I was getting 1646 and 1647 codes, O2 sensors, so I got a couple of O2 sensors and put them in and cleared codes.

Whilst I was checking under the bonnet, I was manually operating the accelerator, I found that if I accelerated slowly all was OK. If I tried to blip the throttle, the engine hesitated before picking up. If I continued with the throttle blipping I could hear what sounded like a backfire in the exhaust.
Also, on a couple of occasions, whilst blipping the throttle I have found that if I blip the throttle quickly, fully open, the engine will stall. I notice that the idle revs are about 500rpm, seems low to me ??

This produces no codes on my scanner ???????

Any ideas? Bill W

 

Clean the throttle bore and plate. Clean the maf sensor and make sure there are no air leaks from air box to the throttlebody. Remove any slack in the accelerator cable at the throttle body.

And for s. & grins, a can of SeaFoam through a tank of gas.

 

Be careful cleaning the air mass sensor, be sure to use air mass sensor cleaner only. Mine was acting dogged and I cleaned it, didn't do much but clean up the idle, replaced the AMS and she screams again. I'm not saying yours is the AMS, but if its original, it is a good possibility.


Oh, check your CATS also if you have them in England. Plugged catalytic converters will do exactly what you describe and foul sensors.