Ok so here's the deal i bought a 98 Dakota 3.9l truck, when i bought it the guy was tired of trying to get it to run, when i bought it he had taken the dist out for whatever reason and so for two weeks i was on this forum chasing down bad splices in wiring harness changing sensors, putting dist back in, until finally i figured out that the pcm he had in it came out of a Jeep Grand Cherokee so i bought a pcm and had it programmed to my vin. Now my truck starts but barely, can only keep it running about a min or two with it popping and strong gas smell. I know the pcm controls timing and I've moved the cap a Lil each way but nothing seems to make it get any better. I was told i may be a tooth off on my timing but seeing as how these dist don't have gears on them i don't understand how i can be since I'm guessing the oil pump is what is driving the dist and as far as i know nothing has been messed with in that area. I was told you can get it close enough to drive to dealership so they can set the timing perfect but i can't even get it to idle. Any ideas?

 

The PCM does control the timing.
Turning the distributor controls the fuel sync. It's likely off and that's why you smell fuel. A dealer can set the fuel sync.
There are lots of reasons that it may be popping. Did you check for any codes?

 

Check engine light is on I'm assuming because something is off and engine doesn't run right but when i scan for codes it just keeps telling me there's no codes stored in pcm

 

Did you end up pulling the distributor or was it pointed in the right direction when cyl #1 was at tdc?

If yes to all that then get a timing light on it and see when it is actually firing

 

When i pulled it this morning i had been playing with the timing so i pulled dist out then put cyl1 on tdc (i know this for sure after spinning it over a few times) put dist back in and seated it in oil pump and rotor was pointing roughly in the direction of the pcm so i turned dist so that the tab on dist was directly lined up with rotor so when i put the cap on #1 cyl cap post was directly over top of rotor

 

Could a bad camshaft position sensor since it controls injector timing be the cause?

 

And i don't have access to timing light, haven't needed one since my fox body mustang 15 yrs ago lol

 

Ok big change so got to looking around the engine compartment wiggling stuff and low and behold the big vacuum line going to brake booster wasn't really connected to intake, put it on and truck runs wasaaay better even idles now but when i rev the engine it gets to about 3000 rpm and starts acting like it has a rev limiter in it.... Injector timing maybe?

 

pull the battery connection for a bit and reset the ECU. Then fire it up and see how it runs.

Then check all the vacuum line ends for any leaks and fix as needed.

When I installed the JY ECU to get mine running right off the bat it was a gutless turtle. Took 50ish miles for it to come around and ~150-200 miles to come alive.