Fellas,

I have been reading and researching trying to determine my best course of action. ALOT of good info here but may be too much for me. I could use some opinions.

HISTORY
My 2000 F150 XLT 5.4L is approaching 100,000 miles and was running really rich. i.e. I could smell unburnt fuel exiting the exhaust and only getting 12mpg city. Granted I dont have a soft foot and the 5.4 IS fun to drive. I bought the truck used, and it did have aftermarket graphics and racing tires on it when I bought it. The service history looked clean and it has been a joy to drive. VERY responsive truck, prolly the most responsive F150 I have owned. I was wondering if perhaps the PCM had been modded prior to my knowledge? Any way to know for sure?

RECENT HISTORY
In an effort to aid in fuel economy and sneak in a bit more preformance, I purchased and installed an AIRAID CAI and POWERAID throttle body spacer. I have seen neither a gain in fuel economy as POWERAID reports nor increase in tourqe or HP as AIRAID claims. In fact, the truck seems a bit more sluggish than before. If the truck was running rich, and the CAI did its job, is this why the preformance seemed to fall off as the mixture was leaned more toward factory settings? I read that since the MAF sensor isnt removed from the original housing the truck doesnt know there is a CAI installed. Why dont the people that make these d@mn things tell you that.

HELP
SO now what? I dont have another $400 to throw at the truck for a tuner and I assume the little box chips on ebay JucieBox and PowerMax et. all are really bogus as they just change the the voltage from the air intake sensors... what are my options and where should I go from here. Maybe one of you guys has an older tuner from your old truck you want to sell... Anyway any info would be helpful. Thanks and keep up the good work.

 

If you had searched here first you would have found that throttle body spacers are a waste of time and money. They make no difference other than some have reported a new whistle coming from it after it has been added.

After you added the CAI did you reset your computer? Did you clean your MAF?

If you need to clean the MAF do a search there is a good write up on here of how to do it and what to do it with.

I would take out the TBS and then reset the computer. Take off the negative battery cable and then turn the headlights on for 10 minutes. Shut the headlights off and hook up your negative terminal. Drive it around and let it begin to relearn its new parameters.

I don't have a tuner yet but from what I have read I want one and will be adding one soon. Do a seach, have a read and decide for yourself if it is something you want to invest in.

 

Throttle body spacers don't add any power and are a waste of money.

Just wait until you've got the money for the tuner and you'll be good to go !! I can promise you that you won't regret it. When you do have the money, go with custom tunes from a reputable tuner like VMP, PHP, or TP.

 

PCM tuning does not correct mechanical issues. With an almost 10 year old truck w/ 100K miles, I would just save my money and drive the truck. Wait until you've saved up enough for a new truck, then mod that instead. Save that "spend more money on performance mods into a used car than the car is worth" business for the Honda clowns. What next? Stickers?

 

Fifty - don't you think the truck still has some GOOD life left in it if it's worked on? I agree, a programmer won't fix it, but I'd sure start with a tuneup. From what I've seen here, a well maintained truck can get to 250K easily.

- Jack

 

Well, to get the most bang for his buck with performance mods, 100,000 miles is not a good baseline. I do not suggest adding power makers to a used vehicle with stressed parts. Let's just suppose that the engine and tranny are still strong, and will hold up to more horses & torque. How well will old brakes stop this faster truck?

5150

 

*hi-jack*

so the new- used truck i just bought has about 100k on it.... i shouldn't mod it performance wise? that kinda sucks.

 

And why not? The items you are adding are only going to make your vehicle more efficient. Not a high HP tire frying race truck.

However, first you should make sure everything is in A1 working order. Or you would be just throwing your money away. And tune and clean it up. Good luck.

 

100,000 miles on a truck really isn't that much any more. Some people can't afford or don't want a new vehicle so they should not mod there used ones? I have never heard that before. Most of the guys on this site buy used and mod them out with great success. It is pretty rare where I live to see brand new vehicles modded out as the owners are usually broke making their huge payments.

 

Thanks for the response guys. The fact is, the truck is paid for and with today's economy I dont want or need a $400 a month truck payment. I am a maintanence freak, and take very good care of my vehicles, trans flushes, brake and power steering flushed at proper intervals, not to mention oil and coolant. I got 178K out of my '97 4.2 V6 F150 and everyone told me that motor was junk. Actually it was the trans that finally made me sell that truck. I am not tryin to build a nitro burning power truck, just get more out of that 5.4L for the money. After reading more and more, I guess the 12.5mpg city I am getting isnt that far off the mark, I was just hoping for better.

Recently I have cleaned the MAF, TB, and looked at the plugs in the front right bank, they looked really good. Dont know about the COP's dont know how to check those. Any other suggestions on "tune up" you all were referring to?

 

COPs either work or they don't. You will know when one is not workin. I would leave them alone.