I am a turbo setup, however i have recently lost 3 mpg. Seems like since the cold weather but thats an assumption. Havent noticed a performance loss. I just need all causes of losing mpg on stock f23a1's or if you know turbo even better.

 

now i do not remember if the 6th gen has a fuel pressure regulator by the fuel rail or if it is a in tank style attached to the fuel pump, but if it the type like the 5th gen where it is by the fuel rail, the regulator could be defective and be pushing too much fuel. you could have leaky fuel injectors when it comes to the sealing o-rings on them, or one or more of the injectors could actually be malfunctioning and staying open. you could even have a vacuum leak or a intake manifold gasket leak which makes the engine run lean obviously and the computer is compensating for it by turning the mixture hella rich. or you could have a lazy 02 sensor and telling the computer the exhaust coming out of the engine is lean, when it may not be, thus making the engine put more fuel in. and finally, maybe check your tune. maybe it could be off. hope some of this helps.

 

Hey I posted this in response to your other post in the other thread, but i'll put it here since you started your own thread. I had a turbo accord as well, and here is what I think could be possible...

"Idk if FL will use a winter gas mix. You guys don't get as cold as we do in New England haha. For you, maybe it's that your car's IAT sensor and MAP sensor are noticing an even colder/denser amount of pressurized air coming in and your ecu is adding a little more gas than usual to keep things matching with your tune. I'm assuming you were tuned on a warm day in FL so the air wasn't as cold.

OR, maybe it's just typical stuff like your air filter, ignition related items, primary o2 sensor. "

I would check your basic stuff first, b/c unless you have can tune, there's not much you can do. Are you watching your AFR gauge? What's that telling you?

 

thanks for the post i actually have another one in the turbo section but no replies.
Yeah my afr ratio has been overall higher. sometimes hitting in the 14's briefly while cruising breifly. so i am having leaner condtions then usual. if i had to say what i noticed different. However i am not having any hestitation or performance issues.

 

Well, I would check basic maintenance first. I really think this is just cold weather + some routine maintenance. It's not like your tune changes by itself. Maybe you can disconnect your battery and see how the ecu re-adapts to the climate change.

Jw, is it on the stock fuel pump?

 

I just realized you said it would hit 14's in normal cruising. That doesn't sound bad to me. My car would see 15's during normal cruising. That's just part of good fuel economy. If you've been seeing much richer numbers under partial throttle driving, maybe you washed out the piston rings and gas is getting past them and into your oil. I doubt that's happening to you because you'd notice the smoke haha...Bottom line, you should only see rich numbers under heavy throttle.

 

14 is not bad. in fact 14.7 is the stoichiometric ratio, the perfect air to fuel ratio. there is absoultely nothing wrong with that. under heavy throttle, considering you are boosted, i would not mind a little extra fuel.....just to avoid the knock and potential hazard of running lean.

 

maintence should be fine i keep up with all that, your correct the tune shouldnt change i have aem standalone. ill try the battery, not a stock fuel pump. its a high preformance 255lph.

 

You could try reading your spark plugs after a drive. Take pics of what they look like and post them up.

 

before this i was lower in the 13's it seemed, i know 14's is good on N/A motors but on turbo the numbers should be lower correct? I know in an old automotive encylcpedia it stated turbocharged cars need to be around 10-12 and other people advised the same. Maybe they are just refering to under load/acceleration?

 

i will do this thankyou! It will be tommorrow though.

 

That's somewhat correct. I was under the same impression when I first finished my turbo build and went in for a tune. However, my tuner and along with others I know that have done tuning, agree that lean afrs are perfectly fine for just cruising around town/highway/etc. It's part of fuel economy. Think of it this way, when you're driving around normally at partial throttle, your car is only under vacuum, just like an n/a car so there is no need to go rich. I drove my boosted accord around and my afr's would be around 14's and 15's regularly. But, when I started to spool that's when afrs got richer. When you start spooling and making boost, that's when you increase combustion chamber heat and pressure. Once the temps and pressure are up in the chamber, that's when you want rich afrs.

I would go search for someone who is a reputable tuner around your area for a retune. If you trust your current tuner, or if you tuned it yourself, bring up these points and see what he has to say. Turbo honda's demand more fuel, but there is no reason for us to get gas mileage in the teens for a dd.

 

14.7 is the perfect afr for idle.

 

Very good info man thankyou. This makes complete sense. I guess im flipping out on the afr's for no reason then. I have been dd on the same tune for bout 1 1/2yrs. And i have had the 20 mpg for awhile until recently in the cold. So thats where im puzzled specially when im not really having a performance issue.

 

i sit at 12-13 haha. not good.

 

Ya, I don't think you have any serious issues. Obviously we both know your tune can't change on its own. If you want to try and get better mpg's, my suggestion would be to go over stuff like cleaning your air filter, new o2 sensor, check your tire pressure, plugs, wires, cap, and rotor. I'm guessing your plugs are bkr7e's. Some people switch those out every oil change since they're so cheap. Their life is shorter than the typical suggested oem plugs.

I would go get re-tuned by a trusted tuner.

 

Ya that's very excessive. Get that changed asap.