Ok I cant really tell you when this must have happened b/c my truck doesn't see anything over 3500rpm on a daily basis. So today when I was on my way home from work I got on the throttle a bit and had planed on letting the truck run though the top of second gear so I could merge into the freeway traffic. At around 3500rpm my truck began to shutter and just seemed like it lost all power. The truck runs and idles perfectly with no problems. Under high boost over 3500 rpms it feels like I got nothing. The boost gauge is reading around 12~13lb of boost before I will let off. The shutter is very consistant and will duplicate its self no matter what gear I'm in. I just changed my fuel filter not even 10k miles ago but I'm leaving for NAPA to get another one right now just to see if thats it. The big thing I'm worried about is that its a plug or something of that nature. Any help and advise I can get will be greatly appreciated.

Jason

 

If you have changed the fuel filter I would lean twoards the plugs. However, I would clean the IAC Idle air control unit and thye MAF meter before changing plugs. Hope this helps,

Peace,

Suavy

 

thanks man...I'll look into those things this afternoon

 

Have you checked your fuel pressure? Soon after I bought my Lightning (used), the same thing happened to me. It went through all the gears fine as long as I stayed off the throttle. Press the throttle more than half way and it bogged down. I immediately took it to a local shop and they changed the fuel filter, but that didn't help. They checked the pressure and it was 25 psi. It's suppose to be around 44 psi. They told me that one of the fuel pumps probably took a dump and I began bracing myself for the beating. After they dropped the fuel tank, they found that one of the fuel lines had slipped off one of the fuel pumps. They took off all the factory crimps and replaced them with SS hose clamps. The guys in the shop have worked on tons of Ford trucks and Lightnings and they said that they have never seen that happen before. The bright side was that I didn't need a new fuel pump assembly.

Cesar

 

Actually that is very common ... The 2 cents they saved on the
slip type fittings on the twin pumps come back to bite a lot of
customers. If ya gotta drop the tank, might as well put Walbro's in !!!

 

lose fuel pump?

It seems like a fuel delvery problem

 

I had this same thing happen to me, a few weeks ago. I had just started the truck pulled out into traffic and got into the throttle and boost went up and then all of a sudden truck just felt like it cut off, let up off the throttle and then gently pushed the petal down and everything was fine after that, still haven't had any problems again. It has me stumped as to why this happened.

 

Thanks guys. i'll be changing the fuel filter in about 10 mins. if i still have problems, then i'm going to inspect the plugs and coil packs. If still no solution then its to the local shop to check the fuel pump.

 

iceman: how did it turn out?

 

Diddo,

 

mine did this when the plugs were shot

 

Well i've decided to take it a step futher and do as much as I can while the truck is out of comission. I replaced the fuel filter with no results. Thursday the truck is getting the super charger/intercooler pulled off and cleaned, plugs changed and inspected. Then I'm going to inspect the fule pump. Shock Therapy put up a good post about moving the bed of the truck back about 3 feet rather then droping the whole tank so I'm going to try that. I'll update more on thurs. It the only day I'll have off this week.

 

Happened to me ...but mine was SNAPPED!

TG for a warranty

 

Well I was checking for an old post of mine when I noticed I never posted the cause of my problem. The wierd thing was I wasn't getting any missfires or anything in the computer. It was the driverside back plug. Sorry for the fuzzy pics.