X5, E53 3.0i missfire problem

[selkent1]

Hi all

Please dont stick me with spears as i know this has been covered many times in other places and there is very rarely one answer that applies to all, but i didnt think a new thread would hurt.

Just got myself a new E53, 2003 model, 3 litre petrol, and love it but it came to me with a (apparent) missfire. So i put a cheapy OBD reader on it and it said something along the lines of "missfire on cylinder 2 with low fuel" and it was also giving me an error for the cam sensor.

The car starts mainly ok and seems to run a bit lumpy and after about 30 seconds or so, it then gets really lumpy. It does drive and sometimes seems like it wants to stall, but hasnt yet. The lumpyness is also accompanied by a strange kind of muted whining noise that seems to be coming from the right hand side of the engine (as you look at the car from the front).

Before i did anything i checked the history of the car and it has around 130K on the clock with a main dealer history up to around 6k ago, and in the mass of paperwork i had i could not find any evidence of a problem like this effecting the car before so i started with the basics. I moved the coil from cylinder 2 to another cylinder, and cleared and re read the codes! No change. So i stuck in a new set a Bosch coils and plugs, no change. Still doing the same thing, still getting the same error messages. Then im thinking dodgy injectors. So i put in a new injector to cylinder 2, and still missfireing, although now the OBD was saying that the missfire was cylinder 4. So new injectors later and still its there and now its back to cylinder 2 again.

Scratching my head a put on a new cam sensor just in case it could be that as i read somewere that this could be a possibility, and no change. So i looked at the induction. I put on a new MAF and no change there either. So thinking that maybe ive got some kind of leak i put a new set of breather hoses and new intake manifold gasket, and it kind of improved a little, for a while, but then went right back to how it was before. I have sprayed around the boots and pipes etc, when idling to try and detect any leaks and nothing. So i am starting to think dreaded head gasket however i mentioned this to a friend at work and he said everything was starting to point towards that but for the strange whining noise.

Ive got no was of performing a smoke trest for leaks in the induction and ive got no way of performing a compresion test to see of the head gasket is toast!

Anyone got any ideas?

Hope all are well

[dworthy]

Spraying flammables around the motor is rather dodgy, so stay away from that. Even if it did idle up, it would only find gross leaks, and not small leaks.

You have a vacuum leak, so find a shop that can do a smoke test and make sure the intake is fully sealed. An easy test will confirm this, unplug the MAF and see if the car runs better.

[selkent1]

Hi and thanks for your help. Will find a garage that will do this although not that easy here. I didi do your thing regarding the MAF though. I unplugged it to see if it would run better and i did this iver several instances to compare results and all were mixed. The first time i unplugged it, it instantly ran better, not perfect but a lot better. The second time i unplugged it, the uneven running seemed to get worse and the last time i unplugged it, the engine cut out altogethe! Make of that what you will!

Phil

[selkent1]

Another update.

I plan on spending a day removing all parts of the intake, induction and vacum system to inspect and see what is going on. I discovered this morning after a jump start that my battery was goosed, along with a broken battery terminal. So replaced one and am waiting on the battery, which should be here tommorow. I also replaced (yes i know its unlikely to be that) the DISA valve but as suspected, no change. I started the car this morning after about a week of standing and the rough running and weird noise from the engine was unchanged but this time there was something else. The only thing i can compare it to is the sound that metal makes when it starts to warm up only a lot louder. It happened abouit four or five times and then nit again after that. No other weird symptoms followed it. Nothing out of the exhaust, the rough running didnt seem to change and then it didnt happen again.

Anyone else got any additional thoughts on this matter?

I am very limited for time so havent had the chanve to investigate this properly yet apart from throwing the parts at it that i have so far.

Just to recap, i have fiitted,

New Coils (Bosch)
New Plugs (bosch)
New MAF
New air filter
New Inlet manifoild gasket
New breather hoses
New DISA valve
New Air con compresor (yeah unrelated, but i thought id throw it in there!)

Again, like i said before i have had more than one person suggest that it is head gasket or something head/valve related, and yes everything suggests that except for the weird muted whining noise that comes from under the bonnet and seems to change according to the revs. I was just going to throw caution to the wind and buy a recon head and throw that on with a new gasket but many have said dont as it could be a waste, and even though i have done plenty of heads in the past, i have never done a bm one and have never dealt with a timing chain. So hopefully its not that.

Again, looking for anyone who has had similar issues and has somehow resolved them, Maybe it could help me.

Hope all are well

Phil

[dworthy]

So before you toss a head on it, a couple of things should be done first.
1) Compression test
2) Leak down test
3) Borescope
4) Coolant pressure test
5) Check coolant for exhaust gasses.

