Hey all, new to the website and love it!!! I have quite a problem and need some help. I have a 1998 f150 4x4 extend cab 4.6. I have custom exhaust, orginal had 4 cats cut two off and ran straight back from headers. 78,000 miles and seems to be loosing power by the month!!! I had a hypertech chip in, pulled out....didn't really help. Also it is an automatic. What is really grabbing my goat is that the girlfriend has a new jeep and can kick my butt. Any help would be appriciated!!!!

 

Welcome!

I'm far from being an expert but I would like to pass on my opinion. First off, I can't imagine that truck was ever a powerhouse. The 4.6 is a pretty strong motor but it's a small V8. In your truck it's pulling the added weight of the x-tra cab and the 4x4 system. Power to weight. If you had the same motor in a lighter truck, or had the 5.4 in yours, it would probably be different.

Did the power start dropping suddenly? You might need to scan for codes. You might have something wrong.

I think one of the first things I would do would be to reset the computer by disconnecting the battery for about ten minuets. If you notice a difference, you might just have too much clutter in the computer.

I'm being pretty vauge. There are many possibilities here. We could use a little more info too. What, when, where, how. Stick around though. It'll all come together here. I don't know if you'll be ahead of that Jeep (it all depends on what it is) but you can almost definitly get back some lost power.

Good luck!

 

Which Jeep are we talking about. The Wrangler with the 4.0L has some get up and go with that light body. Same for the Cherokee with the 4.0L.

 

Clean your MAF sensor and reset the computer.

 

THANKS FOR THE INPUT GUYS, I WILL RESET THE COMPUTER AND CLEAN THE MAF IN THE MORNING. THE JEEP IS A 2002 WRANGLER XTERA OR SOMETHING LIKE THAT. I KNOW IT IS THE 4.0 L INLINE WITH A MANUAL TRANS. I HAVE RACED HER BEFORE AND WON, SO THIS PROBLEM IS PRETTY NEW.

THANKS DENNIS

 

You mention the exhaust system, but you don't mention anything that would improve airflow into the engine. If you don't increase airflow in, you will lose low end torque by increasing exhaust flow out. At least that has been my personal experience.

I used to have a Wrangler with the 4.0L and 5 speed, good luck trying to beat that. 3000lbs and 180hp makes for a very quick Jeep.

Rob

 

Trade vehicles with your girlfriend. Problem Solved!

 

Did you check the usual stuff first? Air filter? Fuel filter?