Toyota Avalon Question

downsouthSeptember 20, 2006

Our 1998 Avalon has 111,000 miles. We are getting about 20 MPG and we used to get 26-27 MPG. We have already replaced the spark plugs, have two new fuel sensors, have a new air filter and I keep air in the tires.

What could be the problem or what else might need replacing?

Thanks, Bill

Thank you for reporting this comment. Undo

I forgot to ask if cleaning the fuel injectors will improve the gas mileage.

thanks, bill

    Bookmark   September 20, 2006 at 10:54PM
Thank you for reporting this comment. Undo

It should help by cleaning the injectors. I would suspect the oxygen senser. If it is not working correctly the injection system will not send the correct amount of gas to the engine, causing it to run rich.

    Bookmark   September 20, 2006 at 11:06PM
Thank you for reporting this comment. Undo

I meant to say oxygen sensors have been replaced instead of fuel sensors, just this summer, two of them.

Do you know how many sensors an Avalon has?


    Bookmark   September 21, 2006 at 12:03AM
Thank you for reporting this comment. Undo

I took the car to NAPA today and they run a diagnostics test on it. Everything came back fine, the spark plugs, wire, oxygen sensors, nothing showed up in the computer as being wrong. They could not fine anything wrong except we've been putting 10w30 oil in it and they said it should be 5w30 for Toyotas. The front tires were a little low, 25 instead of 32.

I let them do some type of addictive which is supposed to remove carbons or something like that. It's supposed to make your car like new again. The guy said he did it to his Honda and he gets 3 more miles per gallon. It cost me $90, and something I probably could have done for $20. Hope this helps. The tires need to be rotated and I'll get to that next week.


    Bookmark   September 21, 2006 at 6:49PM
Thank you for reporting this comment. Undo

How did you make out after what you did (additive), Bill? Does the vehicle seem to lack power on hills and when accelerating? You can have mileage and power problems without any "check engine" codes showing up when the catalytic converter is blocked. This happened with my '02 Grand Prix at around 102K miles, right after tune-up with wires and some other services. At the time the dealer garage suggested the "de-carbonizing" that you had done but I didn't do it.

    Bookmark   September 28, 2006 at 9:28AM
Thank you for reporting this comment. Undo

The tyres would do that. Also if you're carrying something heavy in the boot.

Obviously you change the fuel filter at the specified intervals ? On some cars the injectors are not designed to be cleaned with injector fluid.

    Bookmark   October 11, 2006 at 1:37AM
Sign Up to comment
More Discussions
2004 Madza Tribute Catalytic converters
My daughters 2004 Tribute would not accelerate and...
dump my buick rendezvous?
Do you know the Buick Rendezvous? Mine has been outstanding...
Honda Accord 2014 or 2013 navigation
I'm looking at a 2014 Accord and wondering whether...
Cost to replace a 99 Buick head Gasket
My grandson 99 Buick blew a head gasket after the thermostat...
Tire Question
I have a 2007 Honda Ridgeline with 13,000 miles (yes,...
© 2015 Houzz Inc. Houzz® The new way to design your home™