Yes these can take a couple of hours to complete, but you will know in the end if they are sealed properly.

Just like getting a smoke test for the intake, you do that to find any small/gross leaks and then you go back again to ensure is it all properly sealed.

[bmwdirtracer]

May I just give you a few observations?

First, when you unplug the MAF for diagnostic purposes, the engine needs to be off, not on. Unplug it, then start it. It should stumble briefly, then, if your misfires are related to intake leaks only, they should go away.

Secondly, and most important: You need to DIAGNOSE first, THEN throw parts. Throwing parts when you don't know why just complicates the issues. For instance, if that new MAF was not a VDO/Siemens unit, you may have fitted a terrible Chinese part. Bosch isn't the best sparkplug for your engine, by the way. That would be NGK BKR6 EQUP, but never mind....

A smoke test is really the only way to find intake leaks. Some potential leak spots are the oil return hose to the dipstick tube, the CCV valve, etc, and they won't respond to flammable gasses at all. When you go in, taking the manifold off and such, you're very likely to cause new leaks in other places.

Test and diagnose first. Can you read codes from the computers, write them down word for word, then clear the codes?

[selkent1]

Thanks for replying.

Regarding the MAF, no it waws a BMW original, yes i was tempted to get a cheapie from ebay but no, that came from stephen james so unless they have sold me a dead unit, i dont see a problem with that. Regarding the plugs, yes i do hear that various plugs seem to do better for various makes and models of cars but can it really make that much of a difference. One thing i do remember that could be worth mentioning seeing that you mention the oil return is that when i removed the intake manifold, that oil return pipe has a plastic connector on it that allows it to clip onto the bottom of the CCV valve (which i also replaced), and this was loose enough to just slide off of the connector and the area underneath was covered in oil. Cleaned up and now fixed i initially thought that could have had something to do with it but after rectifing the issue, nothing changed.

Regarding errors, i only ever get two. I cant remember the codes but one is something along the lines of "missfire cylinder 2 with low fuel" and the other is for the camshaft position sensor (which i forgot to mention i also replaced, and yes it came from BM).

After replacing the cam sensor and upon noticing that i was still getting the error i returned the part to BMW and they explained that the problem could be something else however, they exchanged the unit and the problem never went as i still get that code now.

Interestingly after replacing the breather hoses, i did read a code that said the missifre was now in cylinder 4, then i cleared and re read and then it said it was cylinder 2, 4 and 5. Then after a restart it went back to just 2 and its been like that ever since. No warning lights are on the dash either.

Hope this gives a little insight.

Phil

[MarcoZandrini]

As for the cam shaft position sensor, check to see if oil has wicked up the cable and reached the engine computer (DME in BMWspeak).

[selkent1]

OK, just another update. But followed advice regarding the MAF sensor. I unplugged it then started the car and even though that weird noise was still there, the miss seemed to almost dissappear. Tiny bit of lumpyness there but virtually unoticable. So it looks like its a leak problem after all.

I am unable to do a smoke test, so does anyone have any other ideas regarding procedure or process for inspection?

Phil

[selkent1]

As for the cam shaft position sensor, check to see if oil has wicked up the cable and reached the engine computer (DME in BMWspeak).

Have checked that and the wire and casing is oil free

[dworthy]

A shop will have to do a smoke test as the machine tends to be rather expensive for a individual to purchase.

[selkent1]

Well,

I followed the advice here and disposed of the bosch plugs and fitted the NGKs that were specified, and fitted my new battery and behold, even though the weird wining noise is still there, the missfire and massive lumpiness and wanting to stall has almost gone, and that's with the MAF plugged in. So there is obviously some kind of leak there which might explain the noise, but how can the plugs make such a difference. I have had 5 different bmws before this and have always stuck to bosch plugs!

[bmwdirtracer]

Did you replace the correct cam sensor? There are 2 - one for the intake cam, one for the exhaust cam.

The whining noise COULD be the same issue as what's left of your lumpy idle: an intake leak that causes a whistle in the CCV or elsewhere. The crankcase vent valve is generally replaced as a kit, with 4 associated hoses/plastic pipes, all of which tend to break when you touch them, or by themselves, over time. One of these is that oil return hose, which often conceals a break under its braided cover. The CCV is infamous for causing a whistle when it goes bad, although you might have a bad tensioner or idler pulley, or even a bad alternator, any of which can cause whining. The way to diagnose these is with a (carefully used) mechanic's stethoscope, which is very inexpensive.

