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[jtypecav]

TB - I'll give it another shot in a bit. Lead foot and all that!

As for the throttle body and the sender on the pedal - I'd thought this and that's why both had been temporarily swapped out and tested with known working to no avail.

Next step? 

[TheBoy]

If getting TPS codes, with ign on (engine off), carefully watch APS and TPS sensors over full range several times

[jtypecav]

Not getting any adverse actual TPS codes active or stored. Although I was told the two tracks should total approx 5v and they sometimes look more like 3v total.

As for the APP TPP readings, here is the last run dumped into word and tidied up somewhat (it's pretty typical value wise)

[jtypecav]

Sorry, didn't realise you meant stationary there. Is it any use?

[Andy H]

I think TB means that you need to slowly open & close the throttle, several times, while watching the data. If the data jumps or sticks that is not good. You want to see smooth progression in the numbers in response to smooth input by the throttle pedal.

[jtypecav]

OK I'll take a go at this. The calculated numbers don't stack up in this anyway!

[jtypecav]

I think TB means that you need to slowly open & close the throttle, several times, while watching the data. If the data jumps or sticks that is not good. You want to see smooth progression in the numbers in response to smooth input by the throttle pedal.

On second thoughts, a crazy late night "do I have to drive it again as it" kinda thought..

As both APP and TPP have been changed and the numbers were very close and the problem prevailed, does that put this problem at the door elsewhere?

[TheBoy]

I think TB means that you need to slowly open & close the throttle, several times, while watching the data. If the data jumps or sticks that is not good. You want to see smooth progression in the numbers in response to smooth input by the throttle pedal.

On second thoughts, a crazy late night "do I have to drive it again as it" kinda thought..

As both APP and TPP have been changed and the numbers were very close and the problem prevailed, does that put this problem at the door elsewhere?

NO!!!

This is why proper disgnostics must precede random part changine. Why is the TP Load going invalid?

As AndyH says, smooth idle to full throttle and gently back a few times (hence ign on, engine off, so as not to rev the tits off the thing).

When you have done that, just take it for a test drive with the MAF unplugged, to see if it misses.

[jtypecav]

OK, will do this on my lunchbreak! 

[jtypecav]

OK! 

The headline is that apart from the car thinking that it's inlet was -40c and running quite lumpy compared to normal. It revved through the range (second image / third graph) with no EML - even though invalid TPS readings continued. Starts to feel like you are zeroing in here!

Pic1: Multiple cycles of throttle APP / TPP Raw Data






Pic2: All combined: Calculated APP (blue) Calculated TPP (red) with TP Status (green) and RPM (purple) overlaid.


NB Green Line shows IDLE (10%) PARTIAL (40%) and INVALID (100%) TP Status on ECU

[jtypecav]

So does unplugging the MAF make the ECU calculate air flow based on throttle position and engine speed alone? So a lot more rough and ready? And the lack of discrepancy between the two no longer being present means that the limp mode wasn't being engaged? This is me naively assuming that the MAF reading is lower or higher or less responsive somehow than it should be.

On top to the above does the ecu lean on the MAF more heavily in general as a compass in it's actions so a faulty MAF makes the ECU accuse throttle FBW components?

[TheBoy]

So does unplugging the MAF make the ECU calculate air flow based on throttle position and engine speed alone? So a lot more rough and ready? And the lack of discrepancy between the two no longer being present means that the limp mode wasn't being engaged? This is me naively assuming that the MAF reading is lower or higher or less responsive somehow than it should be.

On top to the above does the ecu lean on the MAF more heavily in general as a compass in it's actions so a faulty MAF makes the ECU accuse throttle FBW components?

Its pointing towards a duff MAF IMHO.  Only I'm struggling to prove it.  Some readings at different revs, whilst stationary, may help, if we can compare to a known good one.  Or if a nearby 2.6 member could do a temp swap?

[jtypecav]

Hmmn. Is Vectra 2.6 the same? If so I have one on an old vectra I saved (knowing I wanted a 2.6 mig one day) that my brother wrecked! It's 45 mins away but worth the drive if so.. I'd even go now *almost*..

[TheBoy]

Hmmn. Is Vectra 2.6 the same? If so I have one on an old vectra I saved (knowing I wanted a 2.6 mig one day) that my brother wrecked! It's 45 mins away but worth the drive if so.. I'd even go now *almost*..

I'm afraid I don't know without firing up EPC

[TheBoy]

PN is same on 2.6 Vectra-B