89 aries weird intermittent starting problem

[rbvrt]

I drive My k car everyday, And take care of it too.

Since I did the fuel pump, I have noticed another driveability problem. Once the car is warmed up and im driving on the highway.
The on-throttle response is like normal but as soon as I back off the petal just a little, the car will start to buck and act like it is missing.
As soon as I apply the throttle....back to normal. It dosent do the bucking thing all the time but when it does...it can be violent. Another thing that has been noticed...I recently replaced the radiator. Since then it seems like the car has 4 forward gears. Before the radiator replacement the car would not get up to normal temp. The guage would go up a little but not to the range that it goes to now. Well, since then I noticed that the car will go through its first 3 gears and then shift into a 4th when going over 55mph. Arent these cars suppose to have a 3 speed transmission?

The bucking problem is the main issue any help solving that would be awesome
89 dodge aries k LE 2.5L

Thanks guys

[Jacks1986Lebaron]

It could be a number of things.

As always have you checked for codes?? Even "if" it does throw a code it is not always the culprit causing your problem, but sometimes it can steer you in the right direction.

Have you checked your TPS (throttle Position Sensor)??
It could be that, but you could have a lose or cracked vacuum line somewhere...

check for codes first, then proceed from there.....

[88AriesLEwagon]

Thinking about people trying to track down vacuum leaks,I'm left to wonder,who ever thinks of the BRAKE BOOSTER as a potential vacuum leak source? They have a big old rubber diaphram in them,and over time especially if the engine is spitting up oil,or backfiring,that rubber bladder eventually dries up,swells up,or tears.Now you have a giant vacuum leak.I'm urging everyone with a possible vacuum leak,to consider the booster.They dont last forever,and 25 years or more is well beyond their normal life expectancy.And you could even have a rust through in the canister itself at that age!

[rbvrt]

Well, had the car up on the lift today and changed the o2 sensor and Im glad to say that the bucking problem is totally gone.
I also changed the cap and rotor just because they were so cheap. The old o2 sensor was very black and old. Its so nice to drive the car again without the shimmey. The power on and power off problem is gone too.

[K-CAR_WAGON]

Glad to hear your car is running well again. In regard to the transmission - as far as I know if you have an automatic with a 2.5l motor you have a 3 speed. I suspect the car may have been downshifting once on the way up (maybe because of the irregular running) making it seem like 4 speeds.

[rbvrt]

Thanks for the reply

I thought that too at first,it ts really weird, I have even taken my friends in the car and would start from a dead stop and count the gears on the way up.
Everyone who gets a ride is a believer after they feel/hear the car shift. It seemed impossible at first but I obsessivly count the upshifts every time I drive the car. Maybe im just losing my mind,lol
anyways the car drives nice and smooth with no bucking when I let off the gas which is nice because it was getting really annoying.

Does anyone know where I can get the plastic cover to the map light. Thats the only part on the car that is broken. I have the bottom piece just not the top part that swivels

[Jacks1986Lebaron]

Glad to hear your car is running good!! 02 sensor huh??

That part you are looking for, might have to be a junkyard find. Do you have a "Pull-A-part" up there in NY?
If so you can go on line, go to "Pull-A-part" and check to see if they have any k-cars on their lot, if so, grab your screwdriver and head over, you have to remove the parts you want your self, but everything is generally "cheap".

it also may be under "Pick-A-part", different parts of the country call it something different!!

good Luck and let us know what you find!!

[K-CAR_WAGON]

Maybe the last jolt/noise is not an upshift but a jolt/nosie from a lock-up torque converter kicking in. I will look for the part number for the map light cover in my 89 book when I get a chance and see if I can find a new part online.

[K-CAR_WAGON]

My 1988 Parts book has a lens, dome and map, listed as 3591873. I think (but am not sure) it is the same as on your 89. This supplier has one in stock.
http://www.arizonaparts.com/

I don't know whether his is new or used.

I would also make sure it is the correct one you want before you buy it. There are several interior light lenses listed in the parts book. You could probably also get one for a lower price in a junkyard or off someone who is junking their K car and is parting things out. (Frequently listings occur on the K car website.) I think the same lens was used for several years.

[88AriesLEwagon]

You could probably find a whole visor in a junkyard.The passenger side never seemed to get the wear and tear the drivers side does.