1992 Dodge Dakota 5.2 Magnum help and suggestions!!!

Hey everyone I have a 1992 Dodge Dakota with a 5.2 Magnum and a od auto tranny. The tranny does not always shift into od and when its not in od it backfires out the exhaust when u let off the gas when your driving it. Only backfires when not in od and when u let off the gas when your driving. Now when it does go into od it runs fine no backfiring out the exhaust what so ever. Does any one know what could be causing it not to go into od- and the backfiring out the exhaust? I did put new plugs and wires and cap and rotor on it. Didn't help. Only other issue is its hard to start- just cranks longer than it should I think. Im thinking that could be the fuel pump? Im going to replace that here shortly cause my gas gauge doesn't work. Its stuck between empty and 1/4 tank never moves.Would like to get this backfiring and od issu fixed .......... The exhaust is in rough shape has a hole in it. Im thinking about having a true dual exhaust system put on it with a x pipe or h pipe and a new O2 sensor. I dont have to run a cat cause its 25 years old. What size should I run? And what would b a good pair of mufflers to run? Want it to sound good especially at wot. I heard I may loose backpressure not running a cat??? Also what would be some other good performance mods? I plan on going to a 180 thermostat and 3923 plugs and a Mopar Performance Computer and a different throttle body. Plan on just keeping the magnum manifolds for the exhaust no headers.Plan on doing mods as budget allows..... Any help or suggestions would be greatly appreciated.

You didn't say how many miles on it, anything else wrong with it? Any and all information is important when diagnosing a problem.

Just an FYI, those trucks have a fuel filter on the frame rail. If it's been plugged for awhile it will take out the pump.

Has around 103,000 miles on it. I will change that filter when I change the pump. Other than the backfiring out the exhaust when not in od that's the only problems. This morning drove 2 work and it was fine but it was shifting into od. I do have 2 get a exhaust for it. This one is shot. That's why I was wondering about going with a dual setup.

check for codes and check fuel pressure first and second. I would get it running properly before thinking about mods. The 92-93 dakota/ram had some unique things about them like the big bore exhaust manifolds and its been said the cam and torque convertor were tweaked those years as well.

Some common 5.2/5.9 magnum issues to check:
plenum plate
EGR
spark plug wire routing
wiring splice corrosion under fuse box on 92-95 dakotas

If your exhaust leak is before the oxygen sensor, gotta fix that first. I have a collection of dakota y pipes if you want one. Dual exhaust kinda tight in that chassis

I know u can check the codes with light in the dash by using the key. But can u also just use a scanner also?

I have duals on my 5.2. I went with 2.25", no X or H. Thrush turbo mufflers were cheap at summit, they are too quiet.

Before you do anything get a OBD 1 Scan Tool, so you can check and clear codes.

Agree scan is a good idea... Autozone will do it for free.

From memory, those transmissions will not shift into OD until the oil reaches a certain temp... that may be what you are seeing with the shifting.

Good luck!

Update had a new exhaust system put on so no leaks now. Sounds good. Showing no codes. But the backfire is still there. Can barely hear it when in overdrive but when not in od its very noticeable. Changed distributor cap and checked the routing on the wires etc... Thats all new plugs, wires etc... Appears to be running lean. Next payday im going to replace the fuel pump and filter. Gas gauge doesnt work so I believe its the float. Hopefully the fuel pump and filter will solve this backfiring issue. Im stumped with it.

Only does it when your letting off the gas at higher rpms

Did you replace the oxygen sensor? Check the oxygen sensor and wiring. I had a 92 Dakota that had a backfire. The backfire went away after I replaced the sensor. Never threw a code.

New oxygen sensor when I had the exhaust done. Didn't help. I'm thinking it's the fuel pump or filter or possibly a blown plenum gasket. Going 2 replace fuel pump and filter and maybe the map sensor. If that doesn't solve it will do the plenum next.

Here is a long shot: Bad fuel pressure regulator. Maybe try blocking off the vacuum line to the regulator and see if the back fire persists.

Been a long time ago, but IIRC, my 92 5.9 got the part throttle/coast miss. Was a worn distributor bushing. I attempted to remove it while in the truck with a easy-out(spiral) bolt extractor lol. Wouldn't budge(imagine that), what ended up happening was that I inadvertently knurled the inside diameter of the bushing. That made the shaft tight, removed the slop, miss went away.
Good luck.
Troy

I went true duals on my '92 Magnum RC - I went Magnaflow glasspacks, and they snap crackle and pop like a MUTHA when coasting down a hill with 4.56 gears!

I also have the performance ECU for the OBD-1 Magnum engine, if the OP is interested. Gotta run premium fuel with it, though.