[selkent1]

Thanks for responding. We're is the location of the second sensor please and what type will I need?

Many thanks

[selkent1]

Hi all,

After finally finding the location of the second sensor and a visit to the local spares, that is now replaced and any evidence of a missfire seems history. Although while looking underneath i spotted the large hose that comes from the bottom of the CVV valve and even though i put a jubiliee clip on it to hold it to the clip that holds it in place, it still seems to be leaking. Not sure if that could be the cause of any lumpiness, which is still there ever so slightly, but nothing i would say is a missfire.

Anyone else had any problems regarding that large bottom hose?

Phil

[bmwdirtracer]

The oil return hose rots, inside the sheath. You can't see it, because of the sheath. Now, I'm not saying that your oil return hose is rotted and broken, but I will tell you that I have seen at least fifty of them that were.

Your best bet is to get a smoke test with a pro smoke machine, but if you want to throw parts without testing, throw the CCV with 4 associated hoses/pipes. It's pretty cheap, and a well known failure part and maintenance-replacement item.

https://www.fcpeuro.com/products/bmw...-11617533400kt

I know, you're in England, but these are the parts you need.

[selkent1]

Hi all,

after mcuh investigation, and replacing the oil return hose, only to find out that it hadnt rotted. Then i discovered the the outer chamber of the disptick tube was completely blocked, to the extent that you couldnt even get compressed air down it, so i replaced that and....no change.

However, i dont know why but i removed all the plugs and coils again just to check for oil ingress into the plug chambers and while i was there give a nice squirt of carb cleaner as i went and something weird happened. You remember from my earlier post that one of the most common messages i keep getting from the OBD is a missfire on cylinder 2, and upon squirting the carb cleaner into cylinder 2, it would eject through the spark plug hole of cylinder 3. The same thing would happened if i squirted it into the the plug hole of cylinder 3m it would then eject up through the hole of cylinder 2! That certainly does not seem right. And for whatever reason, my coolant is now full of sludge. Creamy sludge. Im not loosing any, and there is nothing in the oil, but i think its all steering towards head gasket, as there is notihing else i can possible replace on the induction and ignition side that could cause the problem.

I have the gasket now and the locking kit and although i have done plenty of heads over the years, i have never done one of these six pots.

Anyone know of a step by step guide, almost like a checklist, of how to do this? Including some instructions on how to use these locking kits. I undersnad were the crank locking pin goes, and what the small jig for mounting the front sprokets is for but that about it.

Given the absence of a haynes manual for these cars, and this timeslot i have for doing the job doesnt give me enough time to get a bently manual delivered, anyone got any tips or downloads or anything that could help???

Regards all
Phil

[bmwdirtracer]

Do NOT just change the head gasket, it is a waste of time and money.

The head gasket on this engine goes BECAUSE the head warped, when the engine overheated. Worse still, when the head warps on this engine, it rips the threads out of the aluminum (aluminium for you) engine block.

To fix this issue, you would need to
(1) send the head to a machine shop for milling flat. The timing cover needs to be reduced by the same amount. .009" is the stated maximum, but you can purchase a thicker head gasket and go .012"
(2) Buy a fixture specifically for the M54 engine rethreading, and insert Timeserts (thread replacements far superior to a helicoil) in ALL the cylinder bolt holes of the block.
(3) Don't forget that head bolts are stretch-to-yield, and not reusable)

Seriously, I have done this job a few times, and it's just not worth the effort. Here in the US, I can buy a used M54 engine, complete, for ~$500, and swap it in ~20 hours, including transfer of parts. With 4 wheel drive, add at least 8 hours.

All the head and block work will cost you far more time and money.

[selkent1]

Hi and thanks for your response.

I understand that overheating is a major cause of head gasket failiure, however, My car is a one owner from new vehicle, prior to myself, and i have a full history of the vehicle, down to every lightbulb etc, I contacted the previous owner and they explained that the car has never overheated or suffered any kind of cooling related problems. It was explained to me by the previous owner that they went away and left the car standing for a couple of months. Upon returning they noticed that it was slightly lumpy, and so the plugs and coils were changed after it was found that a coild had gone out. This was done at a main dealer. However after that the problem seemed to get slowly worse to what it is now. The owner explained to me that they were planning on selling the car soon anyway so never bothered with a fix. Yes it is one of those cars that had EVERYTHING done at the main dealer.

Reading your comments did worry me3 however i am of the understanding that head gaskets can just fail.


