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Sorry if im posting this on the wrong forum but my problem is..

The car will drive fine and then out of the blue it will start shaking (rocking)... I have noticed that while this is going on you cant get the car to go into cruise control. Also if i pull over and stop and turn the car off and back on it will run fine again. Then a few days later it's back to shaking/rocking.

when i say shaking/rocking i mean kinda like your driving and pump the brake and take your foot off the brake pump the brake again take your foot off...etc

Anyone have this happen or know whats causing it?

So you are saying the engine is cutting in and out, or loping very bad?

Could be a TPS problem or possibly MAP sensor, solely based on the fact the Speed Control would not set. A bad TPS signal will not let the PCM set the speed. I noticed that issue when my TPS gave me problems. Wiggle the wires at the TB on the side. That is where the TPS sensor is. The silver thing on the top is the IAC control. If it starts idling differently, then the connector may need replaced.

Also with the engine off, key on three times, leaving the key on the third time. You odometer should give you some codes, especially if the CEL comes on due to the "shaking". If there are no codes, it will display "Done".

Thanks i will check that out and see if thats the problem

I wont be able to check your suggestion out until tomorrow but i have a question.

can i use a throttle position sensor and wiring from a 2001 neon for a 2004 neon? Just wondering because the local pull a part has 4 of the 2001 neons on it's yard.

or maybe i should just buy new to be on the safe side.. idk

here is a ? does it do this when you have the defrost on my car will buck just like im tapping the brakes its the a/c compressor cycling on and off

wargod4200 wrote:here is a ? does it do this when you have the defrost on my car will buck just like im tapping the brakes its the a/c compressor cycling on and off

No i dont think i had any ac/heat/or defrost on.
it has done it 3 times on me. The first being about a month ago.
2nd time was about 2 day's ago and then again today. All 3 instances it cleared up after turning the car off and back on.
it will probably do it again in a few day's if i dont have it fixed by then.

Yes, the 2001 to 2005 TPS wiring is the same. You can also buy a new pigtail kit from the dealer. But if you have a multimeter, check the TPS sensor first before just re doing the connector. You can carefully push the probes in the back past the little rubber grommets to get a voltage reading. It is the center, and one outer. outer are: 5 volt constant, the other is to the PCM ground. You want the ground one.

Should be the OR/DB wire (signal-middle) and the BR/YL wire (ground via PCM) The VT/WT wire is the 5 volt supply.

You should get a smooth increase/decrease in voltage with the key on. If you disconnect the connector to probe it, do it with the key off, or you will get a CEL.

Have you checked for codes yet?

well i'll be damn.. i have a second code
P0344 Camshaft Position Sensor Circuit Intermittent

i did have only one for a small emissions leak and now im getting the 2nd one above. I have an ultragauge and thats the code it gives me.

would that cause my car to act the way that i described?

Yes my old car acted like that when cam position sensor was going out the check engine light would also come and go off and on etc.

When you do the sensor make sure you clean the plug up really good with paper towels they tend to get a oil buildup which can cause issues as well.

Basically you will need to replace the sensor, and o ring. Most come with a replacement o ring.

The o rings do tend to leak. You want the sealing area as clean as possible when installing it. If it still leaks a bit, remove it, and reclean with a solvent degreaser, and put some RTV silicone around the o ring groove, and push the o ring back in, than bolt the sensor on. Don't go overboard with the RTV tho.

Having codes definitely helps get things going in the right direction.

And whatever you do, don't start the engine with the CPS removed. It holds the cam in position.