96 I30 gas mileage

[Mayhem_J30]

My brother in law's I30 is getting severely low gas mileage. With OBDII I would expect the usual suspects to pop a CEL; O2 sensor, knock sensor, MAF.

She's getting up there in mileage, approaching 130K miles. Only premium fuel is being used. Any ideas? Am I right in expecting the ECU to catch one of these sensors failing if that is in fact what is going on?

[qship96]

what is severely low?does he idle more in winter to warm up the motor?give us the details!where is car located?

[elwesso]

Id suspect that things need cleaning, and a good tuneup. The sensors can be hanging on by a thread and still giving a signal, but not working optimally....

Id say reaplce the o2s, as those are nearly shot, and clean things up like the MAF, TB, etc....

[Mayhem_J30]

He's getting about 15mpg. Should be at least above 20 normally.

I cleaned the TB real good last year for him.

If you check my location I'm in Louisville and it's not exactly winter here anymore.

O2 sensors is what we'll end up replacing, but before dropping the money on it I feel like we should be for sure. There's no CEL so that had me lost.

[Q451990]

The O2 sensors can be sluggish enough that they'll cause MPG reduction, even without setting off the CEL - even on OBDII models.

They may even check OK with the lean/rich flip test with the ECU in diagnostics. I replaced the one on my truck for just this reason and got a few MPG improvment, getting back in the 20s. Still seems bad for a 2.4L 4 banger, but it's geared for torque and it doesn't hit the sweet spot until about 2000-2500 RPM so I'm always reving it like I stole it... the Q will make one very impatient with other cars.

Heath

[AntiIdTheft]

What are average MPG for '96 I30 V6, city and highway?

Does the octane really matter that much?

How can you tell if Octane is too low?Thanks,JoeTulsa, OK144 K Miles and ticking

LQQKING for RIGHT cornering lamp assembly for 1996 I30 which is next to the fog light in the bumper.

[Q45tech]

Don't confuse the 1985 EPA mileage standards criteria with the real world unless you follow their test proceedure. Never exceed 60 mph and maintain anverage speed of 55 mph.......rural highway no passing no stops.

If the knock sensors detect knock and reduce the ignition advance expect a 10% drop in efficiency [cruise mpg].

[epmeyer]

I have a '96 I30 and a '97 I30t. The both get 21 to 23 mpg around town and 28 on the road.