Hi! I have a 1995 Dodge Dakota sport 4x4 auto with a swapped in 5.9 from a supposedly 2003 Ram 5.9. Originally a 5.2, with the stock 5.2 computer in it now.
My problem is as follows: Rough idle, and it feels like it's missing when I gently give it throttle in park, especially at 1500-2000rpm. If i mash the throttle, it'll backfire through the exhaust.
When I accelerate slowly at around 1500-2000rpm I can also feel it's missing. It's almost like it's skipping although a bit intermittently. When I cruise at highway speeds, it's all fine uphill, but when it's a small decline or a straight it's basically jumping. I guess I feel it more when the converter is locked up. There's no problem at heavier accelerations and WOT.

What I've done with it:
New plenum kit (aluminium and new gaskets)
New wires, plugs, rotor and dist cap.
New ignition coil.
New crankshaft positioning sensor.
New O2 sensor.

I will try to set the fuel sync, but without a OBD1 tool it's going to be hard, and the distributor connector is extremely hard to get to for some reason, so it's going to be hard to do it using the backprobing method.
Any ideas? Thanks.

 

Which intake did you use? The 95 will have two temp sensors (one for the gauge, one for the computer) and it will also have EGR. What you may wanna do, is get the PCM from a full-sized truck that has the 5.9 and auto trans. (95 or older though, 96 is OBDII)

 

It's got a late model intake. No egr, and fewer vacuum ports. I'm pretty sure I've got both sensors plugged though. One with 1 wire, and the other with 2 if I remember correctly? Both broke when I fixed the plenum so I replaced them. Regarding the temperature, my gauge suddenly out of nowhere just always displays max temp.

I've been thinking of getting a 5.9 pcm, but I'd like the Mopar performance one, even though I have looked everywhere and they seem impossible to find. A base 5.9 pcm is expensive as well.

Do you think it's worth trying to mess with the fuel sync? I don't have a scan tool for OBD1, and what I can find on eBay is horrendously expensive.

 

No EGR is gonna be a problem..... the newer manifold doesn't have a provision for the second 1 wire sensor..... you would have had to drill and tap it. (unless it is a 96-97 intake?) I don't think you will find the performance PCM..... they make hens teeth look downright common.

Can you still find the Snap-On MT2500 on Ebay? They are generally 3-400 bucks, but, will do what you need....

 

I'll try to get an MT2500.
I have one single wire coolant sensor down behind the alternator, and a 2 wire sensor on the intake manifold.
Could you elaborate on the EGR? It's still plugged in, and gets me a CEL light after continuous highway driving, but disappears after restarting the engine.
Edit: the one on the manifold is the iat offcourse, but there is a 2 wire connector behind the AC pump, close to the thermostat.

 

PCM uses EGR to reduce combustion temps, so it can run more timing, without spark knock. Since these engines don't have a knock sensor, to clue the PCM in that its running too much timing.... you run the danger of blowing up pistons. If you are accelerating kinda hard, and your engine sounds like someone rattling a can full of marbles, that's spark knock, and can destroy your engine right quick..... For you, you might wanna consider upgrading to an OBDII system, grab the wiring harness, and PCM out of a truck with a v-8 auto, and dump the OBDI stuff. It's an exercise, but, doable. Need the stuff from a 96-97 truck.

 

Finding a spare Dakota with obd2 will be hard. I live in Norway, and we didn't import lots of these, mostly Chevy's.
I run 95 Ron on it (standard), which I believes equals 91 US? Never had pinging or marbly sounds coming from the engine. I don't believe that's what's causing my issue though, as it wasn't that bad when I got the truck. Gonna check fuel pressure, and disconnect one fuel injector at a time next. Might be dirt in the tank as well, so I'd like to pull the pump out and maybe also fix the gauge (unless that's a dash issue).

 

Could likely also source the PCM/harness from a full sized truck.

 

Pulled the pump out, and cleaned it. Nothing wrong with it, except the gauge doesn't work. Disconnected each injector one at a time, didn't notice something wrong. I did found a thread about a similar issue, and a possible problem might be the oil pump drive gear bushing, that holds the distributor shaft in place. Gonna check that next.
https://dodgeforum.com/forum/1st-gen...ottle-rpm.html

 

I manually set the fuel sync. Lining up tdc and cyl nr1 mark on the distributor, then reset the PCM. The stutter is gone, for now. Idle is still low and I feel and see a slight shake.
The rotor in the distributor felt good. Basically no vertical play, but there is a bit of play if i turn it side to side. Barely horizontal play.