Any experience with 380hp mpfi conversion kit?

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jammied

jammied

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OK I have made a few engine harnesses from ram trucks with obd2 ecm's and haven't had any problems. They start,run and shift as they should in older vehicles.

Now I also have 2 of the mopar performance p5153734ab ecm's for the 380hp crate engine mpfi conversion kit. But can't get them to run on the harnesses I made.

I must be missing something in the instruction sheet and wiring diagram sheet from mopar performance as they will fire the engine right up but then they die in a few seconds.

Anyone play with the 380hp crate mpfi kit before?

Thanks for any help this is driving me crazy
 
Never messed with it beyond my 99 Durango. Not an expert but for conversation sakes, if it fires and runs briefly that tells me the pump is priming and you’re getting ignition. It almost sounds like it’s not getting crank signal to the ecu so there’s just the initial prime shot of fuel with no fuel pump past that. Easy to verify fuel pressure. I know not much help. Just my thought. Maybe draw some attention to your post from others that do know.
 
jammied said:
OK I have made a few engine harnesses from ram trucks with obd2 ecm's and haven't had any problems. They start,run and shift as they should in older vehicles.

Now I also have 2 of the mopar performance p5153734ab ecm's for the 380hp crate engine mpfi conversion kit. But can't get them to run on the harnesses I made.

I must be missing something in the instruction sheet and wiring diagram sheet from mopar performance as they will fire the engine right up but then they die in a few seconds.

Anyone play with the 380hp crate mpfi kit before?

Thanks for any help this is driving me crazy
Click to expand...
I know it’s probably a stupid question but how is your fuel pump wired, to pdc or ignition? Does it sputter when it dies or just kills? Could try and rule out fuel by bypassing ecu? But the first commentator was probably right on with approach. Let us know what it is when you figure it out!
 
Ignition switch gap between run and start resetting the PCM?

I have some info on those PCM’s, might be set up for a year that is different from your harnesses. Will look it up.
 
Thanks that would be great
And thanks for all the suggestions

My test motor and harnesses I have just been wiring direct to a hot wire off of the battery and using yellow red wire to jump to the positive post to engage the starter. So bypassing all switches . All the factory stock ecm's will fire right up and stay running. But the crate motor ecm starts and then dies. The instructions from mopar state that the 02 sensor isn't needed. The instructions also state that the wiring Harness in the kit is pinned for delphi iac and tps. Maybe the crate motor ecm has the pins changed internally? I did try swapping pins 1 and 3 on the tps plug but it made no difference. I might send one of the crate motor ecm's off to be tested. He seems to think that they have security locked
 
Also I tried it on a 1997 ram 2500 harness and a 2001 ram 2500 harness . With the same results. Both were 5.9 harnesses and I swapped between 1997 sensors and 1997 sensors. For testing
 
So you have the 380 hp SMPI instructions? I have pages 19 and 20 with the wiring diagrams or pin out, but can't find anything else. Sticks in my head that the PCM is 2000 based (that's what I built my harness for) but I can't find documentation. Seems like there are differences but sounds like not enough to matter.

Do you have the OBD2 plug? I've heard if you can short the CCD lines together while the PCM has power that the truck will start if the VTSS is killing it. But never done it myself.
 
BTW, my understanding is that if the PCM has ever been in a rig with a BCM that has VTSS, the switch is thrown in the PCM to always look for a signal from the BCM that it is ok to run. This is from the FSM.

So if the PCM's are used and had been in a truck (or other) that had VTSS, then I think you are fighting with the security system and need to have it removed (if possible?).
 
I haven't wired the obd2 plug in yet. Both ecm's were bought from summit new back when they were clearancing them out on sale. I haven't used them just dug them out of storage and tried for the first time this weekend.

I do have the complete instruction manual for them. Well I might try building a harness as per the manual schematic/diagram. Maybe there is a pinout or hookup difference I'm not seeing?
The instructions state the ecm's are loosely based on a 1999 ram ecm

Crazy usually the performance ecm's are very forgiving . They do have a sticker on them that says they need the vehicle reprogrammed. The sheet that came with the ecm's had a tech number that I called back when I bought them and the rep on the phone assured me that I could ignore the sticker. So maybe the rep was wrong that was like 5 years ago. Think I will go ahead and send one off to get checked. Maybe Summit sold me some bum ecm's or falsely labeled ecm's?
 
jammied said:
I haven't wired the obd2 plug in yet. Both ecm's were bought from summit new back when they were clearancing them out on sale. I haven't used them just dug them out of storage and tried for the first time this weekend.

