On my way home from work I was on cruise control, going exactly 70 mph, when I noticed all the cars passing me. When I looked down I noticed I was now going 55 and decreasing quickly in speed and my cruise control was off.

I could not get the cruise control come back on at all, so I just hit the gas and continued on. At 60 mph, no problems. At 65 mph, no problems. However, once I hit 70 mph, my car started lurching and jerking and the speedometer stick started glitching up and down. Once this happened I immediately slowed it to 65 and it stopped and did not continue.

I went ahead and pulled over to the side, shut the car off, and waited about 30 seconds. I started the car back up and took off; the cruise control worked again. Got it to 60, nothing. Got it 65, nothing. Got it 70... nothing! I maintained about a minute at each speed interval.

The car in question is an 02 Chrysler Concorde.

Recent work done to it: timing belt, radiator, gas compressor switch, brakes, and rotors. <I don't even think this information is relevant, but whatever.>

Anyways, does anyone have any suggestions?

Thanks a lot in advance!

 

Did the MIL (Check Engine Light) come on ?
Access to a scan tool to check pending codes?
Couple of things may contribute to the issue.
Believe it or not could be the Cam Sensor. Have seen these symptoms before and turn out to be that sensor.

 

Yes, the check engine light is on. Checked it a few days ago and it was sounding off 2 small exhaust leaks.

How would I know of it is the cam sensor? Are those hard to replace?

 

Do the "key dance" to get the code Switch the key on/off/on/off/on then the odometer will display P0xxx that will be the code. Cam sensor is located at the front of the engine/ center / peeking out under the plenum.

http://300mclub.org/forums/viewtopic...lit=cam+sensor

 

Well, I'll be darned!

At first I thought you were messing with me about 'the key dance'... and it took me four tries to figure it out: going forward slow, going back slow, turning it actually on and off, and then real fast going forward (but not on) and then it worked!

Anyways, the codes that I got were P 0456, 0440, 0340, and 0161. Come to find out, the cam sensor is 0340.

I'll go to the parts store and get this replaced tonight.

I really appreciate the help!

 

Okay, so I want to learn to work on cars.

Could you please help me to understand what the cam shaft sensor is and what it is for?

Also, could you explain what it is that my car is doing whenever it starts 'lurching' and jerking down the road?

Thanks,
Josh

 

Todays electroniclly controlled engines calculate fuel based on many sensors. Short version: ( There are more)
Crank sensor tells the PCM (powertrain control module) engine is spinning
Cam sensor signals where the engine is (#1 TDC Compression)
MAP sensor (manifold air pressure) vacuum in intake to confirm TPS
TPS Throttle Position Sensor, how far down you push the pedal
IAT Intake Air Temp (changes as air flows ino the throttle body)
All inputs help the PCM Calculate fuel and spark
Loss or intermittent cam sensor PCM may "guess" some calculations resulting in your 'lurching' and jerking down the road"