2005 Toyota Check Engine

[NullByte]

I bought a 2005 toyota corolla ce from Hyundia about 3 months ago. About a month ago I had the check engine light come on, I hooked it up to a reader and it gave me the error p0171. I reset the message thinking maybe it was just a fluke. The message came back, so I decided to call Hyundia and get them to look at it. I purchased a warranty (Powertrain/Standard), so I wasn’t worried. They said that the Mass Air flow meter was slightly contaminated and they cleaned it. So I ended up having to pay $55 because my warranty only covers parts that are replaced. Well 1 day later here I am and the check engine light comes on again. I haven’t hooked it up to the reader again, I am pretty sure it’s the same error code. I called them again, and they are going to check it out again.

Should they charge me again if it’s a different sensor? I am not a car tech, nor do I know the walk and talk of how to handle repair shops. Has anyone had this problem with their vehicle? What can I expect the dealership to try to do? If it’s something that doesn’t need to be replaced should they charge me again, considering they didn’t do it right the first time?

[mikered30]

Dont have them pull the code at first, go to advance auto or autozone or some place that reads codes for free and confirm that it is the same code. What air filter is in the car? Does your engine rev above 3K RPM? It could be a leaky intake gasket, but you said you are not a car tech. There is a really easy way to check if it is leaking.


Print this out and take it to the dealer, although I am not sure what Hyundai can do with it because they are not toyota, and see if your car qualifies. There is also a tsb for the intake manifold gasket.

http://ww2.justanswer.com/uploads/sk...ap0445_441.pdf

http://ww2.justanswer.com/uploads/sk...rolla_0171.pdf

[scarney1988]

I didnt look it up but i believe P0171 is lean condition. If the same code returns, it then you have a few possibilities:

1)Unmetered air, or air your car's computer is not detecting, is entering the engine. Your Air/Fuel ratio sensor is detecting this imbalance and adjusting. Once the engine adjust so far (adding 30% additional fuel) it will trigger the CEL

2)Your Air/Fuel ratio sensor is reading improperly.

Its hard to say without being able to see the car. I would suspect number 1. If you want to look into it yourself there is plenty of information out there. If not, return to the dealer (after you already know what the code is). Your probably looking at intake gaskets or a whole new intake (plastic cracks). Possible a vacuum line is cracked, but not that common. No matter what, good luck.


Sean

[Tech1984]

Have you had some really chilly mornings at start up lately? The reason I ask is because we don't see this code (171) all summer.
But once the fall air temps get here, they come in regularly with the Corolla's.
Freeze frame data always tells me the code set on cold start ups.
What happens is the rubber intake gasket shrinks in cold ambient temps and causes a vacuum leak.
Once warmed up, the leak goes away.
The first thing suspected is the MAF meter. It gets cleaned or replaced, then you're back the next day. Sound familiar?

[NullByte]

Thanks for the great information guys; I truly appreciate your kindness.

Ok the light was on for the last 2 days (2 days since being "repaired' and being reset). I woke up this morning to go do some things and the light was off. So I hooked it up to the reader and it's still showing p0171. I deleted it out of the cars memory, and then read it again and it still shows error p0171. I know the light works because I see it come on when I first turn on the car (all the lights come on, kind of like an initializing process) Why would the error message keep showing and the "check engine light" not be on no more?.


Tech1984 "The first thing suspected is the MAF meter. It gets cleaned or replaced, and then you're back the next day. Sound familiar?"

They cleaned my MAF, charged me $55, and sent me on my way. I didn't even know what a MAF was till 2 days ago. What can I expect next, and is it something they replace or maintenance?

What can a dirty MAF do to a vehicle?

[Tech1984]

First off, you may not see the MIL but the code can still be in stored memory. This is called "pending code"
It works on a 2 trip logic.
The second time after clearing, the ECM sees the same fault a second time and triggers the MIL on.

This is where you need to "aggressively discuss" that you shouldn't have to pay for a same repair twice.
I'm sure they have All Dada or something to research tech bulletins, and it's right there in front of them.
So....it was a wrongful diagnosis. Nothing you did.

Lastly, think of the MAF sensor as the beginning of your engine management system. It reads and sends air mass to the vehicle ecm.
At the end of the chain is the downstream 02 sensor what is seen coming out the cat.
A dirty MAF will tell the ecm GO Lean! But it wasn't the case in this situation looks like.

[tixxit]

My wife just had a similar problem recently. P0171 came on, checked the MAF, cleaned it, reset the CEL, and it was good for about a week then came back on. However, there is a TSB about it and it suggests replacing the intake manifold gasket . It is about $10 - part # 17171-22060. I just replaced it today. Takes about 30min if you do it right the first time

If you do it yourself, word of advice: you don't need to take the coolant/water bypass hoses off of the throttle body (and so you don't need to change your coolant). Just leave them connected; there is enough wiggle room to take the manifold off, put the new gasket in, and put it back on. Also, there is a hose that connects behind the throttle body and is very easy to miss when putting the manifold back on.