I am looking at another ram. It is a 99, 360 auto.

When you punch it in first gear, it doesnt seem like it wants to go anywhere, until you hit a certain RPM, then it moves good every time.

Doesn't do it in any other gears, O/D seems fine, shifts fine, tranny fluid smells ok.

It has a quite obvious vacuum leak, and is throwing a code 0720 (output speed sensor).

I am thinking that if this is NOT the vacuum leak, it is probably the speed sensor - would that be correct thinking? It's quite a steal, so unless its something absolutely huge (1000s of $$), its worth buying if I can cough up the money.

Your thoughts?

Edit: When cruising at a lower speed, not at WOT, you don't notice it much if at all.

 

The speedo was working and the abs and brake lites are not on? If it has an "obvious vacuum leak", then yes, of course it could be sluggish, but, a vac leak won't give that code. Plus the plenum of course.

 

I know the vac leak wouldnt cause that code. 0720 is the one for the speed sensor on the transmission, which like you said, from what Ive read, a lot of times has to do with the speedometer and sometimes ABS/brake lights.

I could be wrong, but I didnt notice the speedometer or ABS lights acting up. But the CEL came on for that code. and there is a definite vac leak, its extremely apparent.

I guess my question is: does the sluggishness sound like the sensor or the vac leak, or both?

 

The speed sensor on the tranny is about $8 so you can always swap it (takes less than 1 min.) and take it from there.

Vacuum leak will definitelly make it sluggish at start and unnoticable at higher speed.

 

i'm guessing the hesitation is vacuum leak and the speed sensor is a different and unrelated problem. you can quickly prove it by labeling, then disconnecting and capping off all the vac lines at the manifold. takes only about 2 minutes. caution - you may or may not have power brakes.

drive it hard for at least 15 minutes and get the trans nice and hot. see if it up and downshifts right.

if its not running right, assume the worst. don't get caught holding the bag on a $1500 transmission rebuild w/o figuring that into the price.

 

Make sure its going into first gear, maybe fuel pump on its way, could check pressure on that