92 Dakota backfires until it get"s to 40 mph. It then level's off and runs normal. If I get below 40 it starts all over again. I changed Cap; Rotor and coil. Same prob. Any ideas?

 

Sounds like something with the timing.

 

You may be right. One thing I noticed is that I can turn the balancer clockwise to the mark - line it up with TDC on the chain cover mark and the rotot sits dead on #1. if I rotate the motor counter clockwise the rotor sits haftway betreen #1 and #6. The firing order is 1-2-3-4-5-6

 

doublecheck your firing order. the order i found is 1-6-5-4-3-2. I also say it sounds like a timing type issue or a valve seating issue. A backfire condition quite literally is when during combustion, fire and stuff makes it way back up through the valve seat into the intake. This would happen if valve timing was off and the valve was not seating all the way, or if the valve/seat were in some fashion damaged/burned/etc.

You shouldn't turn the engine counter clockwise if you can avoid it. All the parts wear together in the direction the engine turns (clockwise) and turning it the opposite direction can cause issues. will it? meh, who knows, but it can, lol.

Hope some of this helps!

Cheers
Issakar

 

 

back in my day it was a timing issue. if it's the valves, chain or camshaft then it missed at 2 mph and 200 mph.
now it's computer controlled. i would look at one of the inputs to the distributor.

 

crazy4x4rt, where in the world did you find that 3.9 firing order? The correct order is 123456 clockwise. The 3.9 firing is the same as a 2.8 V6 GM motor123456. It was running fine on that firing order, then it began to back fire. I put a used coil on it and it ran fine for 3 or 4 days then started backfiring again. A new coil, cap, and rotor didn,t help. It has to be in the innition somewhere. I don't have a volt ohmn meter but plan on getting one the next time I go to town. I used the onboard computer but it shows there is no prob.

The diagram for the 5.2L is correct and is the same firing order for chevy V-8's.
When the problem started I called a friend who is a Crysler tekkie for more than 30 years and he confirmed that I had it wired correctly.

 

Thats the same firing order thats in the factory service manual, and btw thats the same problem i had with this truck, cept mine was throwing gas out the carb and never leveled out.. halfway thru the topend rebuild i was told id have to do, i found that the 4th and 6th plugs were mixed up and now im trying to get this engine back running. THANKS ISSAKAR AND CRAZYRT!! oh yea ima post up a few pics in another thread later to see if my seats are seated properly if anyone wants to confirm for me later... but yea big larry, i got the same info in the factory service manual and the same problem.... I feel your pain dude lol.

 

It is from the service manual, made by DODGE! If you don't believe it look at your intake manifold it is cast into it.

It may run with that other order but it is not what Dodge Engineered it to be at, that is why your having problems. Take it from DODGE who made the engine, and not from your friend who didn't.

If you still don't believe it call up your local Dodge Service department and ask.

 

All the Magnums are 92-02 all Stock intake has it cast into it.

It is not wrong the order is correct, it is the bottom set of numbers. Below the words FIRING ORDER. And off to the left side of the pic you can see the intake also indicates which cylinder is which. 4 and 2 are seen.

This is on my 5.9 Magnum. The 5.2 is the same. The V6 is in the same place.


The intake also shows the Distributer Rotation and Intake bolt Max torque.