Volkswagen Forum Volkswagen  
VW Forum  

Hesitation, bad gas mileage = O2 sensor?

  Printable Version
Volkswagen >> VW MODELS >> Volkswagen Golf >> Hesitation, bad gas mileage = O2 sensor? Page: [1]
Login
Message << Older Topic   Newer Topic >>
Hesitation, bad gas mileage = O2 sensor? - 3/14/2007 9:00:39 AM   
Schmitty


Posts: 9
Joined: 2/21/2007
Status: offline
This is on an 85 Golf.  I think my O2 sensor is bad, I'm getting really bad gas mileage for having a Golf (probably 20-25 mpg, depending on type of driving), it seems like there is a lack of power during highway driving, and just an overall "lack" of power for a 2000 lb car with 100 horses behind it.  it has the 1.8L 8v engine.  The sensor is 20 bucks at the local parts store, so it's not a problem to get one, I just want to try and narrow the problem down.  Thanks!
Post #: 1
RE: Hesitation, bad gas mileage = O2 sensor? - 3/15/2007 11:13:32 AM   
codyt

 

Posts: 8
Joined: 3/13/2007
Status: offline
yes, a bad o2 sensor CAN make you have bad gas mileage. If its bad it will tell your computer to mix the air/fuel wrong and CAN make your mileage go bad. Im not a professional but i do work on cars quite a bit so this is just my opinion.

(in reply to Schmitty)
Post #: 2
RE: Hesitation, bad gas mileage = O2 sensor? - 3/30/2007 7:43:31 PM   
gsarvey

 

Posts: 2
Joined: 3/30/2007
Status: offline
I have a 1985 VW Golf and I am having terrible problems with hesitation, rough running and refuses to idle. All of this happens most of the time but not always. I've had one shop work on it for a couple of weeks. It now has a new distributor, cap, rotor, plug wires, coil, plugs but to no avail. They decided it was a fuel injection problem so we ran some fuel system cleaner through it which just seemed to make matters worse. I still think it's ignition. When I connect a timing light up the flashes are intermittent on three out of four plug wires. They even seem to be intermittent on the coil wire. It is fouling the plugs and spits black smoke. I'm now thinking it may be the electronic ignition control box but I saw your message about the O2 sensor. Did you change it and did it fix your problem? The cars not worth much and I hate to keep throwing money at the problem.

(in reply to codyt)
Post #: 3
RE: Hesitation, bad gas mileage = O2 sensor? - 4/8/2007 1:16:59 PM   
gsarvey

 

Posts: 2
Joined: 3/30/2007
Status: offline
As I stated in an earlier post I've been having terrible problems with my 1985 Golf 1.8. It was running rough, refusing to idle and sometime running on what seemed like one cylinder. I spent over $300 with one shop and it only semed to be worse. Well I finally solved the problem myself. It is now running better than it has for the past year. Most of the ignition system has been replaced and I'd run a bottle of fuel injection cleaner through it but all for naught. I finally decided to check the vacuum system out. I found the vacuum accumulator was leaking so I block it off and then replaced all of the vacuum hoses, including the ones to the air box. Voila. It didn't fix it immediately but after a four mile run to the dog park it started running better. By the time I got home it was running really good. It now idles and I can't believe how well it's doing. With the exception of initial start up, where it runs a little rough it smooths out quickly and goes like a Rabbit. I'm pleased, my dogs are pleased and I can't believe what $4 worth of hoses did for it.

(in reply to Schmitty)
Post #: 4
RE: Hesitation, bad gas mileage = O2 sensor? - 4/28/2008 4:30:51 PM   
Kyo_clone

 

Posts: 21
Joined: 4/28/2008
Status: offline
wat if ur car isnt throwing the code for the o2 sensor? should u still replace it ? i got bad gas mileage to ..... i know my car leaks coolant could that be the problem?

