Fuel to mileage ratio
19-Apr-2010, 04:05 PM
#49
Senior Member
Join Date: Jan 2008
Location: Mississauga
Posts: 1,672
If you have a crack in the catalytic converter , why not just replace it?
It sounds to me that you already know what the main problem is , you just need to replace ( you ll have to do it sooner or later anyways) and then If you are still getiing bad mileage you can start replacing other parts
Replace your cat first
I can think of two other things making your car run poor
Fuel Pressure Regulator Failure Symptoms:
Engine runs rough
Engine stumbles or sputters
Engine runs very rich - black smoke from the exhaust
Engine will not start
Engine starts but stalls shortly after startup
Noisy fuel pump
Noticeable decrease in fuel mileage
and maybe the thermostat
But i wouldnt change any of those above until i get my cat fix ..
It sounds to me that you already know what the main problem is , you just need to replace ( you ll have to do it sooner or later anyways) and then If you are still getiing bad mileage you can start replacing other parts
Replace your cat first
I can think of two other things making your car run poor
Fuel Pressure Regulator Failure Symptoms:
Engine runs rough
Engine stumbles or sputters
Engine runs very rich - black smoke from the exhaust
Engine will not start
Engine starts but stalls shortly after startup
Noisy fuel pump
Noticeable decrease in fuel mileage
and maybe the thermostat
But i wouldnt change any of those above until i get my cat fix ..
19-Apr-2010, 04:12 PM
#50
Senior Member
Join Date: Dec 2007
Posts: 356
Your car has 11.9 US Gal fuel tank. At 30mpg (low fuel mileage for that car given 12 years old; new is 29-36mpg) you should be getting close to 357 miles = roughly 570kms per tank. Best bet is change the cat and see from there....but I doubt it will make that much difference.
19-Apr-2010, 04:55 PM
#52
Senior Member
Join Date: Dec 2007
Posts: 356
Just for shi**s and giggles, if I was you I would pull the spark plugs (which you said you recently changed) and have a look at them. If your engine is not running properly or your fuel/air mixture is off, they will tell you.
19-Apr-2010, 04:59 PM
#56
Junior Member
Thread Starter
Join Date: Mar 2010
Posts: 24
nope i got all of them checked and replaced...it has to be the cat but i mean there's a big difference between the mileage i should be getting and the mileage i am getting...don't know if the cat will make the whole difference
19-Apr-2010, 11:10 PM
#58
Inactive
Join Date: Sep 2007
Location: Where my car is.
Posts: 5,460
If the O2 is constantly getting a false reading, a lean reading (since your exhaust is leaking out so it can't get a proper sample to read), then the ecu will try to compensate until it gets the proper reading. It's probably dumping loads of fuel in to compensate.
Even if you welded up the crack/hole in the cat/manifold as a temporary fix, I bet you'd see a significant reduction in fuel consumption.
