lowce805

Hey guys just need some info..
Just wrapped up my 1998 4.6 to 2002 5.4 swap, started right up and idles great (no tune)..

- Now is it normal for it mis, and studder when reving or trying to drive?
Is it just the Tune thats needed?
- Local performance shop is asking $750 for a tune, is this the correct price for the tune i need?

Im in Ventura County CA and looking for the tune i need...

Thanks Guys

Javi_F-150

$750 for just a tune itself, and not the tuner!!! I don't have much experience in tunes or tuners, but I know VMP does custom tunes for 60 bucks a pop.

otto457

I'm assuming you used the PCM from the 5.4 for the new motor? It should all mesh except for a few sensors, the misfire is related to something else if you swapped the electronics with it.

lowce805

Im using the stock 98 PCM (4.6)

Javi_F-150

That might be your problem.

otto457

Ok the old PCM is trying it's best but with the new comp ratio, PI heads, and COP ignition it's probably struggling to figure out what's going on. Unless they're putting it on the dyno and giving you lifetime tunes $750 is a little high. Any reputable tuner should be able to flash tune it. Some datalogging may be needed but that would be the extent of what they would need to get it done.

http://www.troyerperformance.com/cgi-bin/ppistore.pl
http://www.powerhungryperformance.com/
http://www.vmptuning.com/store/index.php?

lowce805

1998 F150 4.6 to 2002 5.4 swap
Kept the 98 PCM and Coil Packs
----
- Initial start up; idle was PERFECT only ran for 5 minutes when I ran out of fuel.
- Everything was connected except exhaust (straight header)
- After pumping 2 gallons of fuel and driving it down the block it slowly got rougher, then stalled.
- I bolted up the new catback with all 4 - O2 Sensors and it seem to be missing an not wanting to idle :
----
Here whats going on now:

00gstang

That sounds like a HUGE exhaust leak. I had a car make that sound once...I thought the motor was blown ....but it was the exhaust !

00gstang

Then again...you used a 4.6 PCM to control a 5.4L engine which uses totally different fuel patterns and timing controls. If you drove it like that without tuning the 4.6 PCM with a programmer ....you could have leaned out the engine, making it go boom. You better compression test that motor and make sure it is still OK....

re54drider

Well forgive me for stating the obvious but if it ran fine before you ran out of gas, maybe you have a fuel delivery problem. Is it possible you had some sediment in your tank that got sucked into the filter? How long has the truck sat without running? Is it possible you sucked some water/bad gas into the motor? Maybe if you change the fuel filter you will fix the problem.