My 5.3L into a Jeep Wrangler

[Chuck21387]

Next question....

We got the starter circuit (from jeep) wired up and works great, cranks fine. We thought, "oh, we'll use the Jeep fuel pump feed too" (because i wasn't getting any juice from my F1 pin....but i think that's because my ECM still has VATS on it which i imagine won't turn the fuel pump on because it thinks it's stolen.......so

Can i delete all the tranny info and VATS from my ECM? (i have a friend whose a "performance" guy with a small private shop....he can do re-programs...but hasn't done a 5.3 yet...any tips?)

[kwkenuf]

Yes, since you are running a 700R4, you should reprogram the PCM to think there is a manual trans back there. You can also disable VATS while your in the PCM. BTW, even with VATS enabled the PCM will still energize the fuel pump relay. However VATS will shut down power to the injectors shortly after startup if not disabled. If your fuel pump does not get power when you first turn the key, you have a problem with wiring to or from your fuel pump relay, pump or ground, not VATS

[1BADC10]

No power no pump.

[Chuck21387]

<div class='quotetop'>QUOTE(kwkenuf &#064; Jan 9 2007, 07&#58;46 PM) [snapback]78963[/snapback]</div>

Yes, since you are running a 700R4, you should reprogram the PCM to think there is a manual trans back there. You can also disable VATS while your in the PCM. BTW, even with VATS enabled the PCM will still energize the fuel pump relay. However VATS will shut down power to the injectors shortly after startup if not disabled. If your fuel pump does not get power when you first turn the key, you have a problem with wiring to or from your fuel pump relay, pump or ground, not VATS
[/b]

Well, i plugged a heavy gauge wire into the F1 pin, and when the key&#39;s on, there is no juice at all to that pin....so you&#39;re saying that even WITH VATS enabled, it should still fire...maybe...

Just a recap, it&#39;s a 2000 5.3 (don&#39;t know if computer programs changed...)

Here&#39;s what we have

Jeep 12v ignition going to A9 pin of C1 connector
Jeep ground to fuse block ground A6&7 pins

Motor ground cable to body ground point...
Jeep starter circuit, not using any of the chevy starter stuff....

[kwkenuf]

Can&#39;t help you with the A9, C1, F1 stuff...... But yes, the engine will fire with VATS enabled, but it won&#39;t run for long.
Hot wire your fuel pump to make sure it is working. Ensure you have the injectors, ignition coils and pcm powered up. Temp connect your puel pump to known good power and ground then fire that sucker up.......
I am unsure how you are currently powering your fuel pump relay but you can use the pcm to trigger it once you finalize your wiring.

[Chuck21387]

<div class='quotetop'>QUOTE(kwkenuf &#064; Jan 11 2007, 12&#58;00 AM) [snapback]79221[/snapback]</div>

Can&#39;t help you with the A9, C1, F1 stuff...... But yes, the engine will fire with VATS enabled, but it won&#39;t run for long.
Hot wire your fuel pump to make sure it is working. Ensure you have the injectors, ignition coils and pcm powered up. Temp connect your puel pump to known good power and ground then fire that sucker up.......
I am unsure how you are currently powering your fuel pump relay but you can use the pcm to trigger it once you finalize your wiring.
[/b]

My fuel pump works....it doesn&#39;t shut off, and it blew out an old line...i&#39;m using my intank fuel pump, rated at 140psi...but i wired it through the old jeep fuel pump relay, grounding out the old ECM pin so it thought it was there....but doesn&#39;t the motor have a regulator that turns the pump on and off?

[kwkenuf]

<div class='quotetop'>QUOTE(Chuck21387 &#064; Jan 11 2007, 04&#58;45 AM) [snapback]79248[/snapback]</div>

My fuel pump works....it doesn&#39;t shut off, and it blew out an old line...i&#39;m using my intank fuel pump, rated at 140psi...but i wired it through the old jeep fuel pump relay, grounding out the old ECM pin so it thought it was there....but doesn&#39;t the motor have a regulator that turns the pump on and off? [/b]

The regulator does not turn the pump on and off, it mechanically regulates the pressure seen by the injectors and send the excess back through the return line. Do you still have the 5.3 fuel rail with regulator and return line in place or have you modified that system in some way? Anyway if you are getting pressure to the rail, verify that your injectors are not stuck by either cleaning them on the bench or tickling them individually with 12V until you can hear them click when you apply and remove voltage (remove injector connector, apply ground to one terminal, 12V to the other, remove one lead and repeat until it clicks). Did you verify you have correctly powered the ignition, injectors and computer through the engine harness? Any your crank position sensor is hooked up?

