hi

i have replaced the distributor, leeds, spark plugs, coil, air filter. engine runs alright when its cold but the revs fluctuate and dont stay constant. after about 10 mins of driving when engine is hot it starts to misfire intermittently at firsts untill it gets so bad that it wont start. after it cools off it will run again fine. i really need some help i am at a total lost end, and have invested alot of time and money into my polo and really want it to pay off.

 

anyone got any ideas im thinking it could be a faulty lamda sensor or the temp cage that runs into the ecu could be faulty and giving wrong readings. but i have unplugged it when running and seems to make no difference, weather that test is fool proof or not I'm not sure. when engine has run for a while.

Edited 10 December, 20214 yr by polomade

i would look at the blue temp sender and its wiring ...disconecting it wont fix the fault as it defaults to -40

 

can disconect the 02 sensor to see if it helps