Phil

[bmwdirtracer]

Before you begin disassembly, do these 2 tests:

(1) a leak-down test. This will tell you if you have compression leaking from one or more cylinders that are supposed to be completely closed. Basically, you turn the crankshaft until each cylinder is closed, and pressurize the cylinder with at least 160 psi of compressed air, and see where any leaks come from: intake, exhaust, crankcase, or cross-cylinder.

(2) Before removing the head, undo and retorque each head bolt, one at a time. If any bolt won't achieve correct torque, you're going to need to timesert the headbolt holes in the block.

And if you do remove the head, you need to check it for straightness, and the block too. A perfect straight edge and a set of feeler gauges will do; check in multiple orientations , especially across the walls between cylinders.

[selkent1]

Hi again peeps. Hope all are well.

Just a little update. I wasnt able to perform a leak down or smoke test as recommended by you all here however, i decided to replace the head gasket and i am glad i did because upon removing the head, i didnt find any evidence that the head gasket had gone but instead i found this...






As you will see, the crack doesnt seem to interfere with any area concearned with the conbustion apparatus, but is has kind of "blown out" under the coolant chamber. The only thing i could think of is that maybe at some point there has been a coolant leak up front somewere and maybe someone has put cold coolant into a hot engine and caused the fracture, other than that, i have no idea how this could have happened, and in all the heads i have changed over the years i have never seen a failiure like this.

So i set about obtaining a replacement head, and oils, filters etc, and yes i did get a new set of head bolts. After i took the old head off i made sure that i could torque the bolts into the block just to make sure that there had been no warping of the old head thus, pulling at the threads. All was well.

The replacement head and cams...

[selkent1]

And the replacement head with the cams installed and head back on the block






- - - Updated - - -

I had to take the Vanos gears from the old head and use them on this one as the replacement never came with them, and timing them up required a bit of concentration but in all honesty i found it easier than messing around with a timing belt, although i will say to anyone that you NEED to get a timing kit as without it, you will have a mare of a time getting it timed.

https://hosting.photobucket.com/imag...027_170228.mp4

[selkent1]

Sorry about the new posts people as normally i would just have one long post but my browser is doing silly things so at the moment im having to do it like this.

So i got the timing bang on and the head any everything is back and there are no leaks and it drives superb. And yes i did rebuild the vanos with new seals etc, while it was off. But i still have a problem. Before i replaced the head, when starting from cold the engine would run very lumpy, and it would be lumpy to the point of almost stalling, and it would also make what sounded like a loud kind of metallic click every now and again. This would last for a minute or so and then the revs would buld a bit and it would level itself out a bit, but obviously it would drive and run very lumpy. That lumpiness is gone now and it drives like never before however, upon starting it still makes that same metallic noise albeit, for only around 10 or 20 seconds and it is a bit lumpy when it does this, but then it goes away and all is normal.

Obviously something is causing this but im stuffed if i know what it could be. All condistions on the dash are fine with no warning lights. Oil and coolant are new with no leaks, all hoses are connected where they were before!!!!

So kind of scratching my head at the moment, I Have pretty much replaced everything i can think of now but cant get rid of whatever it is causing that problem.

The car has had

Replacement Cylinder Head
Head Gasket
MAF sensor
CAM position sensors (both of them)
Coils
Plugs (NGK)
All breather hoses and a CVV valve
Repalcement air con compressor (not replated i know)

The only thing i never replaced was the thermostat which looked new and i tested it in hot water and it good.

Any ideas peeps

Phil

[bmwdirtracer]

I'd check the idler and tensioner pulleys with a stethoscope, and I'd surely replace the water pump and thermostat.....because really, that's just a given if you're replacing a cracked cylinder head. I'd have probably just replaced the two pulleys too, during that work.

And of course, a smoke test of the intake/ccv system, to find your intake leak. You've spent a bunch of money and kept everything organized and correct and clean, might as well finish up.

[selkent1]

Well havent got that much of an update.

Apart from the cold starting issue. When its been left for about 30 seconds or so the engine just purrs! but upon startup its a real pig, seems to be missing like before and backfiring through the intake manifold, again, just like before, although not as bad.

I have visually checked everything i can think if, making sure that every hose in connected, every electrical connector is connected, and plugs and coils are all good. I have replaced, like i mentioned before, both cam sensors, and the MAF, and still i cannot get rid of this problem. Once its run for a but the problem dissappears and it runs smoothly, with only the occasional slight "wobble" when idling, but upon acceleration its perfect.

I am at a loss. I have come across others who have had this problem and the cure seems to vary from car to car. I have tested all the "cures" on mine and nothing seems to make any difference. Many have said it could be a fuel issue, but how would that explain the back firing through the intake manifiold?

Phil