Hello Scotty :-)
I very like your posts, videos but I have hoped that I will never need to help :-/.
I have a horrible problem with my car - Peugeot 206 cc, 2.0, year 2002, petrol, 100 kw.
Diag. gave me (from several mechanics) the DTC codes P0300, P0302, nothing more. In original Peugeot garage, they only upgrade my software in ECU and erase/reset the adaptive values in it ... Engine behaves a little bit better but it did not solve my problem, they found out nothing. :-(
After starting the cold engine (mostly after night, several hours of "relax") it starts ok, but after 30 seconds it usually begins to shake. Sometimes it gives me a notice "antipollution fault", then somethimes "catalytic converter fault", too. (Chceck engine blicking), lost performance, I feel the misfirng, vibrates. But, if I hold the accelerator directly after start the engine, and water reaches 70°C - shaking stops and engine goes ok ... But, during the acceleration (not at same place - during moving of car) I hear some twitching/clinking/maybe rattle from engine area. I can not find out what it is and I am already grinding, hopeless and frustrated. I very like this car, it is my first and dream car, but that problem gets me in desperation. In winter, I still waited to warm it up by pressing accelerator every morning. Please, help me if you had some similar problem - what had helped?
I tried: clearing of throttle, changing MAP sensor, changing air temperature sensor, idle sensor/valve, spark plugs(already 3 times), high-tension cables -ramp?(over the spark plugs), lambda sensors are ok(they told me in Peugeot), changing air filter, fuel filter (pressure of fuel is ok, too), changing gaskets on valves (it "ate" a lot of oil, after that, it is a little bit better), pressures in cylinders have same values, battery is ok, alternator is ok, "timing" changed, if you will answer me anything, I can add more information (if I will remember something more). What way should I try?
I already paid more money for repairs than the car's value is.
But, one more information - when I turn the key in position that is before starting (it is not started yet) and I push the accelerator and release it(throttle is closed) - EGR valve clinks/twitches. Is it normal? EGR valve is new. Nobody can gives me an answer. Could it cause the problem? In my opinion, it should be in one position if the throttle is closed, shouldn't it?
I read that problems p0300 could be caused by catalytic converter fault (but diag.never gave me a problem with mixture air-fuel or exhaust), camshaft sensor, computer ... I will try to change camshaft sensor tomorrow, but I don't believe it will help. I skip the causes that I already tested or repaired. Can it be caused by bad catalytic converter? Or computer (ECU)?
I already don't have more patience and money for it.
I look forward to hearing from you and I am sorry for my bad english, I am from Slovakia. :-(
Thank you beforehand for any answer and I am sorry for long post, too.