I recently dropped in a 5.9 v8 into my dakota that was originally a 3.9. It has edelbrock performer rpm heads, hughes intake and roller rockers as far as mods are concerned. It starts but runs terrible, lots of black smoke from exhaust and backfires from intake. Any ideas? Also when cranking it will suddenly stop then start cranking again as if it’s hitting something but i have no idea.

 

Running excessively rich. What year is your dak, what year is the motor, and what PCM are you using?

 

Its a 2001. I bought a pcm on ebay for the 2001 5.9 dak, and had the skim system disabled. Compression is 210 psi, spark and fuel pressure are good and i set the fuel sync to the best of my ability with a multimeter
the motor is out of a 2001 1500

 

Check the coolant temp sensor. Probably hiding behind the a/c compressor, right next to the thermostat housing. Make sure it is plugged in, and actually works..... Have a scanner that can read live data?

 

The motor was just swapped in, so it doesn’t have coolant in yet but I’ve only ran it very briefly because it runs so poor. Could this affect the reading and could the sensor actually make it run this bad? I have hp tuners software I checked the fuel trims and they looked good, I almost think its an issue with the rockers

 

if it is hitting a hard spot while cranking and popping or bacfiring i'm sure you know how but check your work everyone makes mitakes and those that say they don't you shouldn't take advice from but check your firing order on your wires it sounds like 1 may be crossed if not go to checking your rocker arm setting cause you will have to reset them and check again if you want to be right !! But go to the basics and check from the start and follow through and it will show itself !! It sounds like you needed to walk away and regroup ..

 

and yes putting the coolant in would be a good idea but that shouldn't have caused popping through the intake ..

 

I appreciate the help, but I’ve double checked the rockers and triple checked the firing order. Its running rich overall all the plugs were carbon fouled which tells me its not just one.

 

Check the fuel sync. How's the fuel pressure?

 

Fuel sync is set the best I could with a multimeter, should be close enough. Fuel pressure reads 49 at idle I believe
i can provide a video of it running at request