Not your average SES P0171, P0174 error code...

[Whoopitupinmo]

How did your indie know it was the MTV?

I know you say they used a smoker. Is there a way to do this without taking it back to the dealer. Don't have a lot of equipment at our office/shop but would be interested to see if this is my problem, rather than valve gasket cover.

[adnoid]

Originally Posted by Whoopitupinmo

How did your indie know it was the MTV?

I know you say they used a smoker. Is there a way to do this without taking it back to the dealer. Don't have a lot of equipment at our office/shop but would be interested to see if this is my problem, rather than valve gasket cover.

They did use a smoker, and saw the smoke being drawn into the control unit. But I also heard a whistling noise when I started the engine, and it was really loud when first started and subsided as the car warmed. What I did is, when I noticed the noise, I opened the hood and took a picture with my phone of where it seemed to be coming from & emailed it to them to give them a place to start.

That said, this particular part looks very simple to remove - it's out in the open and uses an O ring seal, so if it's OK it should just go back in if you are careful removing it, worst case I guess would be a new O ring.

[Whoopitupinmo]

Thanks - probably not my issue then, do not hear any whistling or load noises under the hood. This is just baffling, performance seems a little hesitant at warm up, maybe first 2 minutes after I start the car, put in gear then go it does seems to hesitate for a minute or 2, then all is fine.

[adnoid]

Originally Posted by Whoopitupinmo

Thanks - probably not my issue then, do not hear any whistling or load noises under the hood. This is just baffling, performance seems a little hesitant at warm up, maybe first 2 minutes after I start the car, put in gear then go it does seems to hesitate for a minute or 2, then all is fine.

That's kind of what I had. It was the last start before I took it in again when I heard the whistle - not much before then.

Here are the necropsy photos - you can see that the actuating shaft appears to be hollow. Doesn't look to me like it could be a huge leak, but I've now got 100 miles (as I stated above) and I have no codes stored whatsoever.

[Puddlejumper]

I know I saw on here a DIY where somebody took it apart and caulked it.

[adnoid]

Just a follow up - 2 tanks of gas and a week of daily driving and no more codes. Gas mileage back to around 20, and drives great.

[X5Tanya]

Originally Posted by mdadrass

Hello all,

Let me begin by thanking all of those that contribute to this fine forum as the information posted here is worth it's weight in gold.

My Problem...SES P0171, P0174 codes coming up on my 2001 4.4i (4/2001 prod) X5 with 59K miles. Here are my issues other than the codes:

1. Low gas mileage (3-4mpg worse)

2. The car stalled twice a while back at very low idle but not since.

3. lower power at full throttle

I checked the 2 vent hoses on the top connected to the oil separator for cracks but could not find any although they really felt pretty mushy and beat up.

After searching the threads extensively I've come up with these solutions:


1. Check/Replace Vent hoses that connect to the oil separator

2. Replace Fuel Filter

3. Clean/Replace Mass Air Sensor

I'm looking to sell the car soon so I really just want the SES light off and done with.

Am I missing anything here or any other suggestions?

Thanks in advance!

I am currently going through the exact same problems you have!!.. I have smoked the intake system for vac leaks, and none found. I am putting on an MAF sensor on monday, I'll keep you posted.

T

[X5Tanya]

Well, I put a new MAF sensor on monday and so far no SES light on! It used to come back on the next day after resetting the light. I also replaced the seal after MAF to the air tube and the seal from the air tube to the throttle actuator- now things are really snug in those places where before even though the clamps were tight it still was not snug. I also replaced the hose that goes between the throttle actuator to the purge valve- just seemed to be the next weakest link for an air leak Hopefully this will help you guys in trying to find a possible air leak after ther MAF sensor.

[tbc111]

Originally Posted by adnoid

Funny - I just started to get these codes as well. 2002 3.0 with 202,000+ miles.

Last week I had a brief stumble in the morning, followed by the SES light on the drive to work. Other than the stumble the car drove just fine, with one significant difference - much BETTER gas mileage! I usually get around 19, I suddenly was getting 23+. When I was able to read the codes I got:

P0171 (System too lean, Bank 1)
P0174 (System too lean, Bank 2)
P0300 (Random/multiple misfire detected)
P1347 (Misfire cylinder #3 with fuel cutoff)
P1348 (Misfire cylinder #4 during start)
P1350 (Misfire cylinder #5 during start)

I noted them, cleared them & left the reader connected. The next day the SES returned with all the above codes and these:

P0302 (Cylinder #2 misfire)
P1083 (Fuel control mixture lean, Bank 1)
P1085 (Fuel control mixture lean, Bank 2)
P1342 (Misfire cylinder #1 during start)

I took it to my indie repair shop (good guys) and they replaced the pre-cat O2 sensors and the intake boot which had a crack in it. I could discern no difference in behavior of the car before or after the repair, but right after I picked it up my fuel consumption was back where I thought it should be. Then the next day I got the SES again with just P0171 and P0174, along with the reduced fuel consumption, albeit only up to about 21 MPG. I reset the codes again, and although the light has not come on again I can see P0171 and P0174 are pending.

What's interesting is that this began to happen immediately after I filled up at a station I don't usually go to, but I was low and running an unplanned errand. It was a Miristar and the pump said the fuel could contain up to 10% Ethanol - has anyone else experienced any such connection?

Still, the car runs great - fires right up without hesitation, not lacking power, smooth, and if not for the lights/codes and the increased mileage I'd have no idea anything was going on!

Hi adnoid! How's your X doing nowadays? I'm been having the same problem for the past couple of weeks. That SES light keeps coming back after gassing up.

My X's been going in and out of the shop for resetting and clearing fault readings. This of course after having replaced O2 sensors and checking for leaks (so far none found). It's still in the shop and more checks are being done inlcuding cleaning of injectors.

I'd really like to hear the latest on you guys who have come up with some solutions to this problem.

[adnoid]

Originally Posted by tbc111

Hi adnoid! How's your X doing nowadays? I'm been having the same problem for the past couple of weeks. That SES light keeps coming back after gassing up.

My X's been going in and out of the shop for resetting and clearing fault readings. This of course after having replaced O2 sensors and checking for leaks (so far none found). It's still in the shop and more checks are being done inlcuding cleaning of injectors.

I'd really like to hear the latest on you guys who have come up with some solutions to this problem.

Check out posts #32 and #34 - since that repair no problems and running like a champ. Except now I have a sunroof problem, totally unrelated...sigh.