So, today i was driving and my car through a CEL (Check Engine Light) with code P0174...

I called Acura, and they said it means "Running Lean" and he suggest it was a poor octane fuel. Now, i ONLY use Super +

I filled my Tank up on Thursday (4 days ago) , and the light just came on when the tank reached half empty. Service rep told me to just drive the car, use the gas, and re-fill

I was wondering, has anybody else had this problem? My 06 TL ran lean (according to dyno) but never through a CEL for it. This is an 08, and the AcuraLink gave me the code of P0174

Any comments from anybody?

 

oh, and FYI the code means Running Lean in Bank 2... saw another thread with a member having this problem, but he had it over and over again. this is my first.. i will try to clean my MAF sensor.. and hope that does the trick

 

well, i cleaned the MAF sensor, and reset the ECU.. CEL is off and no code yet... gonna go drive her for a while and see what happens. still have half of tank of this "bad" gas

nobody else experience this issue??? strange....

 

I don't see the connection to running lean on only one bank and a bad tank of gas. And by bad gas, I'm not talking about octane. Octane has no effect on the A/F. Could be a bad 02 sensor.

MAF sensor? Do the 07s have this?

 

well, i cleaned the IAT sensor, and the other sensor on the throttle body.. which i thought was to be the MAF sensor

The acura service rep just told me to run the gas out and get another tank... i was too impatient, so i pulled the battery... cleaned the two sensors, hooked up the battery, and let her run.. no CEL after that... should i not have done that?

either way.. drove the car for about 5 miles tonight, no lights. gonna use it for work tomorrow, so i'll see what happens...

 

No harm I'm sure. You might be getting a lazy 02 sensor. Sometimes a few hard runs will wake it up temporarily. If you drive your car hard and it is an 02 that's the problem, it's less likely to throw a code again.

 

i usually dont drive it toooo hard, not yet anyways =)

im gonna let her run for a couple days, get a new tank of gas tomorrow and see what goes.. so far, no CEL

 

I got CEL & both P0174 & P0171 (on a 07 TL-S if it makes a difference)- any clue on what the P0171 might be?

Thanks!

Lily

 

p0171 is bank 1 Lean and p0174 is bank 2 lean.

 

Wow Lily... 2 years, and only 2 posts !! lol

It could mean a few things.... you used a low octance gas (regular), your MAF sensor is dirty, or your o2 sensor might be going haywire....

i reset my ecu, light it is gone.... been off for a couple of days

 

Wouldn't a CEL be something that warranty might be addressing? You clear the code and they have no record of the issue?

You paid through the who who for warranty .. why not use it?

 

yea. but ive got a CAI, ur pulley and exhaust already.. so i fixed it myself... i think it was lousy gas... ill do some dyno pulls soon to see how the car is performing

 

lol I like to pace myself! (Actually I had an acura then got rid of it around that time and now have an Acura again)

Didn't put in regular gas- Scheduled an appointment for next Wed- we'll see what they say.

 

I had the same problem about a month ago.
I had put about half a tank and when it was on low thats when the light came on. But the next day when I turned it on the light didnt come back on. So i went to put gas in that morning and same thing happened so I stopped going to that gas station and the light hasnt come back on again.

 

usually bank codes, are caused by lazy or biased oxygen sensors.

fuel trim does are for both banks..

id have the tech datalog and set up a snapshot so when the cel happens it catches it.

im sure its an oxygen sensor, although i have seen some fuel trim problems with gas.

 

i have the same problem, po174 bank 2 too lean cel, half tank, 91 oct fuel. Car seems to run ok otherwise. Did you guys have your cel's come back on after you cleared them or did you have to start replacing 02 sensors etc?

04 TL 6mt 89k miles

 

tech7427: you think it may be bad gas clogging up bank #2 fuel rail? maybe the fuel flow is somewhat slowed...how bout running the tank empty with a bottle of pro-honda top engine cleaner in the tank? or maybe along with some techron...

 

04 148K miles, p0174 came on today. Ive been using QT gas (quicktrip) and I drive my car hard. I would love to know what I need to do so I can pass emissions next week

 

I had this happen about 2 weeks ago. No obvious symptoms when driving other than a CEL. It went away the next morning and it came back this morning. What I've gathered from this thread is, check/replcae O2 sensor or try different gas?

 

This is a long shot but not too far out in left field.

Did you happen to buy fuel at an older station, a station that doesn't move a lot of product, while a station was having its tanks filled by a delivery truck, an off brand, or a combination of any of these? Reason I ask is there is the off chance possibility you could have purchased tainted fuel. Consider running a quality fuel system cleaner through your engine (read the directions). Either Chevron Techron or Sea Foam (the best) are good products. Again, follow the directions and don't get injector cleaner... get a fuel system cleaner.

Then always buy a reputable brand of fuel from a newer station that moves a lot of product and don't buy when they are taking on re-fills from a truck.

 

I had this happen to me too, but I didn't put regular gas. I put in premium octane 93 gas from Hess. I got both the P0171 and P0174 codes from Acuralink. I called and went to the dealership and they told me that my valves might have to be readjusted. The guy at the dealership seemed so sure about it too. I asked how much they charge for that and he said $400-500. And supposedly this isn't covered with the warranty. Kind of fishy.

 

A bro what's going on speaking of that problem I had the something I
Went to valley stream Acura and I got a software updated that's all u need. Just finish 5 mins ago.

 

You wouldn't be running lean on both banks without you noticing a difference in the drive style or fuel consumption.....trust me. I had this happen to my '04 and the dealership refused to believe me when I told them it was a bad O2 sensor, until I came back a third time. By then, they had replaced ALL of my fuel injectors under warranty and a week later the light came back on. They replaced the O2 sensor, problem NEVER occurred again.

 

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Then there's those occasional unscrupulous stations that'll pump lower octane gas out of the Premium nozzle in order to make more $$. Rare, but it DOES happen.

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I pulled a po174 only code today on my 04 MT. Where is bank two located? How many o2 sensors are our cars?