_____________________________

98 VW Jetta Vr6 Custom cold air intake

(in reply to gsarvey)
Post #: 5
RE: Hesitation, bad gas mileage = O2 sensor? - 4/28/2008 4:46:48 PM   
bagel


Posts: 1024
Joined: 8/16/2005
Status: offline
no no coolant won't make you have bad gas mileage, unles it over heats real bad..ha ha.  Yea you should every so often replace them, not as often as plugs, but ya know say 50,000 miles?  I dunno for sure, just guessing.  SO try that and if not let us know?  What does your engine code say?

_____________________________

'00 Jetta VR6 GLS 12V 2.8L
Magnaflow Exhaust
Custom Cold Air Intake
Eurosport Underdrive Pulley
GIAC Chip
Diamond Mesh Grill--Front
Smoked Euro Tail Lights
18" ADR Rims On Toyo Proxes
Pioneer Deck, 2400W Rockford AMP, 2-12" Alpine Type

(in reply to Kyo_clone)
Post #: 6
RE: Hesitation, bad gas mileage = O2 sensor? - 4/28/2008 5:26:20 PM   
Kyo_clone

 

Posts: 21
Joined: 4/28/2008
Status: offline
my car isnt throwing any code..... but i havent changed it since i got the car.... i got it used so i dont know if they changed it... Should i change it even if my car isnt throwing the code?

_____________________________

98 VW Jetta Vr6 Custom cold air intake

(in reply to bagel)
Post #: 7
RE: Hesitation, bad gas mileage = O2 sensor? - 4/28/2008 5:52:15 PM   
bagel


Posts: 1024
Joined: 8/16/2005
Status: offline
mmmmm if you're having engine trouble, or lack in power or anything like that then prolly yea, it would be a good idea cause like you said, you dunno if it was ever done.

_____________________________

'00 Jetta VR6 GLS 12V 2.8L
Magnaflow Exhaust
Custom Cold Air Intake
Eurosport Underdrive Pulley
GIAC Chip
Diamond Mesh Grill--Front
Smoked Euro Tail Lights
18" ADR Rims On Toyo Proxes
Pioneer Deck, 2400W Rockford AMP, 2-12" Alpine Type

(in reply to Kyo_clone)
Post #: 8
RE: Hesitation, bad gas mileage = O2 sensor? - 4/28/2008 6:05:35 PM   
Kyo_clone

 

Posts: 21
Joined: 4/28/2008
Status: offline
i think i should cause my gas gauge wasnt working right for a while..... i had to start putting gas adictives ...... but i getting real low gas milage.....my car shakes when takeing off from first gear and the lights dim down a little ..... what could that be?

_____________________________

98 VW Jetta Vr6 Custom cold air intake

(in reply to bagel)
Post #: 9
RE: Hesitation, bad gas mileage = O2 sensor? - 4/28/2008 6:19:51 PM   
bagel


Posts: 1024
Joined: 8/16/2005
Status: offline
lack of power...somewhere in the electrical system.

_____________________________

'00 Jetta VR6 GLS 12V 2.8L
Magnaflow Exhaust
Custom Cold Air Intake
Eurosport Underdrive Pulley
GIAC Chip
Diamond Mesh Grill--Front
Smoked Euro Tail Lights
18" ADR Rims On Toyo Proxes
Pioneer Deck, 2400W Rockford AMP, 2-12" Alpine Type

(in reply to Kyo_clone)
Post #: 10
Login OR Register now to post a reply to this forum topic.
Page:   [1]

 
Volkswagen Forum >> VW MODELS >> Volkswagen Golf
Jump to:

Featured Sponsors

Advertising Info

Top 10 Posters
bagel1024
joelzy646
jsd368
smokin dog286
patrick210
heavenly_bla204
jrailer177
emagdnim131
p_mister124
joenewton07124

New Vendors
AMSOIL - Performance Oil Technology
GetCoolParts.com
K&N Engineering, Inc.



Volkswagen Forum .com is not affiliated with or endorsed by Volkswagen AG.