What else can be done here...MPG gone to dogs :(

Well its been a bit over a year now and the damn accord still never made it back to its original fuel consumption stats. It all started with a running to lean code from a long trip and later followed by a few weeks with issues of a rattling cat. converter. Front o2 got changed with denso first time fit, and cat got changed about 2-3 months ago again with after-market as the previous after-market one wouldn't pass emissions.

Before 1 year ago i'd get constant 8-9L/100km (26.1-29.4 mpg). After the cat and o2 got changed mpg went down. Thinking a tuneup might've been needed all the below were changed but mpg was still crap at 11-12L/100km(19.6-21.3mpg). Now both o2 sensors have been replaced with OEM Honda bought sensors and mpg is still as the latter mentioned.

What has been changed and done since mpg started dropping
-Wires with NGK HE73
-Plugs NGK Iridiums
-Cap/Rotor (Aftermarket from rockauto)
-PCV Valve (OEM)
-Fuel Pressure Regulator (Aftermarket from rockauto)
-K&N Air Filter(Has been cleaned)
-Tire pressure is kept at 32.5-33psi all around.
-Car has been sea-foamed 3 times since it all started.
-Car does not burn oil
-Oil changed every 3000-4000km
-Tried running both Chevron/Techron additive and STP Fuel injector cleaner.
-ECT is at about 90-100C when car is warm.
-Long Term Fuel Trim is at about -7%
-At times i get the P1456 code for gas cap being loose(and it is loose somehow) but once tightened for a second time it doesn't come on again.
-TB has been cleaned.
-Grounds have been checked
-Battery is good
-No vacuum leaks
-Tranny fluid done once every year.

Some data(if it helps)
Idle
Long term fuel trim(%) -8
MAP(kpa) 26
Sparkadv(degrees) 11
IAT(C) 73
ETC(C) 97

2500RPM
Long term fuel trim(%) -8
MAP(kpa) 27
Sparkadv(degrees) 32
IAT(C) 71
ETC(C) 96

Monitors at idle
http://www.youtube.com/watch?v=7S1Ms4rLZPA
Monitors at 2000rpm, followed by o2 graph at 2000rpm then idle.
http://www.youtube.com/watch?v=Wj_MRHLFXi0
Opinions/Suggestons on getting 8-9L/100km again

http://www.6thgenaccord.com/forums/showthread.php?t=24598
http://www.6thgenaccord.com/forums/showthread.php?t=25899

Opinions/Suggestons on getting 8-9L/100km again

Re: What else can be done here...

change out your spark plugs to copper ones... iridium are not needed in the 4 banger

also, have u seafoamed the car?

Re: What else can be done here...

DarkSideAccord said:

change out your spark plugs to copper ones... iridium are not needed in the 4 banger

also, have u seafoamed the car?

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I actually had iridium in there since i bought it, hence changing them back to back with iridiums didn't seem to be the issue.

As for seafoam, yes since all this started its actually been done 3 times.

-Car has been sea-foamed 3 times since it all started.

Click to expand...

Re: What else can be done here...

have u checked your tire pressure or added anything inside the car?

Re: What else can be done here...

DarkSideAccord said:

have u checked your tire pressure or added anything inside the car?

Click to expand...

Yep tire pressure is 32.5-33 all round.
As for anything added. I have 2 toolboxes in the trunk but that have always been there since after the first week of buying it so couldn't be those

Re: What else can be done here...

Cmon gais...im running out of ideas lol. Only thing left i can think of is a leaky fuel injector or more then one but wtf, id think i'd get a code or something.

yeah, my gas mileage is garbage too, im lucky if i get 250 per tank on my 4cyl5mt ):

did you buy a brand new OEM sensor?

BadgerType said:

did you buy a brand new OEM sensor?

Click to expand...

Yep, since a lot of dealers and some techs told me that apparently Honda o2s and the ones that Denso sells to the public with the same part # are different.

Now both front and back o2s are oem honda.

PS. Video taken today of sensors readouts in first post.

i feel your pain. my issue is i smell fuel in the mornings and since it's almost winter im guessing the cold might have soemthing to do with it. but how much do you get on a full tank? assuming your tank is 17gallons right? when i fill her all the way i usually fill up to 15 gallons and get about 220miles...really bad but i do have a v6 if that affects anything.