V8 Swap, No Start


Broosedamoose

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Fuel pressure is fine. It never actually starts. When you turn the key it fires up and dies immediately. After that it will just crank. I tried disconnecting the TPS but that didn't work. At this point we are convinced that regardless of whether or not the PATS is disabled the module has to be present. We've checked everything else!
 


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RonD

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Early PATS Type B, 1998-2001 Explorer, did use a separate PATS module and it was "married" to the PCM at the factory, replacing either required you to "remarry" the units
The PCM on its own still waits for the PATS module to give it the "OK to start" message

But I also don't think thats the problem or it wouldn't fire up when cranking the first time, PATS is only active at Key ON, not while cranking or while engine is running.


If you can keep it running by spraying fuel into it manually after initial start up then spark is still working
If it still dies then spark is being cut off, so Coil pack is losing power or PCM is bad, thats all there is to the spark system

If you CAN keep it running by adding fuel manually then fuel is being cut off, so fuel pump or PCM is not working
 

Broosedamoose

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We are 100% sure it's getting spark and 100% sure there are no pulses to the injectors so it 100% the PCM. Now, the original PCM was an EQE2 calibration but I needed EQE3 for the tune I was given so I bought another one. Regardless of which PCM we use we get the same scenario. So, I don't think the PCM is bad. The fuel pump runs each time the key is turned on and I think he said it's building about 46-48 PSI. I could be wrong on that though. The point is, it's building pressure so it's not the fuel pump. We are just going to pull the PATS from the Explorer and put it in. If it doesn't work at least we can eliminate it from the problem. I wish someone who has done this build before would chime in!
 

Ramcharger90

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So I had this issue yesterday and today. Turns out the IAC came slightly unplugged. This could be your issue, it would fire and die for me also. Then again I used a A9L computer.
 

RonD

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We are 100% sure it's getting spark and 100% sure there are no pulses to the injectors so it 100% the PCM. Now, the original PCM was an EQE2 calibration but I needed EQE3 for the tune I was given so I bought another one. Regardless of which PCM we use we get the same scenario. So, I don't think the PCM is bad. The fuel pump runs each time the key is turned on and I think he said it's building about 46-48 PSI. I could be wrong on that though. The point is, it's building pressure so it's not the fuel pump. We are just going to pull the PATS from the Explorer and put it in. If it doesn't work at least we can eliminate it from the problem. I wish someone who has done this build before would chime in!
Fuel pump wouldn't come on if it was a PATS issue

You have tested injectors with NOID light and no pulses after initial start up?
That is odd
 

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OP... it sounds like your tuner didn't turn off PATS correctly

Scroll to the bottom of this link and fill out the automated vehicle info sheet and submit it. Be sure to include your xcal serial number. I'll shoot you a file to test to verify its not a computer related issue.

 

Broosedamoose

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decipha, I filled out thew sheet as best I could and sent it in. I can send you a copy of the tune in the BE format if that helps.
 

Broosedamoose

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I know when I looked at the tune using BE there only one switch for PATS and it was disabled. The only options are Enabled or Disabled! We've got all the wiring pulled out of the Explorer and started wiring it into the Ranger. Once we get that far I'll use the original PCM that's married to the system and see what happens. Keeping my fingers crossed!
 

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so spraying ether keeps it running?
 

Broosedamoose

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So we got all the PATS stuff out and hooked up but it didn't change anything! Still won't start! This is getting real frustrating now. What the hell could be wrong? What else could be shutting off the injectors?
 

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Who wrote your tune. You might want to give James at tuningbyjames.com a call. He deals strictly with ford and pats issues. He is a good guy and will help you out.
 

Broosedamoose

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Who wrote your tune. You might want to give James at tuningbyjames.com a call. He deals strictly with ford and pats issues. He is a good guy and will help you out.
We are using the stock Explorer tune right now. I have another tune that someone gave me but it's for a different code and I have a different PCM for it.
 

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Throttle position sensor at WOT(above 4.5volts) turns off injectors while cranking, it's called "clear flooded engine" routine, all fuel injection computers have that

BUT..................once RPMs are above 400 computer would start injectors regardless of TPS voltage
So starting engine with gasoline manually should take that off the table
 

bobbywalter

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the injector harness is firing correctly via noid...is it reversed?


do you have another set of injectors to try?
 


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