H
y'all new to diesel bought a 93 f350 crew cab long box 4x4 7.3 idi e40d trans , was a dually conversion, anyways having trouble with the of light flashing and hard shifts, so I replaced the neutral safety switch , now it won't start in park, found the two bolts on the shifting linkage under the dash we're loose so I tightened them , no change. Will only start in neutral and shifts extremely hard

 

For the starting issue you need to properly align the MLPS:

courtesy of Steve83

The hard shifting is an indication the transmission controller is in limp mode so it applies full line pressure. Since you have a diesel I am not sure if the typical code reader, Innova 3145, can pull any codes.

 

Yup.It will.

 

Yes I made sure to disconnect the batteries, blocked the wheels , when I put the new switch on, dropped the front drive shaft to make sure I had the marks lined up, was in nuetral, also it come with a different style wire plug I pinned the same as the old one

 

Oh and I used a jumper wire and a test light, code 23 throttle position sensor , Wich I learned you need to have at full throttle while testing don't think it was the issue, and code 67 nss

 

If you are 100% certain the new MLPS is aligned properly then you need to verify the wiring is correct.



Since the truck will start in the Neutral position it does lead back to a misalignment issue or the new MLPS is bad. You can use the guide above to verify. Code 67 is another indication something is amiss with the MLPS.

 

Thanks for the confirmation the Innova will work. It looks like the paper clip method works too.

 

I will double check tonight, the picture above that style connection is what was originally on it with a tan colored mlps, the replacement I got from Napa was black colored with a oval shaped connection, is it possible that the one to replace it was a newer style with a different pin layout?

 

The pin-out is exactly the same for the old style versus new style connector:

 

Ok thanks for all the help, I will update later tonight after I get to work on it some more

 

Ok so two of the wires got mixed up white with pink stripe and the other white one Wich I assume is supposed to be black,shifts alot better now, thanks for all the help, one more question do you know what the specs are for the top there seems to be some mixed opinions on it my range is set closed at 1.05 and wide open is 3.78

 

Sounds like your talking about the FIPL/TPS now.The sensor up on the injection pump.Here you go:

 

Thanks for the link to the Ford TSB!

Looks like the Wide Open Throttle (WOT) value should be ~4.5 VDC. Very similar to a gas engine.

 

Yeah I don't think anyone has ever successfully gotten much over 4 volts,while maintaining their 1.2V idle though.I know I've adjusted for many hours over the years,either tinkering for fun and or while replacing and re-setting every 50k miles and I've never been able too.You get her reading 1.2V idle and take anything around 3.8+ and she'll run right on cue for ya though.Some guys with the lighter pickup's with regular beds,they like to dial down a touch under 1.2V idle though.With my heavy trucks,It's perfect.They claim a full 1.2V shifts too harsh.

 

Thanks i will try adjusting it tonight, it doesn't seem to slip but 1-2 2-D shifts are soft , and assuming when the torque converter locks up that seems nice and firm. Was worried for awhile that it might nred a new transmission, appreciate all the help 👍👍. Put 60 miles on last night shifts are nice just feel a bit soft no more harsh shifts though and OD light not flashing anymore think that was it 😁, speedo seems to run smoothly up until around 45 + mph the sensor on the rear diff was already changed so my understanding is the instrument cluster needs replaced to solve that correct? Sorry for all the questions just want to get it done right