Fuel Trims, MAF, VCDS, Data-logging, CSE Mathematics + Reading GRAPHS!

[r8wut]

I understand the temptation to blame the new o2 sensors for causing the multiple misfires across Bank 1 - I immediately did.

But the o2 lambda sensors have heating elements in them to get them up to temp very quickly in order to get the car running from open-loop to closed-loop operation.
Driving the RS for around 20-30mins post installation (probably too long), if there was any fault / failure of the o2 lambda heating circuits or similar a "related-DTC" would have definitely been set / flagged in either ECU in that timeframe - something along the lines of:

Oxygen (Lambda) Sensor : Heating Circuit: Short to Ground
Oxygen (Lambda) Sensor Heating; Open Circuit
Oxygen (Lambda) Sensor : Signal too Low
Oxygen (Lambda) Sensor Heating Circuit Malfunction
Oxygen (Lambda) Sensor; Internal Resistance too High


Whilst I appreciate the up-stream / pre-cat Lambda sensors which are identical by the way - are used by the ECU to regulate the Fuel Supply, the down-stream / post-cat Lambda sensors are used to monitor the efficiency of the CATALYTIC convertor.. and yes as correctly pointed out, can be mapped out / blanked out by a Tuner.

But, drawing inspiration from my CSE-level in Mathematical statistical probability and taking into account the Issues I outlined above - I would hedge a bet the HPFP(s) are at fault (being 17yrs old vs brand new o2 lambda sensors)

I also heard HPFP's can fail quicker or soon after a Major Service, including a Carbon Clean - because of the increased Air-flow and for the subsequent requirement by the ECU's for the HPFP's to work harder..

I guess we'll find out soon enough.. after which, if all is well - then yes I'll be taking the RS for a remap..
update to follow

[r8wut]

oh I agree it's been a quite a journey with this car (bleeding the clutch comes immediately to mind ) - but I'm a tenacious-petrolhead-sob

(as long as there's a good supply of decent Weissbier to cope with my frequent mood swings)

[r8wut]

ok - so the HPFP parts have arrived:

[r8wut]

Parts Ordered:

2x OE Hitachi HPFPs
2x OE Cam Follower / Tappets
6x Hex Bolts
2x Seal plugs / bolts
2x Washer rings

The part numbers are listed in the diagram below, for your benefit:

[r8wut]

Currently, my work-stack is such that I won't get around to installing and testing the above for a little while..

But I'm fairly confident when I do, install of the above will address the Issues experienced:

-Multiple Misfires
-Hesitation / jerky whilst accelerating from stand-still
-Sometimes stalling when coming to idle
-Slight Fuel Smell in Engine Bay
-Slight Fuel Smell in Oil Filler Cap
-Sooty Exhaust

hopefully I'll catch a break over the festive hols.. - if I'm not too hammered