I got a 94 idi with an after market banks turbo. I bought this months ago and havnt been able todo anything with it. I put in a new trans filter and flush out the trans and put new fluid in it (atf merc/dex). I have codes for the VSS and FIPL. Now here what my problem is

From a cold start and drive, slight stiff shift from 1st - 2nd , 3rd and 4th no issues

Between cold and operating temp,
Stiffer shift from 1st -2nd slips in and out of 3rd and 4th doing 45 mph

Operating temp,
Only have first gear unless i put it into 2nd

I sprayed the VSS with electric cleaner it worked better for a day. Also my Tach dosnt work now it falls and bounces all around only works when idleing and at about 650 rpm.

I have codes for 023, 014, 029 with KOER

With KOEO 4095 and 13 both say see service manual.

Would the FIPL and VSS cause these issues? Would a bigger trans coller solve the issue? I've never had such issues with a truck and if i need a trans or TC i dont have enough time and money because im going to school in sept. I would much rather keep the truck so can some please tell me if they are the issues and how to fix them.

 

Yes they will.

A bigger trans cooler won't fix the FIPL or VSS problems that are causing your issues.

You need to fix the FIPL, the VSS, and the tach sensor. If any of those three are not working correctly the trans won't shift correctly.