2001 X5 3.0i - Record for most error codes at once?

[jimmygee]

A shop I use has been struggling with resolving issues of the X5 running rough, hunting horribly while idling and then stalling when idling or when I slow to a stop, as well as times when there is no power in accelleration that seems due to misfires. Just prior I had a history of service light lit due to O2 sensors error after a head gasket blew; they replaced the sensors. 2nd to last time they worked on it we still had other O2 sensor errors posting but also cam shaft sensor error and purge valve sensor codes posted.

They replaced those other sensors to resolve but still had service light lit, which I figured just needed a drive cycle to be completed before it would clear. However, the X5 was still running terribly rough as mentioned above, so I brought it back immediately, and they pursued a vacuum leak as likely cause. No error codes were visible to me using Torque at this time.

The shop looked at the rough running and initially thought it was a vac leak from a crack in the manifold but said they pinpointed the leak with smoke test to be in a vac tube running to the gas tank, which they corrected by replacing the tubing. This time they said it ran normally during their road test afterward but when I drove away, I immediately experienced same problem again; contacted the shop owner and was told to drive it more in order to allow lines to purge. Have only been putting top grade premium in for fuel.

Someone mentioned to me about possible coolant blow-by into a cylinder but coolant levels do not seem to be dropping.

Anyhow, today while driving a couple days into this attempt to drive it more per his request it was running terrible as described and stalled. Then upon restart, a number of warning lights illuminated all at once including ABS, Brake (amber), ASC triangle, EML among others. After restarting again and turning the steering wheel to full travel each way, I've now only got the ASC triangle, Brake (amber) and ABS lit; X5 still running horribly rough as described above though.

I pulled codes with Torque app and got a laundry list (see below).

P0300 - Cylinder Misfire Detected Random Cylinders
P0313 - Misfire Detected With Low Fuel
P1501 - Idle Speed Control Valve Stuck Closed
P1342 - Misfire During Start Cylinder 1
P1346 - Misfire During Start Cylinder 3
P1353 - Misfire Cylinder 6 With Fuel Cut-Off
P1351 - Misfire Cylinder 5 With Fuel Cut-Off
P0037 - HO2S 12 Heater Control Circuit Low
P0051 - HO2S 21 Heater Control Circuit Low
P0444 - Evaporative Emission Control System Purge Control Valve Circuit Open
P1344 - Misfire During Start Cylinder 2
P1349 - Misfire Cylinder 4 With Fuel Cut-Off

These codes include a number of sensors as well as an array of misfire errors, and more. For everything to post errors at once, I'm presuming an electrical or control issue. Anyone have any ideas what this shop has been missing or is now dealing with?

Thanks in advance!

[puddinboo]

did you check the disa valve, if the vaccuum is good or if its getting worn out and the flap inside is sticking?

[jimmygee]

Sorry for not including code descriptions. Here they are as per EngineCodes.com; just gone back and edited the original post as well.

P0300 - Cylinder Misfire Detected Random Cylinders
P0313 - Misfire Detected With Low Fuel
P1501 - Idle Speed Control Valve Stuck Closed
P1342 - Misfire During Start Cylinder 1
P1346 - Misfire During Start Cylinder 3
P1353 - Misfire Cylinder 6 With Fuel Cut-Off
P1351 - Misfire Cylinder 5 With Fuel Cut-Off
P0037 - HO2S 12 Heater Control Circuit Low
P0051 - HO2S 21 Heater Control Circuit Low
P0444 - Evaporative Emission Control System Purge Control Valve Circuit Open
P1344 - Misfire During Start Cylinder 2
P1349 - Misfire Cylinder 4 With Fuel Cut-Off


Will talk to them about the battery and alternator. Any other thoughts, I'm all ears.

Thanks again!

[Dark_stranger]

Originally Posted by trader4

You can drive the car with the DISA valve in any position, operating,
disconnected, etc and it will make very little difference. All it does
is improve the mid-range torque, allegedly and I've never noticed
a difference with it disconnected. If the seal is shot and
it's leaking air, then it could produce a lean condition.

Previously I would have agreed with the above statement, but recently had an issue with rough running, running lean and the engine management light on. I found a split pipe and therefore replaced, expecting the problem to be fixed, but the engine still run rough and the light was still on. Therefore checked the disa value and the flap was missing, checked in manifold and no flap, therefore brought new flap and fitted. No car running fine, no longer running lean and light gone off, and all because I installed the missing flap.

