Hesitation. MAF? Lambda? Knock? Choke?
 

Ok...carrying this on from a previous thread...hoping someone knows whats going on haha.

Upshot is this, 2L UK Turbo 2000 MY99, factory standard. Car runs ok when idling, happilly ticks but revs perhaps a bit low as it judders ever so slightly, sitting around 700rpm normally, but ok.

When cold and running in 3rd or 4th gear at c.2600 - 4000rpm it hesitates slightly, runs 'lumpy'. When I floor it, past 4000rpm, it seems ok, but I know this is the closed loop thing, but now and then it will judder thru the rev range on acceleration.

Previously it was pulsing, and when I serviced it the plugs were black suggesting it was running rich, fuel consumption was also horrific and on occasion the car would smell like ma socks when I got out :lol1:. So...I've bought and fitted a new O2 sensor on the downpipe behind the turbo, the 02's from Camskill Performance and is a direct BluePrint replacement unit so no universal crap. Since fitting the fuel consumption is better and the pulsing seems to have gone also - but the hesitation/misfire remains, especially under 4k rpm.

Strange thing is when the car warms up a bit it does get better, doesn't go away, but not as interfering. So now I'm thinking MAF, but the signs all pointed to O2 sensor and I did have the MAF swapped at a dealership and went for a test drive for 5-10mins with the new MAF, the mechanic and he said the MAF had made no difference...so dunno if he just used a duff MAF lol.

Could it be the choke or the solenoid for the turbo sticking? The knock sensor which I've heard about or this MAF, and how do you actually know if it is the MAF without spending cash! Checked the ECU codes and only had 53, which is likely due to aftermarket ignition key I have.

Hope someone can make sense of this and steer me!!

Cheers guys in advance!

Jester

try throttle position sensor buddy thats wat it sounds like. unplug it then take it for a burn if the symtoms have gone u know its shot

tps mate pop it off and give it a clean