Stalling At Idle Issues
97 eclipse manual 420A non-turbo motor stalls and stops at idle randomly, it always starts right back up. Sometimes won't start on 1st try then immediately starts on 2nd. Also jerks or bucks while driving but not all the time. If cruise is on it will jerk & cut off. Reminds me of an automatic trying to climb hill & can't decide to gear up or down rpms remain the same while this happens.
Troubleshooting Possibilities For This Problem:
First of all there are many possibilities that can cause this types of problem.But as per the problem described most of the common possibilities are ruled out.To confirm the problem for remaining possibility,its suggested to get vehicle engine control module scanned with scan tool.
You may end up having to monitor data on a scan tool at the time it acts up to be able to see what is happening.
It can be the Sensor Problem:
One thing I see you haven't replaced is the cam sensor. For your vehicle engine model the cam sensor mounts to the left end of the cylinder head and runs off the intake cam. If the cam sensor signal drops out it will cause the problems you are having, but it would usually set a code.
Crank sensor or Cam sensor Shorting:
One thing that isn't uncommon on these engines is an internally shorted cam or crank sensor taking out the opposite sensor. They both share an 8v reference circuit that they need to be able to produce a signal. If one sensor or the other internally shorts the sensor ground to the 8v reference then it will drag the reference down and prevent both the cam and crank sensors from producing a signal.
No Sensor Reference Signal To PCM:
No Error Code Set But Still A Faulty sensor:
A cam or crank sensor code will set if the PCM sees a signal from one sensor but not the other, it knows the engine is turning if it sees one sensor. If one of them shorts internally and takes down both signals then a code can't set even though one sensor is bad. If your cam sensor is shorting internally that explains the symptoms but lack of codes.
Possibilities To Try:
I recommend to get engine module scanned.But if no scan tool is available I would recommend replacing the cam sensor with a factory part (aftermarket sensors are known to cause many issues).
Jerking and Bucking while driving at High Speeds:
The same problem of faulty sensor or no signal for any of sensor is causing both the jerking and bucking while driving at higher speeds, but since the engine is turning faster at those times it doesn't die like it does at idle or low speed.
Also It can be Faulty PCM:
It's possible that the powertrain control module (PCM) could be causing this or it could be a wiring issue but these possibilities are less likely than a cam sensor failure. Replacing the PCM would be a last resort if all else can be ruled out.
This details will help.