CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

2002 Dodge Neon EX/SXT Engine 'racing'

I drove my daughter’s Dodge Neon last night and found that when I’m on the highway, the RPM goes up slightly every few seconds. I had about 30 minutes of driving until I was home so I tried to figure out if my speed had anything to do with it. It doesn’t happen when I decelerate or am at an idle. When I’m on a flat stretch of highway and using the gas pedal, the RPMs will increase. I didn’t notice the feel of the engine changing, I heard the engine speeding up a bit.

What kind of problem is this? I’d like to have an idea of the cost of repair before I take it to a garage. The car has 109,000 miles on it. Thanks!

Automatic? Did it feel like it downshifted?

Like Remco Asked, is it automatic?? If its not down shifting, then your lock up torque converted (I would assume this car has one??) is unlocking at speed… OR your trans is beginning to slip. Neither of which is great news.

When was the trans last serviced?

It may be normal if you’re criusing at a speed that’s just at the cusp of the tranny changing gears. Of course I’m assuming it’s an automatic, since you failed to tell us. If it’s a manual, the clutch is slipping.

It’s also possible if it’s an automatic that it’s a tranny problem.

Someone needs to look at it to find out anything definitive.

Sorry about that! It’s an automatic. It does it at 65 mph and 55 mph.

I don’t feel any shift or change in gears. I can hear the rpm changing - not feel it so much.

If an increase doesn’t have any kind of effect on speed and you don’t feel it shift, it seems like the transmission may be slipping.
That could potentially be bad news. How has it been maintained? Fluid is at normal levels and normal color?

We bought it last September. When we get the oil changed, the place checks the trans fluid. So far they haven’t said it needs to be replaced. I can take it by and see. I sure hope that’s the problem. A new transmission would be out of our price range.

Does this car have a tach?? If so how many RPM are we talking about… If it does not have a tach, can you guess how many RPM it jumps?

It goes from around 2.5 rpm to 2.7 or so. The needle doesn’t move much. It increases for about a count of 2 and then goes back to normal for about 10 to 20 seconds. Then it does it again.

It also does it at around 2.0 rpm.

It sounds more and more like the torque converted locking and unlocking… Every car is different, but usually once a TQ locks up it stays locked up untill you hit the brake or slow down far enough where it needs to unlock.

At least that is what it sounds like to me, it maybe a bad sensor or a bad torque converter… A pan drop and fill may help, but it may not… If you have not done one in 30,000 miles or more I would do it any way though…

Thank you!