[rqc]

Got a check engine light and the car seems to be running on reduced power. Took it to AutoZone and they said they weren't getting any Volvo specific codes. It looks like the ODBII code was P2178. For other brands, it looks like that is "too rich off idle - right bank."

I have an appointment at the closest dealer in a few days. Our dealer closed and now the closest one is 40 miles away. I'd like to get some idea of what might be a likely cause.

Fuel pressure? Emissions? MAF?

 

[ZenZone]

Re: Check Engine Light (rqc)

Quote, originally posted by rqc »

Got a check engine light and the car seems to be running on reduced power. Took it to AutoZone and they said they weren't getting any Volvo specific codes. It looks like the ODBII code was P2178. For other brands, it looks like that is "too rich off idle - right bank." I have an appointment at the closest dealer in a few days. Our dealer closed and now the closest one is 40 miles away. I'd like to get some idea of what might be a likely cause. Fuel pressure? Emissions? MAF?

rqc, Suggest you check for an air leak on your charge air pipe connections. P2178 "too rich off idle" indicates you are getting more air than usual causing the "rich mixture" condition. You should be able to see it by using a smoke machine - parts store should sell something to test the connections. Reseal the connections with an appropriate silicone compound - someone else may have a better suggestion on getting a good seal.

Hope that's the solution.

 

[ibanezplayer]

it won't be caused by getting more air than usual, it'll be caused by loosing air between the maf and the o2 sensor.

If there was air entering the system it would lead to a lean mixture.

 

[JoeLvo]

Re: (ibanezplayer)

Quote, originally posted by ibanezplayer »

it won't be caused by getting more air than usual, it'll be caused by loosing air between the maf and the o2 sensor. If there was air entering the system it would lead to a lean mixture.

+1

I would recommend taking it to Volvo and asking them to scan it for you. If they charge you, it will be $100 probably (interesting that Autozone has better service than Volvo, but I digress). Reason being, is that an OBDII scanner will NOT pull Volvo codes, so the guy is right in saying he didnt get any Volvo codes, but that's because he *can't* get Volvo codes. The Volvo specific code may direct you to exactly where the problem is, if you're lucky.

I would do this only after a close visual inspection of the intake tract/vacuum lines, because you may find something. Although running too rich strikes me as a situation that would require a faulty sensor of some kind, as a leak would cause a lean condition, and fuel is metered by the ECM or some such contraption, based on sensor inputs.

 

[ZenZone]

Re: (ibanezplayer)

Quote, originally posted by ibanezplayer »

it won't be caused by getting more air than usual, it'll be caused by loosing air between the maf and the o2 sensor. If there was air entering the system it would lead to a lean mixture.

Not on a turbo charged engine - more air causes the ECM to dump fuel to maintain the A/F ratio. Remember, the code is "rich above idle". Encountered this problem on our 2003 T6 - only kept that car for 6 mos.

Try the smoke test - simple enough - nothing to lose.

 

[JoeLvo]

Re: (ZenZone)

Quote, originally posted by ZenZone »

Try the smoke test - simple enough - nothing to lose.

I hear that's expensive though, is it?

 

[rqc]

Re: (ZenZone)

So if the system thinks it is delivering more air than it really is, it is pouring more fuel in to try to keep up, but the air is not really going into the system, creating a too rich condition. Am I understanding the concept correctly? This would mean that the leak is after the spot where some sensor is measuring it right?

 

[firehawk618]

You are correct. Leak after maf = rich mixture in engine.

 

[Oceans60R]

Re: (firehawk618)

Quote, originally posted by firehawk618 »

You are correct. Leak after maf = rich mixture in engine.

Really just depends on whether its a vacuum leak or boost leak.
Vacuum leak = Lean condition because it allowing unmetered air into the mixture thus raising the the ratio of air to fuel
Boost leak = Rich condition because it is allowing metered air to escape thus lowering the ratio of air to fuel
Many times its very hard to actually read a rich or lean condition because the ECM will adjust the mixture quite rapidly. You will need to look at short term and long term fuel trims to get a better idea of whether the ECU is pulling fuel or adding fuel.

Short Term Fuel Trim= Instantaneous Adjustments
Long Term Fuel Trim= Gradual adjusts over time

Smoke test is easy and cheap. Hook up smoke machine to a hose off back of MAF. Look for smoke.
Cheaper way. Grab a buddy who smokes and have him blow in your hose

 

[xman03]

Re: Check Engine Light (rqc)

Quote, originally posted by rqc »

I have an appointment at the closest dealer in a few days. Our dealer closed and now the closest one is 40 miles away.

That is unfortunate. I used to live in Gainesville, maybe you should find an indy shop that works on Volvo's. I'm sure there are some around town.

 

[rqc]

Re: Check Engine Light (xman03)

Quote, originally posted by xman03 »

That is unfortunate. I used to live in Gainesville, maybe you should find an indy shop that works on Volvo's. I'm sure there are some around town.

There is one that has a good reputation with Volvo and all the right Volvo diagnostic equipment. Since I'm still under my 100,000 mile warranty, hopefully this should be covered by Volvo. But after that, I'm going to try Richard's Imports. This car has hardly needed anything besides regular service though so I don't know how much I'll need a shop. But I am at 93,000. Hopefully it will stay trouble-free.

There was a salesman who worked at the Volvo place in Gainesville for 25+ years, throughout several ownership and name changes. I think its remarkable for someone to stay at one dealership that long.

 

[rqc]

Re: Check Engine Light (rqc)

I meant to update this earlier. It turned out to be a failed seal leading from the turbo to the intake. Another dealer did not seat the connection properly when doing the 90K mile service. This all could have been avoided. It's all fixed now.