Ok, I've lost some definite throttle response with my 99L. I know i've posted this several times before but i need some help..One thing i've noticed that may be the problem is that my supercharger doesn't seem to be spooling up as fast as it should through gradual acceleration...The whining sounds like its kinda weak sometimes. WOT the boost needle jumps up to 8lbs like it should so i take it the supercharger is working fine..I don't know if the engine has lost power or the supercharger.. Can anyone tell me some of the many different things that can cause power loss on a factory L besides:

Unchanged spark plugs, I recentyl installed NGK TR5s]
Fuel filter was changed again 2000 miles ago..
Air filter...I installed and air raid cone filter which i just cleaned...
Full service Tune up through ford..They flushed my fuel and intake sytem and changed the fuel filter ... 6,000 miles ago.
Mileage is 50K miles but even then it shouldn't drop performance too much.
Also i've done the Intercooler Swap and truck idles very smooth..
Oil is changed ever 3K miles with Mobil1 5W-30 Synthetics..
Fuel used is either Chevron 93 oct or Amoco 93 every since i've own the truck...

I recently used a bottle of Slick 50 fuel injection cleaner which i'm not sure if it helped or hurt my truck..It wasn't running much better before...The truck still has power potential but just seems to need minor effort to rid it's slight hesitation..Feels like the pressure of the pedal isn't 100 % anymore.. Any ideas would help..Thanks!!!

 

have you had the intercooler replaced?

just a thought

 

Brain fart ???

99: Have the fuel pressure checked. 99 Ls have had a fuel pump line come loose in the tank and/or the pumps get weak.

The teflon coating on the s/c rotors may be slowing it down. Check and/or change the s/c oil--supposed to last for 100,000 miles, but...........???

The cats could be clogged/blocked up and the o2 sensors could be worn/dirty.

Let us know what the final solution turns out to be.

Dan

 

Thanks LightningRod...I remember you told me about the fuel pressure problem before..I'm gonna take it to the dealer and have it checked...I didn't kinda notice a hose dangling from the bottom of my truck like it was unplugged from something..I'll keep you posted on the results..Thanks again!!

 

The fuel line I'm talking about is inside the gas tank as are the pumps. You can't 'see' it.

Have you tried Gene Evans Ford? They are high-performance oriented and have won Ford's President award.

Dan

 

Thanks Lightningrod..I went by gene evans today as a matter of fact. They told me to bring it in first thing monday morning and they'd do a test run for me to detect the problem..Thanks man, you've been a plenty of help.. I'll let you know how it goes

 

did you try leaning forward during acceleration?

 

An interesting bit of trivia about Gene Evans Ford. They are definately a high performance oriented Ford dealership. It used to be the home of the very famous Doug Lewis who now runs Ford Performance Specialists( http://www.fordspecialists.com )

Doug Lewis was also a SHO expert and was one of the few techs who actually knew how to work on the SHO, which is a mechanics nightmare. Although he is a SHO expert, he does lots of performance work on all Ford's, and i'll probably be paying him a visit after I get my Lightning since I know the exhaust on it's too quiet and will need to go.

 

June: Thanks for the info--I did not know that. I bot my L from them but have yet to need any service/warranty work. There were some interesting vehicles being worked on when I picked up my deep-breathin' honey!

99: Let us know their 'attitude' about mods, racin', etc. and whether they fix it.

Dan

 

The supercharger doesn't "spool up" nor is it slowed down by teflon. It is direct driven by the belt and unless the belt slips whenever the engine is at XXXX RPM the supercharger will always be at XXXXX RPM. Is this done with a SOTP meter or do you actually have some timeslips to show a performance loss? If so, how much of a loss? When did it first show up? Mods?