screens located at and how hard are they to change? And it does happen more when I get ready to "get on it" and pass. Would installing an additional filter like what Tail Gunner done help?

 

[Tail_Gunner]

Wingdog I wish I had the guages on there, not only to be cool but to help understand other problems if they happen, where is the other screens located at and how hard are they to change? And it does happen more when I get ready to "get on it" and pass. Would installing an additional filter like what Tail Gunner done help?

I suspect Windog is thinking of the particle screens that are part of the fuel pickup assembly inside the fuel tank.

I had done the "Hutch mod" several years ago and had experienced the bucking/stutter problem after doing that mod.

Gauges are a good thing. I have a fuel pressure gauge in the cab on my 4 gauge A-pilar mount. I got the setup that reads the pressure from the plug fitting on the back of fuel filter housing. Then that goes through a pressure isolater and from there to the gauge in the cab. Knowing that your fuel pressure is good, especially when the engine in under a load is a good thing. My old fuel pump had good pressure at idle, but would fall off badly under a demand.

Due to the circumstances under which I would experience the problem, I suspected it had to be a water in fuel thing. Changeable weather & temps will cause condensation in fuel tanks, and it seemed like I usually had the problem soon after fueling up. Due to that hypothesis and observation is why I decided to do the fuel filter/water separator mod. And I can honestly say it hasn't done it since. Coincidence or cure?

 

[BIG JOE]

I suspect Windog is thinking of the particle screens that are part of the fuel pickup assembly inside the fuel tank.

I had done the "Hutch mod" several years ago and had experienced the bucking/stutter problem after doing that mod.

Gauges are a good thing. I have a fuel pressure gauge in the cab on my 4 gauge A-pilar mount. I got the setup that reads the pressure from the plug fitting on the back of fuel filter housing. Then that goes through a pressure isolater and from there to the gauge in the cab. Knowing that your fuel pressure is good, especially when the engine in under a load is a good thing. My old fuel pump had good pressure at idle, but would fall off badly under a demand.

Due to the circumstances under which I would experience the problem, I suspected it had to be a water in fuel thing. Changeable weather & temps will cause condensation in fuel tanks, and it seemed like I usually had the problem soon after fueling up. Due to that hypothesis and observation is why I decided to do the fuel filter/water separator mod. And I can honestly say it hasn't done it since. Coincidence or cure?

FWIW, I totally agree with TG here. My, In The Cab, fuel pressure gauge, installed the same as TGs, is an Invaluable tool in monitoring fuel system condition(s).

I would bet that the "Stuttering", or power loss is a result of.. Fuel Pressure variations at different demands, caused by:

1. Air getting into the fuel.

2. Low fuel pressure.

3. Fuel Pump getting weak.

One, or a combination of all three.

You might try this ? Hook up a Fuel Pressure gauge so you can monitor whats going on while you drive under varying conditions. (the isolator is a Must) Note the Fuel pressures. (stock pressure should be 55 ish, psi) Then:

1. Eliminate the QD fitting (a known source for air intrusion) on the inlet end of the fuel pump with a piece of Diesel Friendly fuel hose. Start it up, let it idle fore a few, See what the gauge sez and how the engine runs while driving.

2. Shim the Fuel pressure regulator to 70 PSI. (There's a DIY on how to do it) Start it, let it idle, see what the gauge sez and how the engine runs while you drive it.

If the stock fuel pressure is below 55, and/or drops a lot, under a load ? the fuel pump would be suspect.

Got a Gut feeling you have "Air In The Fuel" issues. 1 & 2 will most likely fix yer problems. For Cheap too.

Joe

 

[Wingdog]

Wingdog I wish I had the guages on there, not only to be cool but to help understand other problems if they happen, where is the other screens located at and how hard are they to change? And it does happen more when I get ready to "get on it" and pass. Would installing an additional filter like what Tail Gunner done help?

Other filters never hurt especially if it one like TG's, just an additional water fuel sepparator. They are the particle screens in your fuel tank and you need to drop the tank to get to them. But don't jump right in and do this. Check and make sure what your fuel pressure is under load and that the lines are clear on either side of the pump.

 

[CKyle494]

Thanks all, I will get a Set of guages and the fuel pressure guage as soon as I get away from Boston and back to Tennessee. Thank you for the help!!!!