lionkoala74

just took a road trip and realized my ralliart is guzzling gas, im getting about half the mpg i used to

lionkoala74

just for refrence i recently replaced the radiator with an aluminum high flow and replaced the thermostat with a new low temp one... also added a aem cold air intake and put in some ngk laser plat. plugs... not sure if any of that would have anything to do with it but like i said just a refrence... also i was considering running a fuel system service on it (supposed to restore fuel economy...) any thoughts on that?

CrAnSwIcK

iTrader: (5)

what's your mpg? what's your max engine coolant temperature?

what was your avergae speed? auto? manual? RPM at average speed? are you stepping on it? etc.

also having a cooler running engine is not really beneficial to the car, so having a more efficient rad, coupled with a thermostat that is not rated for the normal operating temperature of the engine could be causing issues that would effect your fuel economy...

knowing your fuel trims, AFR, and long and short term fuel economy would also help...

samterry1234

iTrader: (3)

ive noticed mine steadily going downhill for the past year or so. just had to replace my MAF sensor and I cleaned my throttlebody while i was working on it, but so far i've been getting more normal fuel economy.

$MIVEC$

Do you know whats your average MPG usually? Like Cranswik asked, Whats your current MPG?

This

Depending on the current fuel trim, assuming stock, the lower temperature of the engine could make you increase the mpg slightly. Proper combustion happens with the right amount of air, spark and fuel but this is also working along side the overall temperature and pressure(compression) on the engine. A very hot engine could cause pre-ignition but a colder than normal engine....could maybe adjust the fuel trim to have proper combustion?

You said you changed radiator, thermostat and spark plugs and a CAI....

Did you change those practically at the same time? Was your MPG better before this?

2006_RA

iTrader: (1)

What MPG were you getting before, what is the new MPG ?
Ditto to what the above guys said.

rickylancer

ok when i take trips it guzzles gas too bro but that is when i am going highway speed which is usually 75-80 it is at 3500 or 4000 rpm it doesnt do that good at american highway speeds when they test cars for mpg highway speed for them is 60-65 so if ur going above that ur gunna waste more gas bud.

CrAnSwIcK

iTrader: (5)

i think the biggest problem is the thermostat...the high flow radiator is just making it worse, the ECU and fan controller can only do so much...

rickylancer

true...

Darewood

I would suggest getting an OEM temperature thermostat. I know when mine was stuck open my temperature was around 140-150F and I lost about 6mpg! I was going to replace mine with a lower temperature one, but the research I found suggested it was bad and would cause issues down the road. Now I replaced mine with the OEM temp one, my temp is now 190F though. But the needle is sitting at the same spot as it was when the original thermostat worked. I never checked the temperature when it was working to see if 190F was normal, but it stays at this temp and never rises above it.

CrAnSwIcK

iTrader: (5)

190 is perfectly normal...it's in the optimal range...our OEM thermostat opens around 180, and is fully open at just a hair over 200.

RacerX-Ralliart

iTrader: (3)

I've been getting 22-25 mix freeway and city and I have a heavy foot the least amount I got was 17mgp all city.. I'll try to shift at 2500 Rpms and stay 65 on the freeway to see what mpg I get... Anybody else getting this mpg I'm thinking it's low but prolly because of my driving habits

2006_RA

iTrader: (1)

I average 24mpg.
Other people say that I drive fast.

Darewood

Thank you Cranswick I wasn't too sure if it really was alright, but I wasn't having issues with my car so I didn't worry.

My avg for gas mileage is about 28 for Spring till Fall. Once winter hits my mileage drops to about 23-24. I travel mixed highway with traffic lights at the end of my journey into work haha. This is also with my constantly on it. I'm sure if I would ease up a little I could squeeze some more mpg out of the car.

Also a little more with the OP, is there any update with you Lion?

lionkoala74

alright... definately took everything into consideration and i appreciate all the input... i was thinking lower temp thermostat and a cooler engine would be beneficial but maby not so much also i guess youre right i was kinda bouncing between 75 and 95 the majority of the trip and the gears are mad short so that makes sense too... anyway everything considered it was just too big of a difference so i hooked it up to a scanner (even though the check engine light wasnt on... i think it blew out) and got a low cat effeciency code which ive been told is definately the source of the problem... so im planning on replacing it... im thinkin either a high flow cat or maby more affordably just straight pipe then jus spot weld the heat shield from the old cat around it (for state inspection ).. any thoughts or has anyone gutted their cat?