P+G doesn't work on my VW - Fuel Economy, Hypermiling, EcoModding News and Forum

robchalmers · 07-01-2009, 04:56 AM

On my last thre commutes I've Been trying out Pulse n' Glide and it doesn't seem to want to work with my Polo - doing it between 65-55mph (go below 55 and you'll p*ss off the British truck drivers!) the car labours on restart as if its running VERY rich, it doesn't matter if I do a key restart or bump ignite. I have given it the benefit of the doubt even though my fuel guage has been dropping scarily fast.... might just stick to Constant/DWL/Drafting

SVOboy · 07-01-2009, 05:29 AM

Quick answer: You are driving to fast for P&G to work. It probably would do just fine from 20-30 mph,

robchalmers · 07-01-2009, 05:47 AM

Ah.... simple answer! thanks - sadly though truck drivers get pee'd if you drive incosistently around about their limiter speed (56mph) - so i don't want to risk going any slower really.

Fringe benefit though - Aero mods 'should' have more of any effect at the higher speeds I commute at!

SVOboy · 07-01-2009, 05:49 AM

Yep, I would aeromod and stick with dwl on the highway, it is what I do, at least.

vtec-e · 07-01-2009, 12:13 PM

Hi rob.
Have you tried p&g with the engine on? You could have fuelling issues when it starts maybe? Could it also be the case that you were too heavy on the throttle during the pulse? I'm just throwing ideas out there so feel free to put me straight! I'm guessing you don't have a scangauge so you have no readout of the engine LOD to pulse properly. Although seat of the pants works well for me.....

Best of luck.

ollie

robchalmers · 07-01-2009, 12:27 PM

nope no scan guage, I plateau'd back the throttle before cutting the spark, my friend say it might be the simple electronics the dub has in that it knows its moving from the speedo but isn't sensing combusted gas at the lambda so chucks more and more fuel in - then when you restart it runs rich til it settles out again.

The Atomic Ass · 07-01-2009, 09:28 PM

If you're just cutting spark you won't see much/any savings. You guess correctly, when the engine loses power the computer tries to compensate, and ends up dumping more fuel into the engine.

roflwaffle · 07-01-2009, 10:37 PM

Quote:

Originally Posted by robchalmers

Ah.... simple answer! thanks - sadly though truck drivers get pee'd if you drive incosistently around about their limiter speed (56mph) - so i don't want to risk going any slower really.

Trucks over there have a 56mph limiter! Jeez... I get passed by 'em if I'm only doing 70mph in the slow lane over here.

robchalmers · 07-02-2009, 12:57 AM

Yep and they're on allowed to use two of the three lanes too!

Piwoslaw · 07-02-2009, 02:07 AM

Quote:

Originally Posted by roflwaffle

Trucks over there have a 56mph limiter! Jeez... I get passed by 'em if I'm only doing 70mph in the slow lane over here.

I believe that truck speed is limited to 80 km/h in the whole EU. But... even though Polish laws prohibits trucks from going over 80 km/h, and states that they must have a speed governor, I often can't catch up to trucks when I'm going 100 km/h.