Chrysler Repair: 1994 Chrysler Lebaron GTC; rpm surges, lebaron gtc, chrysler lebaron

Question
i am experiencing rpm surging in overdrive between 30 and 45mph and was wondering what could be the problem?

Answer
Hi Benjamin,
If you mean the speed also increases proportionate to rpm, then that could be something like:
I suspect it might be an intermittent air leak at the intake manifold which is letting in air and then the feedback loop from the oxygen sensor noticing a too lean mixture is prompting the computer to compensate by lengthening the fuel pulses at the injector(s). That would be just like opening the throttle slightly were that to be the case.  You could try applying very small/quick spritz' of starter fluid around the edge of the intake manifold while the engine is idling to see if you notice a point where the idle speeds up momentarily which would be a suspected leak site. But use only extremely short bursts of fluid as this stuff is very flammable.
On the other hand, if the rpm surges, but not the speed of the vehicle, that would be the transmission slipping in whatever gear you are in at the moment. You didn't mention the engine type/size so I can't know which transmission type you have in the car (either a 3-speed non- electronic automatic with the 4 cyl engine, or an electronic type trans with the V-6).
If you have the V-6 automatic, then you would want to do a fault code readout via the blue socket next to the underdash fuse box to get any two-digit numbers stored in the trans controller. The readout is done via an OBD-I code reader and a Chrysler datalink connecter. So ask to be sure a shop that you ask to do the readout has the reader and the blue adapter plug. When you get the codes let me know what they are. This socket is NOT the one in the engine compartment for finding out engine fault codes, so don't make that mistake and get the wrong codes for that reason.
If the engine is the issue, then you could use the ignition key to do a fault code readout to see if the engine controller has identified a fault and stored a similar two-digit code. Turn the key "on-off-on-off-on and leave on" doing that in  5 seconds or less elapsed time. Then watch the check engine light to see it begin to flash-pause-flash, etc. Count the number of flashes before each pause. Then repeat to be sure of an accurate set of flash counts. Tell me the counts in order of appearance and we'll go from there.
Roland
PS Please rate my answer.