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[chrisgixer]

At a roundabout. Trying to judge the traffic to pull out, hard on the throttle then off again after a momment of doubt, brake, then back hard on the throttle....

....nothing....  .....still nothi.... Ah finally away we go.

No engine revs, so not a slipping box, on gas but not quite fully warm. About 70c on the gauge.

So just to recap, happened at about the pace you would read it the text;

Full throttle Off throttle brake full throttle.... .....no response.... no response.... Gently power comes in/revs rise.

Did I confuse it or is there an issue? Iirc they can get fuddled momentarily.


Shit driving really i should of either just gone or waited. But didn't give on coming traffic a problem. Although if it had waited any longer.....

[zirk]

Haven't got any rubbish tyres fitted per chance, maybe they were spinning round and smoking like a good un, but seeing as your busy looking at the oncoming traffic you never saw the TC Light flashing.      

[chrisgixer]

Haven't got any rubbish tyres fitted per chance, maybe they were spinning round and smoking like a good un, but seeing as your busy looking at the oncoming traffic you never saw the TC Light flashing.      

Engine revs didn't respond.

[05omegav6]

Sounds like a momentary snafu... If you press the throttle with your foot on the brake on a diesel, the engine literally chokes itself... Wonder if this caused a similar effect, disrupting the plenum vacuum

[TheBoy]

Just the once? Or has it happened before?

As always with LPG cars, first step is to see if it does it on petrol - but if its a one off, that will be impossible.

I'm sure we've seen similar with 3.2s and LPG, where on-off-on throttle gives a lag (and it happens on petrol, but LPG amplifies the problem), though normally at higher RPM?

Lastly, are the trims roughly where they should be? Had it been idling for ages (enough to whack the LTFTs out of kilter, so when booted, it was hestitant).  Might be worth, on LPG, monitoring LTFTs over 30 mins of idling.

[chrisgixer]

No tick over. Jump in, start, drive off. Then probably two minutes of 30-40 limits, quick blast up to 70, then stop for the round about. Car in front pulls away, my turn, then the problem. Wasn't stationary for more than two seconds.

[chrisgixer]

Trims where within +/- 2 on both banks last I looked. Will check.

 Will repeat the scenario as well, and see what happens.

Not aware of Asking the car to do that before tbh.

[TheBoy]

No tick over. Jump in, start, drive off. Then probably two minutes of 30-40 limits, quick blast up to 70, then stop for the round about. Car in front pulls away, my turn, then the problem. Wasn't stationary for more than two seconds.

Before stopping, had there been any "unusual" engine speed/load (ie, idle) for any great length of time? As the trims would take a good few minutes to sort their life out if were way off.

Personally, I think its related to that on-off-on lag that we've seen before on the DBW V6

[TheBoy]

Trims where within +/- 2 on both banks last I looked. Will check.

 Will repeat the scenario as well, and see what happens.

Not aware of Asking the car to do that before tbh.

Trouble is, its what the trims were at the time

Long periods of "unusual" rpm/load can knock LPG trims way off, esp on the OBDII compliant cars.

[chrisgixer]

Absolutely nothing unusual about the journey. It was my morning commute. No tick over at all. Not even cold. Not frosty so didn't need to clean the screen.

[TheBoy]

Absolutely nothing unusual about the journey. It was my morning commute. No tick over at all. Not even cold. Not frosty so didn't need to clean the screen.

What about the previous journey?

[chrisgixer]

Absolutely nothing unusual about the journey. It was my morning commute. No tick over at all. Not even cold. Not frosty so didn't need to clean the screen.

What about the previous journey?

commute home was uneventful. No unusual traffic. Even had a bit of a play.

Good point though.

[chrisgixer]

As you say I think/guess it's related to the lag, but what's unusual to my experience of that is, apart from bending stationary, is the very gentle way it eventually pulled away. Bit like it was in third/snow mode, very slow and deliberate, except it was in first as you'd expect.

It certainly wasn't trying to replicate the pedal position at full throttle as I was asking for. I was completely over ridden.

[TheBoy]

What state are the throttle bodies in? If they are a bit gunky, and the throttle was slammed shut, then immediately reopened, if the servos struggled initially?

(though I don't think so, as much as I'd like to state cable throttles are superior )

[chrisgixer]

What state are the throttle bodies in? If they are a bit gunky, and the throttle was slammed shut, then immediately reopened, if the servos struggled initially?

(though I don't think so, as much as I'd like to state cable throttles are superior )

Nothing unusual going by the last time I had the bag pipes off. But probably haven't been cleaned since the last time the cam covers and breathers where done/cleaned.

I do wonder quite how gunked up a Dbw throttle needs to be before the motor can't shift it. I'd suspect an electrical fault first I think.

Suspsion is something in the software found the drivers inputs ...inplausible? Then decided to do the nearest sensible thing instead