the customer is always right. replacing 4.0 SOHC with 4.0 OHV

[now.what.ricky]

good day to you all. my name is Tom, i am a semi diesel mechanic by trade with very little in-depth automotive experience. i have found myself at a road block. customer brought me an 01 ranger with blown head gasket. long story short this trucks life has been rough and engine is toast. customer supplied me with a 99 donor with a 4.0 OHV and stated it should work for a replacement. i did some reading on it myself and felt that it could work. i swapped engine/trans/t-case/and pcm. i am currently stuck with a no crank condition. i have done some more reading and found the PATS system may be cause of no start. i am also seeing forums saying i need to use 01 engine harness and pcm. Ford dealer told me my only option is complete truck harness swap. dash/chassis etc. i do not have an automotive scan tool at this time but can borrow one to supply any information requested. need some guidance to get truck running. thank you in advance!

2001 vin:1FTZR15E91PA71780
1999 vin:1FTZR15X1XPB81233

 

[lowspeedpursuit]

Dealer's not gonna help. I'm surprised they would talk to you about something 25 years old at all.

I'm pre-PATS, but I think you either want to transplant the PATS system that goes with the '99 PCM, tune it out of the '99 PCM, or buy a non-PATS '98 PCM.

I don't think the cluster matters that far back. I don't think the '01 PCM will run the OHV properly.

From some light reading, if you manually ground the coil on the starter relay, and that switches you over from no-crank to crank-no-start, that should confirm a PATS problem.

 

[SenorNoob]

If I had both of those trucks here I would've probably tried swapping as many of the SOHC sensors and actuators as possible onto the OHV and dealt with the aftermath.

I know there was a case of a SOHC running on an early (93 maybe?) OHV control system. It didn't stay that way for long though. (I think it was in an Explorer.)

 

[now.what.ricky]

Dealer's not gonna help. I'm surprised they would talk to you about something 25 years old at all.

I'm pre-PATS, but I think you either want to transplant the PATS system that goes with the '99 PCM, tune it out of the '99 PCM, or buy a non-PATS '98 PCM.

I don't think the cluster matters that far back. I don't think the '01 PCM will run the OHV properly.

From some light reading, if you manually ground the coil on the starter relay, and that switches you over from no-crank to crank-no-start, that should confirm a PATS problem.

i will look into this. im gonna get my hands on some wiring diagrams for both trucks. thank you for the response.

 

[now.what.ricky]

If I had both of those trucks here I would've probably tried swapping as many of the SOHC sensors and actuators as possible onto the OHV and dealt with the aftermath.

I know there was a case of a SOHC running on an early (93 maybe?) OHV control system. It didn't stay that way for long though. (I think it was in an Explorer.)

this is one of the options i read about. hindsight is always 20/20! thank you for the reply.

 

[now.what.ricky]

UPDATE: customer only needs truck to run and drive, all other functions can be inop. truck is used on a farm. will a pats bypass module possibly resolve no crank issue with some potential hard wiring of certain functions?

 

[lowspeedpursuit]

Never heard of a "PATS bypass module". I was talking about a computer reflash. Quick search seems to turn up stuff that spoofs a key to an intact PATS system? If so, I don't think that would help with a PATS computer with the rest of the system missing.

 

[now.what.ricky]

Never heard of a "PATS bypass module". I was talking about a computer reflash. Quick search seems to turn up stuff that spoofs a key to an intact PATS system? If so, I don't think that would help with a PATS computer with the rest of the system missing.

gotcha, i did a quick search and am also not seeing an actual module. from previous forum reading i thought it was an option. might have to get an older pcm like you stated or send out current pcm to have pats programmed out like you stated.