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Discussion Starter #1
I have a 1993 EXT 550 EFI Mt Cat. The 550 engine broke the crankshaft, so I bought a 1996 580 EFI with about 2,300+ miles on it.

Installed the motor with the EFI system made for that 580, throttle bodies & ECU...can't get the engine to run.

I turn the key on, and the fuel pump cycles. Getting fuel to the rail, but doesn't seem to get the fuel to the cylinders.
Pull to start, and there's spark to the both plugs.

The ECU flashes once when the key in turned on. I checked all the sensors with an ohm meter, all are within spec.
I checked the injectors for both resistance and grounded out the pins on the small ECU plug to get them to work, I get a strong 'click' with both injectors.

Any ideas? Is there enough diff. in the some of the components from my 1993 to the 1996 motor, that I need to change out some things?

Should I pull the injectors and see if they put out fuel?
 

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Yes I would pull the injectors and make sure they are not plugged. I have seen these get plugged and not let any fuel through. When you cycle the fuel pump are you sure you are getting fuel to the rail. You should pull the fuel supply line off the rail when you cycle the pump and make sure there is fuel flowing through the fuel line. Just make sure you catch the fuel in some type of container because it can come out pretty fast.

Hope this helps Jeff
 

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Discussion Starter #3
Yes, there is fuel to the rail, as I did as you suggested. I pulled the line from the rail, and turned the key on to cycle the pump and fuel came out.

I will check pressure today.

I forgot to mention that I had it running a few days ago, but only after I went thru everything with the ohm meter. It still wouldn't start, but it started and ran after I did the 'click' test on the injectors. I then proceeded to get the rest of the machine together and now it won't start.
 

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There are 2 relays on this sled one is for the fuel pump and one is for power. Make sure you are making good contact to the relays or you can run into problems also check all the contacts and make sure you coat them with dielectric grease to help with moisture.

Hope this helps Jeff
 

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Discussion Starter #5
I installed new spark plug boots, cut the wire back 1/4" and installed them and the spark is much brighter than before. For kicks, I tried starting it and started on the first pull.

It'll idle, but as soon as I try to give it any throttle, it wants to die. The head light is on and is bright.

I can feather up the throttle to the point where I got the clutch to engage, but that was a chore to get the engine to do that.

I reached down and pulled the throttle body cable only, and it wanted to die as well.

After a few minutes I shut it down, as it was smoking a lot. I cleared out the smoke and tried to start it again, no go.

Pulled the plugs, which are new...they are wet but not fouled...still very clean.

Before I read your last post, I picked up both the grease and some contact cleaner...I will go thru all the electrical to rule that out.

Are we getting anywhere?
 

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It also could be that the fuel pump is getting weak if the pump is not holding the correct pressure this can cause this problem as well. Let me know what you find after cleaning the connections.

Hope this helps Jeff
 

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Discussion Starter #7
I got ahold of some 'noid' lights, and checked the injector connections...and shows they are getting juice.
My battery was down to just a btad over 10 volts, so am charging it

Am going thru the connections now, cleaning and putting the grease on them. So far everything checks with the ohm meter.

Will be borrowing a fuel pressure gauge later, and will check pressure. Am thinking it is the pump, or some restriction in it.

I looked on the exploded view for my sled. and it doesn't show a filter. Not sure where that would be.
 

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Discussion Starter #8
2 things I noticed when idling;

1) If I just barely increase the throttle it'll rev up and as I keep going very slowly it'll go up to about 4-5,000 then drop off and want to die. When I let go of the throttle, it'll go back to idle.

2) Just for kicks, I changed the wiring on the injectors...in other words switched the connections. No noticeable difference...interesting.

All connections are cleaned and greased.

Could the stator be part of the problem?

If not...am thinking fuel pressure and/or TPS? How do you check if the TPS is working properly?
 

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Discussion Starter #10
Fuel is at 38+lbs and holds steady.

Stator checks at 476 & 49 = 525 when warm...is that too high?

I notice there's a difference in part numbers for the Regulator & CDI, from the 1993 EXT, to the 1996 EXT 580 motor I installed. Would this make any difference?

TPS, Injectors all check good...just wants to die at about 4,000 or so, and it takes pumping the throttle to get it to 4,000.

If I barely touch the throttle it wants to die.
 
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