03 Neon feels like a vibrator

[yellomalibu]

Ha! Got your attention.

My mom's 03 Neon has steadily gotten more of a vibration over the years - it now has 130,000 miles on it and I just drove it today for the first time in a few years and it's bad. It's rattling the dash at idle and various cruise rpms - there are only a few rpms where it's tolerable in the car. The gas pedal even vibrates so much it was tickling my foot through my shoe.

It's so rough that I was wondering if it was running on all 4 cylinders, but when you stand on the go pedal, there would be an obvious miss if 1 or more of the cylinders weren't firing, right? It didn't feel like it was missing.

She just had my brother change a couple motor mounts, but I don't think all of them were changed.

Is there another motor mount that needs to be changed? Do they all need to be changed at the same time to get a smooth ride back?
Or is it likely something else like clogged fuel injectors?

[Barry Donovan]

try engine cleaners?

funny, I was just mentioning what hydraulic lifters do for this problem mentioned.

oil pressure reading high?
alot of little things to look for, mostly dirty engine.

a T-belt getting old can do that..I donlt know neons though. belted chained, beyond me.

[yellomalibu]

It got a timing belt around 95K.

I put plugs and wires in it a couple years ago, thinking that may help, but it made no change to how smoothly it ran... and I think my brother just did that again... again, no change.

I guess it couldn't hurt to run a couple tanks of gas treated with Blaster fuel injection cleaner through it; see if that smooths it down any.

[Deaf Bob]

Dirty/plugged/bad injector?
Bad coil, if multiples..
Can you remove plug wires to see which show no change, or isn't that not recomended?

Will admit I know nothing about the newer cars.. Basics apply..

[TC]

Do a compression check, also check your motor mounts...........

[Deaf Bob]

Well... Results? Or is poor mommy driving it still shivering?

[yellomalibu]

I just used her car today to drive her to the hospital, 90 miles away. (nothing had been done to the car yet, as she had been sick and not driving it) Before making the trip, I filled the tank and poured the suggested 1/2 bottle of Blaster fuel injection cleaner in the tank.

I think it's a little smoother, but perhaps I just got used to it... I'll wait until a couple tanks have been run through it to try to gauge a difference.

Is it safe to pour the whole bottle in the tank? I wouldn't hesitate on a carbureted car with no sensors or catalytic converter... but... although the bottle says it's safe for sensors, I was afraid to try it at double strength.

I did notice on this trip that her torque converter seems to not like to stay locked up... rpm's move around more than they should at relatively steady speeds.

[Ron Ward]

Neons and PT Cruisers suffer from the same curse. Do as TC recommends and run a compression check. Those engines eat head gaskets like a fat kid at a bake sale.

You may also want to check the coil packs. They have a tendency to cause similar problems.


Is the check engine light on?



Ron

[JeffMcKC]

It sounds like your talking about a frequency vibration. If it tickles your foot thats a way faster than engine rpm vibration, a miss is way slower.

Does it changes as you power barake it? If it does put in reverse and power brake it, Do this all easy your not trying to do a butrnout, see if it quits. If it does then lossen the exhaust up and the motor mounts and lightly power brake it to rock it in the mounts and then lock it back down ( this is called neutralizing the mounts, its done on new cars all the time) If this does not work then have sone on get it to vibrate and step on the exhaust pipe it may be grounding out against something. if so neutralize it the same way by loosening and or bending the mounts..

You can figure out the RPM level of it by using the Briggs and stratton governer wire they use to tune with, put it on the dash and tune it to the vibration then transfer the RPM to whats turning that fast.

[yellomalibu]

No, the check engine light is not currently on. It has come on a couple times in the past couple years while my brother had it and it was a sensor he was able to change... tps or something.

The vibration feels like the engine is mounted directly to the frame. I ran into an old friend tonight, who is a dodge mechanic at a dealership, and he said with no hesitation that it's probably the motor mount that fits inside the frame rail; when it goes bad it transfers all the vibration directly to the rest of the car, and that those engines aren't known for being smooth... He also said it pays about 7 hours to do the job, so it's more than I want to mess with. Mom can pay to have that one changed.

The compression check, I can do. I can also pull one plug wire off at a time, but I'm pretty sure it's running on all 4 - it just transfers vibration directly to the chassis.