No Power While Driving

[rdr_1952]

1998 1500 Dodge Ram 4X4 5.9L Engine Was running fine and all of a sudden after shutting engine off and restarting it will not go over 25 MPH and on a high idle misses real bad....HELP I have had no problem before this problem started.

[dadof4s]

Originally Posted by rdr_1952

1998 1500 Dodge Ram 4X4 5.9L Engine Was running fine and all of a sudden after shutting engine off and restarting it will not go over 25 MPH and on a high idle misses real bad....HELP I have had no problem before this problem started.

How many miles on the truck? Might be cat convertor. Have you had it checked?

[BleedDodge]

That's what I was going to say! Just like always.

[Diablo_VT]

my dad has same type of 98 dodge truck and the tranny would every now n then hesitate between 1st n 2nd gears when starting to move after stopping. He took it to a transmission place and they wanted to do whole new rebuild and my dad said no cause he didn't want to spend around $3000 for a new transmission. But then we were driving around and low n be hold after they messed with it and did their diagnostics crap or whatever and told him that incase it breaks down that they'd provide "free towing to their shop" and what do u know...an hour later it acted like it lost all power and dad had to manually shift it from 1st, to 2nd then into drive to get it to go and then it still acted up and then when we were on highway goin about 55 in a 70mph it started to smoke really bad and guy pulled up and yelled over sayin he saw oil dripping out and that its smokin and my dad was like "yea, i think the transmission went to shit" and so the guy went on and we eventually made it to a shop and dad got estimate for rebuild and it was around $2000 and plus now its pretty much fried the transmission to shit so have no choice but get it replaced. however not getting it fixed at the shop he originally took it too, i still think they might of got mad that he didnt wanna pay them a bunch of money to rebuild it and they fucked something up in it to try n get us to get it towed back there to get it fixed...cuz yea thats kinda too coincidental that they say that and then an hour later sure enough it broke down. So... your tranny might be going out as well, or might just be the catalytic converter just not locking up to change gears like it should, either way i'd take it to a shop ASAP and get it at least diagnosed.

[tony36]

well, the cat converter doesn't lock up, it is part of the exhaust and can plug up and not let the engine breath properly. You must be thinking of the torque converter.

[Kevster324]

How do you test the cat? Will it throw a code when it is bad? I am having the power problem with my 99 1500 also (5.9l) I replaced the speed sensor, and did a tuneup (had multiple misfires when I scanned the ECM.) No improvement in performance. I am at my wit's end here. Any help?

[89ltd]

its strange with all that wrong it still doesn't throw a code. I would test the coil and throttle position sensor. Does it miss at only higher rpm or at idle as well?

[Kevster324]

Has a little lope at idle. Other than that, only misses at higher RPM. I can floor it and RPM's race and speed decreases. BIG loss of power.

[89ltd]

if the rpm's race than I would suspect the speed sensor, it is directly related to the trans and often will make it seem like the transmission is slipping. The computer needs a signal from the speed sensor for it to shift properly and in the right gear.

[89ltd]

if it were the convertor plugged the rpm will not go over about 1500.

[Kevster324]

Speed sensor was changed a week ago, with no improvement. I haven't checked the ignition coil yet. I will check it out also.

[scoutinkeith]

I'd assume that the 98's are the same? but the 99 that I used to have had two speed sensors. not sure which one you changed, but i'd imagine that you would want to change the one on the trans, as the one on the axle is basically just for low speeds, and the spedometer.

[Kevster324]

Mine is a '99 and I changed the one on the tranny.

[Kevster324]

OK, I replaced my ignition coil yesterday. Made no difference at all. Even when in park, if I rev the engine I can only get about 3000 RPM. I'm suspecting a plugged cat at this point. By the way, called Dodge about extended warranty or recall on my cat...no deal. Seeing as I have a 5.9, the warranty/recall does not cover. How difficult is it to replace a cat with a universal weld-in type? Direct-fits are waaay too high. Anyone know where to get an inexpensive cat?

[Austin8214]

I would check TPS out before you go buy a CAT. As for an inexspensive CAT any muffler shop should have one or I think they sell some at autozone as well.