Bad fuel economy in 20v

Matty104 · Post by **Matty104** » Sat Oct 20, 2007 7:37 am

hey guys, about a month ago i put a new oxy sensor in, and cleand plugs and injector cleaner all at the same tim to try eliminate the bad economy, as soon as the oxy sensor was it it ran a hell of a lot better, didnt run rich and got up to 470kms out of a full tank, and now all of a sudden its droped bak down to about 390kms on the same driving style. doesnt smell like its running rich at all anymore so seems like that oxy sensors fine, any ideas?

Matty104 · Post by **Matty104** » Thu Nov 08, 2007 8:01 pm

Grrrrrrr! · Post by **Grrrrrrr!** » Thu Nov 08, 2007 8:06 pm

Have you still the the cat in the exhaust? if thats clogged up it will hurt fuel economy.

Does it still have plenty of power (for a 20v) or does it feel a bit gutless?

Matty104 · Post by **Matty104** » Thu Nov 08, 2007 8:35 pm

na cats removed as ive got a aftermarket 2 1/4" system, stll feels the same power as its always had really ay, could it be a stuck thermostat?

matt dunn · Post by **matt dunn** » Thu Nov 08, 2007 10:30 pm

dont run avgas or any fuel additives at all?

HZRDIZ · Post by **HZRDIZ** » Fri Nov 09, 2007 7:49 am

gasman wrote:i only got about 400kms city driving in my blacktop with it running perfect with no errors or anything. driving like a nana as well

I'm the same - i'll be lucky to get 450km a tank... usually i will only get about 400km - 420km which i thought sucked - mayeb some are just more thirsty than others - have to get the exhaust done so hopefully that will make some sort of difference

Voyeur · Post by **Voyeur** » Fri Nov 09, 2007 11:45 am

540-560ks in mine. I have a pretty strick maintenance routine though. Exhaust sensors are cleaned every 5k at service, fuel and air filter every 10k service, i run iridium plugs, and warm the car up for 4 minutes every morning. Also i dont rape the car until it's fully warm. 20k to work 20k home every day, plus weekends. fill up every second sunday, and i only buy fuel from one station. Got 680k's on my last trip to Hamilton

barryogen · Post by **barryogen** » Fri Nov 09, 2007 3:16 pm

Matty104 wrote:as soon as the oxy sensor was it it ran a hell of a lot better, didnt run rich and got up to 470kms out of a full tank, and now all of a sudden its droped bak down to about 390kms on the same driving style.

re-read the early posts.

sergei wrote:Oh but when O2 sensor goes it is usually is a symptom not problem itself.
Otherwise you will have to replace it again in 1-3years (or sooner).
I successfully restored 10yo sensors with a butane torch.