My 89 Ram 318 fuelie auto, acted up around Christmas, where it will not accelerate. It starts and idles fine, but if you try to rev it up will not accept throttle, bogs, sometimes back fires. I replaced the fuel filter, and it has half tank of fuel. I started it this morn after sitting since New Years and it started with out a hitch, but will not rev up. Is it a throttle body/electical or what. Spring is here and I need a truck, any Ideas?

First, start by checking for stored codes. Key on-off-on-off-on within 10 seconds. See if anything comes up. Next would be to reset any soft codes that are not stored by disconnecting the battery for 30 minutes. Next I would check to see if the injectors have a good spray pattern with a timing light. Start there and see what you can come up with. Despite everyone saying to go to a carb, I've found these aren't that hard to work on.

I know little to nothing about fuel injection. How would you reset codes?

proper sequence for checking codes is on off on off on off on without cranking starting, watch for the blinking series. To reset you simply dissconect the battery for about 30 seconds. A FSM is invaluable in this case..

I had the battery out last night to move another old truck of mine,86 carbed, put it back in 2hrs ago no change still acting the same.

Mine acted the same way before and it turned out to be a corroded cap and rotor, so check those first. Also sounds like it could be the map sensor. Turn the key on-off-on-off-on and watch the check engine light for the codes if there are any.

just resetting the codes isnt going to fix the troubles.

Message center is flashing 5 times. I can't tell if there is long or short flashes all look the same to me!

Be sure the fuel pressure is around 14.5. If its 8 or 10 or similar, that's your problem. very common.

You need to learn how to read the flashes..

Yeeah

Flashes are read as a blink of the check engine light in the message center, and always 2 numbers. No zero and none start higher than 6. It will have a short pause between blinks, then long pause between digits and codes. Long and short is relative, maybe 1/2 sec difference. You should have a code 12 since the battery has been out within the 50 last key ons, and it always ends with 55. Mine always has 37 which is not a big deal, has to do with the A/T.

I also had a wasted cap and rotor when I first bought it and it would barely run. Good place to start looking.

Thanks for the info. I'll recheck the codes this evening after work. The cap button and wires were replaced in October, but it could be bad. The out door garage work doesn't appeal to me this time of year.

make sure you did not cross 3-5 plug wires

it will run but not run very well.

Are you hearing any hissing from the exhaust when the engine is running? On my '90 Dakota, the catalytic converter "brick" inside the case cracked, and pieces went down inside the muffler and plugged the muffler. Does the converter or muffler rattle when you bang on it with a rubber mallet? I had very weak power until I mashed the throttle one day out of frustration, and BANG, blew a hole in the side of the muffler... then the power came back.

Exhaust is clear, new muffler installed last Oct and converter gutted by previous owner. going out to see if I can interpet the code flashes.

Well I tried reading the codes. First set 3 flashes: 12 or 21 ? second set: four flashes: 13 or 22 or 31? followed by two sets of 5. Sorry but I couldn't tell short from long flashes but I did notice the pause between codes. Took me 6 tries!LOL TIA

There are no long or short flashes, just long or short pauses.

12 - PCM Power loss within 50 last key ons. To be expected since the battery has been out

13 - MAP sensor problem - Controls most fueling, that would certainly be something to look at

22 - Coolant temp too high or low

31 - Problem with canister purge solenoid circuit

Based on your description I get 34
34 - Open/short in speed control vacuum or vent solenoid circuits

55 - End of codes

Almost everyone in the world has a cell phone with video camera. Maybe take a video?