7/30/17
I have a 2003 dodge neon SE automatic transmission 2.0L, 160K miles. About 5 weeks ago I was having starting and power issues so I replaced the battery and alternator myself. I used the generic brand from O'reilly auto parts. The starting and power problems have gone away but something new has come up.
Every so often when the car is on and in drive but idling at stop sign or traffic light, the engine revs itself and bumps the RPMs up. The car doesn't do it in park or neutral, just drive and I don't know about reverse. Sometimes it does it every 8 seconds or so, sometimes 15 seconds, sometimes not at all. The car idles around 600 RPMs and when it revs it jumps up to about 800. When the car is in neutral, it idles at 800.
There's a second issue that I think is related but I'm not sure, I'm not a car guy. Sometimes when my car shifts from 3rd to 4th gear around 45 MPH, 1500 RPMs, the car slightly jerks. Not a lot, like hiccups for 2 or 3 seconds. If I accelerate or brake, it stops. It doesn't do it at all if I put more gas after the shift or if it shifts from 3rd gear to 4th gear at higher MPH or RPM. it only does it at specific speeds and RPMs. And sometimes it doesn't do it at all.
I don't know if these two issues are related. They both started after I replaced my battery and alternator. There are no other warning indicators like lights or beeps or dings or whatever. And it's not consistent, sometimes it doesn't happen at all but when it does, its very specific times and criteria.
Any one have ideas to look at? It's not in the greatest shape and I really really don't want to just take it in to a shop and be like "there's something wrong with my car" because I'll have no way of knowing if what they "find" is the real cause or a problem at all. I'd like to figure out what it is and fix it myself and only take it in to a shop as a last resort. Thanks for any advice or suggestions to look at with my car.