Ive searched on here and really havent found anything. I have a 99 ram quad cab 4X4 sport 5.9 automatic. Trans rebuilt and the engine has 212k on her. New plugs, wires, plenum gasket, rear brakes etc.
I bought the truck about a month ago after the owner said it needed a new PCM/ECU. I started the truck and drove it up onto the trailer. I had to MASH the gas to get it up a low pro trailer. It was like the brakes were on or something.
So after finding out they didnt change to back plugs and the plenum gasket/pan were bad I replaced them. Yep new plugs, new aluminum plate and gasket.
I also found the brakes on the rear were installed wrong so that is done (it was binding).

The deal is the truck runs great but when you put it in drive and hit the gas its like brakes are holding it back. Its almost like its starting out in 2nd gear its so slow to get going. I mean she cruises down the road fine but zero power from a stand still.

Hers the kicker though. You can put it in reverse and she goes like a bat outa hell. Yeah no lag with power at all.

I do have a couple codes one for the IAC high voltage, one for the fuel sending unti low voltage (this is why my gas gauge doesnt work?)

Any help would be great.

jeff
USMC

IAC will be replaced tomorrow 1/9/12

 

IS it starting out in second gear? Or third? When you do get it rolling, do you feel the shifts? CEL on? Any pending codes?

 

did you have the trans rebuilt? or did the previous owner have it rebuilt? if the previous owner had it rebuilt did they have paperwork or just say it was?

 

it seems like its starting out in 2nd but then it shifts normal .... just slow. After she gets up to speed the truck drives fine but you still cant hit the gas and go. I have 2 other Rams so I know when something isnt right, I just wish I could figure it out.
CEL is on. comes on for the gas gauge (low voltage), IAC (high voltage). There was another code...I think a 1763??

Its just odd that its so pokey in forward gears but reverse is all power no hesitation.

jeff
USMC

 

previous owner said it was rebuilt. I know they could has BS me on that. I pulled the dipstick out and trans fluid was fine. I also dropped the pan and changed the filter and fluid 2 days ago.
So far I have had the plenum fixed, new water pump, new thermostat, new plugs, new belt, new pcv valve, wires were new just 2 not on right. New rear shoes seeing they had one side on wrong and they binded up so the trucks rear wheels didnt want to turn freely.
We also fixed a vacuum leak.

I didnt notice that the cap (adjusting screw) was missing so Im thinking it was messed with. I know these TB's are controlled by the ECU so ?? It still doesnt explain why the truck goes like a raped ape in reverse but bogs down in forward gears.

 

maybe you should try removing the o2 sensor and try driving it around? you said you repaired plenum but you said nothing about the cat. maybe it runs as good as it does in reverse because of how it is geared. i know on my dads ford can do 55km/h in reverse and that is not even redlining it.

 

Also, did you route the wires per the TSB?

Intermittents are always fun..... may be a failing crank sensor too.

 

I also removed the pre-cat O2 sensor and it did nothing. I couldnt tell it was undone.....besides the noise from the exhaust coming through O2 hole.

I didnt route the wires i just noticed 2 were not right. the 2 fronts on the drivers side.

I never thought of the crank sensor. I had the feeling it was the cat at first then I wondered about the trans itself.

jeff
USMC

 

Crank sensor can make your truck do some weird and strange things.....

 

ill swap out the crank sensor and see what that does. Ill also check the wires to see of they are routed correctly. im up for anything. Its driving me nuts that I cant figure it out.

jeff
USMC