Okay my O2 sensor was bad based on my test stolen from a previous steve post,and the ovp was a bit flaky, I replaced them. Took the car in to get adjusted for fuel mixture based on gas and lambda. It was in deed very rich. So she was adjusted to factory spec (av 50%). However, my lambda was very flaky according to my mechanic and would fluctuate at idle. But was giving a very good reading at 2500 rpm. I also still have a horrible hesitation on acceletration from stop and a hard start. He recommended a new eha or throttle switch and to check the temperature sensor. I am at a loss, pretty much everything has been replaced now, and since the hesitation last week started I seem no closer. The only way to get rid of the stumble is to over rich the mixture. I am going to use steves test for the EHA but does anyone know what I should do to test the throttle switch and temp sensor. Please help.
2005 320 CDI
2006.5 VW Jetta TDI
1991 560SEL (179000 Sold)
1972 280SEL 4.5 ('The Lead Sled' 320000 miles when sold.)
1972 220D (225000 when sold)