So we finaly got the JLP motor in and it runs great and smooth. It is tuned using an SCT excalibrator but here is the thing..

The truck idles fine and drives fine in terms of the motor but the tranny is shifting "VERY" hard. I will be on the gas at only 1/4 throttle and the truck will take a long time to shift in every gear and when it does shift it feels like I was rear ended by an 18 wheeler. First gear is the best gear out of all of them and will usually not shift too late but still way to high a rpm at just 1/4 throttle. The other gears however are very bad. Shifting at like 4000 rpm when I am not even on the gas and when it shifts it is very very very violent. Also when I am just cruising and not even accelerating and it shifts from 3rd to 4rth it is a huge jolt.

So I decided to upload the stock tune back onto my truck and after I did that I decided to try and start it and to my surprise it idles perfectly. So I took it around the block and the tranny was doing the same thing. This leads me to believe that the stock tune was never re-uploaded so I went through the procedure again and uploaded the stock program and started the truck and again it idled smoothly. I was under the impression that due to the new injectors it would hardly idle at all with the stock tune. I have since unplugged the battery to try and get it to the stock tune but I am not sure if unplugging the battery will return the tune to stock.

Even shifting from park to drive or drive to reverse etc you can feel a hard jolt.

I am 99% sure its a problem with the tune and emailed Sal at PSP for a fix and know he will solve my problem but I thought I would post here to see if anyone has any input.

Here is a list of mods just for info...

2002 Lightning
Mods:
JLP Built short block
Kenne Bell Supercharger
3" Upper pulley and 9" lower pulley for a total of about 18.5psi
Factory Tech valve body
Siemen Deka 60 lbs/hr injectors
Twin 255 L/hr pumps

 

Make sure your MAF connection is plugged in good, if it's disconnected it will make your truck act exactly as you have described.

 

MAF is connected good and tight.

Sal emailed me and informed me the tranny settings were left stock so he feels the tranny went into failure mode. I double checked the connections and also the OD button is not flashing so I am stumped.

 

Whats up J Keep your head up I'm sure Sal will work everything out...

 

I have a check engine light that came on so I will get a friend to read the cod eand hopefully it has something to do with my problem.

 

When you did the motor swap, did you pull the trans or leave it in the vehicle>??? -Mat-

 

TPS? Just a thought.

 

No the tranny stayed in the truck. We took the cab off so were able to leave the tranny alone. Thats why I was pretty sure it was a sensor or tune problem. As you will see in my next post it was a TPS problem.

 

Damn! Youre good Hooked up the OBD II code reader for the Service engine light and sure enough is was P0122 (Throttle/Pedal Position Sensor/Switch A circut Low Input).

I made a post asking if this can cause the increased line pressure and super hard shifts as well as sent an email to Sal at PSP and his answer was "yes" this will cause my tranny to do the stuff it was doing.

Here is the link to the thread.

https://www.f150online.com/forums/sh...hreadid=191697

So again, verry good diagnoses on oyur behalf!