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1998 Plymouth Neon

I don’t know if anyone has ever experienced this before, or knows the solution but here it goes. I have a 1998 plymouth Neon sohc 4 speed automatic, as you drive it has a bit of a slow pick up and go, and it feels rough as it drives. All of the fluids are at their appropriate levels, and there are no codes showing up. Anyone have any ideas

How many miles on the car and when was the last time air filter/spark plugs/etc were done. It is an automatic?

it is an automatic, the air filter was replaced in may, along with the spark plugs and full tune up. it has 86549 miles on it.

Is the “rough” feel in the engine or the ride?

How long have you had the vehicle? Is it new to you?
Have you had any Check Engine Lights?

Are there any other operational problems?

If it’s the shifting that is rough did someone service the transmission and install the wrong fluid?

I have a 1998 plymouth Neon sohc 4 speed automatic, as you drive it has a bit of a slow pick up and go, and it feels rough as it drives.

Going by this description of symptoms, I’d have to say, it’s an almost 18 year old Neon automatic, situation sounds normal to me.

Well i had it refilled by dodge, and I made sure they used the correct fluid, it used to have a p1899 code, but that went away when I replaced the ecm. It feels rough when you drive as though it is dragging, or something is wrong with it, but no codes show up. The engine sounds rough also, but the oil is at normal level. I know that before I had the fluids flushed a week ago, the mechanic at dodge said the transmission appeared to be bone dry of fluid, as though it was drained but never replaced, and he refilled it to the proper level for me. I replaced the valve cover gasket myself, and it is not leaking any oil anymore. I guess you can say it feels like something is clogged or not connected accurately, or like the engine is not getting enough air or something and the mechanic checked everything, and just to make sure, I checked myself also, and nothing seems to be out of place or clogged.

On a flat surface, put the transmission in neutral at about 10 mph and see if it coasts freely.

It coasted freely for a little while, and after 15 seconds started to slow down a bit.

P1899 is a tranny code. Which control module did you replace?

When you say it feels like something is not connected correctly, do you mean that the engine is revving but the car not accelerating correspondingly? It sounds like it’s coasting properly, so I’d keep focusing on the power train and forget the rolling stock.

Frankly, it sounds like you have a serious internal tranny problem. Your best move is probably to get it diagnosed by a reputable independent tranny shop. I don’t care for chains, like AAMCO (the standing joke is that it stands for All Automatics Must Come Out), but you need to have a tranny shop take a look-see.

Did you adjust the transmission kick-down cable correctly when you replaced it? What RPM does the transmission up shift at full throttle?

OP said “transmission appeared to be bone dry of fluid”. That certainly indicates a serious tranny problem.

The transmission kick down cable was correctly replaced, the control module I replaced was the computer itself. I replaced the safety park/neutral switch and checked the wires after because the code p1899 would continuously turn on and the last resort was the computer itself, the PCM/ECM at least that was the only computer that would come up when I looked for it, and the one that failed when I needed to replace for the regulator when that code popped up.

ghviz : Sorry, I can’t parse your last sentence at all. Could you rewrite it?

I think he was pointing out that the powertrain control module and the engine control module were one unit and that’s what he changed.

I think he’s also saying that he checked the kickdown cable installation before changing the PCM and it was correct, and that he also changed the neutral safety switch, and that was when he defaulted to changing the PCM/ECM.

Sounds like he’s doing a good job, but now at a point where he’s wrestling with the need for major surgery on the tranny. Or possibly a boneyard tranny.

Ghviz, please correct me if I’m wrong.

You feel the kick down cable is correctly installed and adjusted, could you state the shift points?
Do you believe the performance is poor in all 3 gears?

An engine-bogging-down condition during rapid acceleration could be caused by lots of things, but what I’d think about first is a plugged engine air filter or plugged cat or valves not opening their full spec’d dimension. I think you mentioned that the air filter is of recent vintage. What about the cat? Has a intake manifold vacuum or exhaust back-pressure test been done? If the engine design has shim-adjustable valves, has the engine’s valve clearance ever been measured?

You are actually correct thesamemountainbike

The valve’s haven’t been checked for clearance, but I am at whit’s end with this vehicle, I am going to drive it till next november the way it is, and buying myself a Toyota Corolla.

Thought I would share this, but the problem seems to have been the oil refill cap, replaced it and the car is running way better then before.