I do have the complete instruction manual for them. Well I might try building a harness as per the manual schematic/diagram. Maybe there is a pinout or hookup difference I'm not seeing?
The instructions state the ecm's are loosely based on a 1999 ram ecm

Crazy usually the performance ecm's are very forgiving . They do have a sticker on them that says they need the vehicle reprogrammed. The sheet that came with the ecm's had a tech number that I called back when I bought them and the rep on the phone assured me that I could ignore the sticker. So maybe the rep was wrong that was like 5 years ago. Think I will go ahead and send one off to get checked. Maybe Summit sold me some bum ecm's or falsely labeled ecm's?
Click to expand...

Still sounds like VTSS to me. I wouldn't be surprised if the PCM's were just reflashed used ones and they didn't take into account they might have the VTSS flag set. But just a guess.

Sorry I can't help. Good luck.

BTW, what's this going into? Why 2 of them? Can't say I didn't wonder if you would part with one if it was an extra. :lol:
 
Why 2 ? They were extremely cheap on clearance lol. But maybe this is why. I might try your trick out this weekend I bet it is the security.

One is going in my 67 Valiant 2 door and the other was going in my race truck its a 1995 dakota. But I have the mopar carburetored magnum cam that sat between the 300hp crate motor and the 380hp crate motor cams something like .490 lift and 210 duration so I will probably have a different ecm flashed for the dakota. That In between cam put the 95 dakota into 8.8 sec 1/8th miles at 4500' completely stock engine 318 other than hooker super comps and mopar pcm and big air filter. Pegleg auto with a lot of tire spin when it hit 2000 rpm. The guys at the track couldn't believe it
 
Unless I missed it, I did not see anything about trying to keep it running with the throttle open a little? Have you tried?
I thought security was disabled on those, but who knows.
The crate motors that would run on had much lower manifold vacuum than a stock Magnum. Just wondering if it will run above idle, with TPS pins back where they were.
 
I actually did try opening the throttle body up by hand but it didn't seem to matter. Maybe the map sensor reading is messing with it? When it starts it fires right up and sounds good then dies.
 
Did you change the IAC and TPS connectors to get this wired in the first time, or did it plug in to the factory parts? This PCM is intended to run with a four barrel throttle body.
Just thinking if anything else could be making it look like a security problem.
Do you have a scan tool of any kind that would show sensor data? I would connect data line wires and check data before sending it off for testing.
 
These were new I never had the factory kit wiring harness. Everything I can see from almost every JTEC controller and the crate engine controller the main wiring for all the sensors and injectors are the same pinouts. I tried 2 different homade harnesses from ram trucks one a 1997 and all correct sensors and injectors and a 2001 with the appropriate for the 2001 ram sensors and injectors.

The 4bbl throttle body for the kit Used Delphi iac and tps Everything else for sensors are of the shelf dodge truck parts.

The delphi iac uses the same plug as dodge trucks but the pinned different but are interchangeable if the connecter pins are swapped. The delphi tps uses a round plug and is different from dodge trucks but either tps can be used. Back in the dakota forum days the daks running 4bbl throttle bodies would just swap pins or connectors and use either delphi or chrysler tps. 4bbl throttle bodies have pins 1 and 3 backwards and have to be swapped.

I do have the 4bbl throttle body and M1 intake but haven't physically hooked the ecm up to it. The reason they use a 4bbl tb is to help with part throttle drive ability not as touchy as a bored 2bbl. The mopar 4bbl tb flows 1000cfm a good bored 2bbl tb will easily do that and then some.

I will play around with one of the ecm's this weekend. And try everyone's suggestions or ideas.

And I appreciate the input
 
Hmm after studying the the wiring diagram for the mpi kit and a few truck schematics. I think the and and the fuel pump relay are wired different. Maybe I'm just getting bug eyed
 
OK so I did some more testing and built a harness with a aftermarket $20 relay/fuse box (didn't have the original pdm).

The original 97,98,99 JTEC controllers I have work on both harnesses. The crate motor ecm would still start and then die. So I checked fuel pressure on the rail and it was turning the pump off. So I ran power to the pump direct to the battery. And it ran 1-2 minutes revving from idle to about 1200rpm then died. So I'm convinced that the security is active in the crate motor JTEC.

And as DionR advised .... the asd wire in my diagram is incorrect. So I will have to revise the diagram I have.

Hopefully the Summit crate motor ecm's just have security enabled and actually do have the 380hp crate motor programming
 
Few pics of the harness I built/building and is the one I test ran this morning. It was a complete 1998 ram 1500 4wd harness minus the pdm. Still have to add a transmission relay and do some cleanup

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