Mechanics

GETTING TERRIBLE MPG BUT HAS BEEN VERY WELL TAKEN CARE OF

2002 Hyundai Accent • 103,000 miles

I have an 02 Hyundai accent 1.6L automatic with 103,000 miles. I have replaced. Both o2 sensors, plugs, wires, all fluids and filters, MAP sensor, flex pipe, ran sea foam, replaced fuel cap, and PCV valve. I'm getting terrible gas millage, bad acceleration, and slightly over revving. I get about 20MPG no matter where I go, If not worse. BUT if I reset my PCM the car runs like new for 80 miles. Please help me. I'm out of ideas.
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Weaponhead
July 26, 2012.



Are there any codes in the system? If there is, give us the numbers.

I would have the cat converter check for backpressure.

Roy

ASEMaster6371
Jul 26, 2012.
No codes right now. Had randome multipul misfires, and o2 sensor codes. I took care of those issues.

Tiny
Weaponhead
Jul 26, 2012.
Those code numbers would have helped. Code numbers never identify bad parts, just failed systems.

Have you had the injectors professionally cleaned?

Roy

ASEMaster6371
Jul 26, 2012.
No, I have only had the car for a month. And I am getting pressure out the tailpipe from what I can tell.

Tiny
Weaponhead
Jul 26, 2012.
Thats not a test, you insert a gauge into the fron o2 sensor hole to measure backpressure

Roy

ASEMaster6371
Jul 26, 2012.
Alright. What are your thoughts on my problem? What should my next actions be?

Tiny
Weaponhead
Jul 26, 2012.
Testing as I suggested. You need to test to find the failure, then replace the failed parts.

Why dont you get a shop to at least diag it for you and then you know what has failed and you could replace the needed parts.

Roy

ASEMaster6371
Jul 26, 2012.
It seems like that is what I'm going to need to do at this point.

Tiny
Weaponhead
Jul 26, 2012.
Good luck

Roy

ASEMaster6371
Jul 26, 2012.