Verify these things are operational and your engine should fire...... Have you installed a scan plug (ALDL) yet? And have you done a quick scan after a start attempt to see if you get any mal codes? all this stuff may seem like a lot but basically it is just like the old days... ensure, fuel, air and spark are available and you should get it to fire.

[Chuck21387]

<div class='quotetop'>QUOTE(kwkenuf &#064; Jan 11 2007, 06&#58;56 PM) [snapback]79329[/snapback]</div>

The regulator does not turn the pump on and off, it mechanically regulates the pressure seen by the injectors and send the excess back through the return line. Do you still have the 5.3 fuel rail with regulator and return line in place or have you modified that system in some way? Anyway if you are getting pressure to the rail, verify that your injectors are not stuck by either cleaning them on the bench or tickling them individually with 12V until you can hear them click when you apply and remove voltage (remove injector connector, apply ground to one terminal, 12V to the other, remove one lead and repeat until it clicks). Did you verify you have correctly powered the ignition, injectors and computer through the engine harness? Any your crank position sensor is hooked up?

Verify these things are operational and your engine should fire...... Have you installed a scan plug (ALDL) yet? And have you done a quick scan after a start attempt to see if you get any mal codes? all this stuff may seem like a lot but basically it is just like the old days... ensure, fuel, air and spark are available and you should get it to fire.
[/b]

We&#39;ll check all that out...i&#39;m beginning to think i wired the fuel pump backwards...it is a DC pump....so that&#39;s possible...

and yes, i&#39;m using the stock fuel rails and regulator. I need to check the injectors...what&#39;s a Scan Plug? ALDL?

And i&#39;ve wired the under hood (5.3) fuse block for ignition power, do i have to splice into the computer harness itself to give it juice too?

And all sensors (including CPS) are still hooked up through the factory harness

[kwkenuf]

<div class='quotetop'>QUOTE(Chuck21387 &#064; Jan 12 2007, 12&#58;20 PM) [snapback]79447[/snapback]</div>

We&#39;ll check all that out...i&#39;m beginning to think i wired the fuel pump backwards...it is a DC pump....so that&#39;s possible...

and yes, i&#39;m using the stock fuel rails and regulator. I need to check the injectors...what&#39;s a Scan Plug? ALDL?

And i&#39;ve wired the under hood (5.3) fuse block for ignition power, do i have to splice into the computer harness itself to give it juice too?

And all sensors (including CPS) are still hooked up through the factory harness [/b]

ALDL is Assembly Line Diagnostic Link... The OBDII port you hook up to when scanning your computer for check engine codes. It&#39;s handiny to have hooked up when doing swaps of this nature...

If you have an under hood fuse block from the same application as your harness you should be good, but its always a good idea to break out the schematic and ensure those key circuits are powered. Disconnect your PCM and check voltage from fuse to engine harness pcm connector pin... Grounds are critically important also.... You mention that you have wired the underhood fuse block for ignition power,... how is the rest of the block powered? The PCM needs constant power also. It will start without it, but it&#39;s kinda like disconnecting your battery every time you turn the ignition off. If you wired in your fuse and relay block following factory schematics I&#39;m sure thats not the isssue however.... You did didn&#39;t you?

[Chuck21387]

<div class='quotetop'>QUOTE(kwkenuf &#064; Jan 12 2007, 07&#58;58 PM) [snapback]79471[/snapback]</div>

ALDL is Assembly Line Diagnostic Link... The OBDII port you hook up to when scanning your computer for check engine codes. It&#39;s handiny to have hooked up when doing swaps of this nature...

If you have an under hood fuse block from the same application as your harness you should be good, but its always a good idea to break out the schematic and ensure those key circuits are powered. Disconnect your PCM and check voltage from fuse to engine harness pcm connector pin... Grounds are critically important also.... You mention that you have wired the underhood fuse block for ignition power,... how is the rest of the block powered? The PCM needs constant power also. It will start without it, but it&#39;s kinda like disconnecting your battery every time you turn the ignition off. If you wired in your fuse and relay block following factory schematics I&#39;m sure thats not the isssue however.... You did didn&#39;t you?
[/b]

the factory 5.3L fuse block is powered by the main batter cable. Which i did hook up to the positive battery terminal...the Fuse block is only grounded through a couple pins though...we thought that with that much current (the battery cable) there should be a large ground cable somewhere too....but none that we could find...