[BimmerM3inGA]

Were you having any of these problems before the head gasket was replaced? Having personally replaced the head gasket on two M54 engines, I can tell you that you have to disconnect and remove A LOT of stuff to do the job. It would be very easy to make a mistake during reassembly.

Is the shop that's having trouble diagnosing the problem the same one who did the HG replacement?

This is how I would approach the problem:

1. Find a different shop.

2. Clear ALL the codes and then see which ones come back.

3. Double check every electrical connector to make sure they are (a) connected and (b) connected to the right thing.

4. The misfire codes are a big clue. They are telling you that the cylinders aren't getting enough fuel. Is the Check Engine light flashing or on steady? You either have a massive vacuum leak, or a problem with the fuel injectors/spark plugs/coils. Solving the misfires will make a BIG difference in the way the engine runs.

I would make sure all of the injectors are fully seated in the fuel rail and that the electrical connections are solid. It's very easy to lose the little metal clips that secure the injectors to the rail, and the ones that secure the electrical connections. If any of those are loose or missing, you will get misfires because the injectors won't be spraying any gas.

It's also very easy to clog the tips of the injectors with crud when handling them after removal. There are fuel injector cleaning services available. It might be smart to find one and have them test and clean the injectors - eliminate that variable.

Lastly, I'd make sure you have sufficient fuel pressure. Maybe you have a problem with the fuel pump or filter? You didn't mention your mileage, but I'd guess it's 100K+

5. Replace all 6 spark plugs with the correct ones for this engine (NGK BKR6EQUP)

6. Do you know if the holes in the block for the head bolts were repaired during the HG job? You have an aluminum block and it's very common for the threads to be damaged if the head warps because of overheating. Job #1 when replacing the HG on an aluminum engine is to install Time-Sert threaded inserts into the block. Otherwise it's likely that you'll never be able to properly torque down the head bolts. I dealt with this exact problem on a 2001 X5 3.0i that I bought after someone else botched the HG replacement. I had to pull the head again and redo it the job. If the head won't tighten down, it will NEVER run right.

I think you need to go back to Square 1 and do a thorough diagnostic on this engine. If all your shop can do is pull codes, I doubt you'll solve it. Somebody is going to have to dig in and really have a look around.

Sorry to be a Debbie Downer, but I'm just trying to save you from wasting time and money on diagnostics that will ultimately be of no help to you.

[jimmygee]

Appreciate all the info and ideas everyone!

So much has happened with the work on this car that I wasn't able to list the entire history. Some of it is indeed pertinent to the assumptions being made so I hope I hadn't led anyone astray by leaving info out for the sake of trying to be concise.

Anyhow, to take a look backward in clarification, the head gasket work went well and I had driven the X5 for some time without any of these rough idling or stalling issues. The shop had dug back into the engine later to address some oil leaks because contrary to my direction, they did not replace all the disturbed gaskets during the head gasket work so I had them dig into it again to address some rather awful leaks that were created. They didn't address the o2 sensor faults during this work either because the shop owner said he could get a good price on some sensors and asked me to wait.

Rather than continuing to wait, I purchased some 'quality' aftermarket sensors myself and then dropped the X5 and parts off with the shop. When I returned to pick up, I was told they had only installed the upstream sensors because the others had incorrect connectors. I found that odd because I had the supplier double check p/n's for my X5 when I ordered. Anyway, I made a mental note of the shop's comment.

...fast forward to today after having the shop tell me my aftermarket sensors must be the cause of the problem...

I bought a full Bosch (OEM) set (2 pre, 2 post) from Pelican which arrived yesterday and so I installed all 4 of them myself today. This was the Eureka moment... when I got into the belly of the beast and started replacing things, it appears that the shop had installed a 'pre' into one of the 'post' spots... because a pre has a short cable with male end (post have the long cable with female end) the shop had to then reroute one of the cables (the incorrect cable) from the engine to it... I suppose that should have been the whiskey tango foxtrot moment for the mechanic but the result was a mix-up of pre and post sensors. The aftermarket o2 sensors I previously purchased were cabled correctly, and I don't have any reason to believe they were malfunctioning or causing this issue. To my knowledge after researching o2 sensors a bit this morning, pres are wide band and posts are narrow band, so the engine instabilities are probably a direct result of the bad o2 sensor data it was getting.

After I replaced all the o2 sensors with the new Bosch and got all the cabling properly sorted out, the engine seems to idle and run properly.

I still have the service engine light lit although no latched codes per my OBDII so I assume that I just need to finish a drive cycle for the light to eventually clear.

Anyone have any thoughts in confirmation or other things to keep in mind? Until then, I'm just monitoring.