Need help with tracing cause for pinging?

[rusteee 52]

Hi guys

I have an issue with bad pinging all of a sudden, in my 2002 530i E39 233,000kms. Hoping someone can help with a bit of troubleshooting or a way to locate the problem, if possible.

It happens around town when the cars hot, if I put my foot down slightly or going up hills, really cant stand the sound. 95% of my driving is highway as you can tell by the km's, but through town I drive in "sports" or in a lower gear to keep the revs up to reduce it. There is no flat spots of power that I can notice, and the car drives smoothly. I run Mobil (97.5) octane, I have changed spark plugs (BKR6EQUP), New viscous coupling, and no fault codes are present in the system.

It has had cold idle issues ever since having the cooling system replaced, which they never managed to sort, wether that's related or not I don't know (vacuum leak?). I was hoping to take the car on a road trip around the north island as of Wednesday and hoping I could atleast try reduce/eliminate the issue, as I know what sort of damage this can do.

Is there any way to check, diagnose what could be causing this? Or can a live data diagnosis by a BM workshop locate the issue? I have the car booked in at a BM workshop but not till the 14th, and not for this issue, but I'll add it to the list if I can't get it sorted before then

Cheers

Edited January 6, 2013 by rusteee

[Allanw 1071]

I guess a vacuum leak could cause it, but I would have thought it would log a code of some kind before it got lean enough to cause preignition that the car can't adjust for, like fuel trims or O2 sensor issues. If it was running hot, it could do it too, but usually the cause is the Map-control thermnostat going open circuit and that should log a code too.

I've heard of Vaons problems causing cold running issues (common as!) but I don't know if it usually causes pre-ignition.

Probably best to have someone (who knows what they are doing!) look at real-time data while it's doing it and see if anything stands out.

[rusteee 52]

I had the VANOS done a while ago, which is still a bit rattly, don't think the spacer was sized properly, but work great none the less. The car doesn't run hot the cooling system is working perfect, and the car cruises great (just done another 400kms this weekend), it just makes me cringe around town when I hear that dreaded noise.

Yeah I want to take it in ASAP and have it checked properly but I don't know where, I suppose i'd have to book it in anyways and may take a few days. I've tried the simple things like what I had listed but no. I'm hoping that this sort of problem can be traced to something as it seems like it can have a lot of causes and can be hard to trace.

[Allanw 1071]

Ok I assume the vanos seals were done too... Are you sure it's pinking, not a heat sheild vibration or some kind of valve train rattle?

[rusteee 52]

Yeah I got the whole kit done. I hope it was done properly, my car was the guinea pig car. I am almost 100% sure its pinging, theres no ticking or tapping noises like valves or anything like that, just when you put your foot down and load the engine a bit its like a metallic 'Pinking' noise. I notice a lot of bimmers do it when taking off at traffic lights and what not, same sort of thing, sounds like shyt. Of course nobody else notices it, but now I've heard it I keep listening out for it

[hybrid 1043]

You need to get a scanner on it and look at the live data from the MAF, O2 sensors (pre and post cat) and additive and multiplicative adaption values to see what the car is doing first.

This needs to be done under different load conditions.

It will then give the right place to look for you problem.

The ECU has a very good knock detection so it will just simply shut the engine into engine limp mode if the car is running either too lean. The engine will then not rev over 1500 RPM.

[NZ BMW 368]

Yeah I got the whole kit done. I hope it was done properly, my car was the guinea pig car. I am almost 100% sure its pinging, theres no ticking or tapping noises like valves or anything like that, just when you put your foot down and load the engine a bit its like a metallic 'Pinking' noise. I notice a lot of bimmers do it when taking off at traffic lights and what not, same sort of thing, sounds like shyt. Of course nobody else notices it, but now I've heard it I keep listening out for it

Timing chain noise caused by lower oil pressure when the car is sitting at idle? Just looking at the number of km's.

[rusteee 52]

Cheers for that. Yeah I have a scanner with all the live data etc onto my tablet, but I don't quite know what to look for, so need someone who knows what they are doing. I am almost certain it is pinging as all the signs are there, except for flat spots in power, the engine runs well, cruises well but when giving it a bit of load through town in traffic you can hear it. I don't think its chain noise, but possible at that mileage. Wouldn't chain noise happen throughout the revs though?

[BM WORLD 1283]

double and tripple check for vac leaks , maybe a air pipe knocked off under the manifold when doing coolant hoses etc,

the breather pipes from the rocker cover to the pcv perrish , also all other rubber pipes that get splits in them when they get old etc

[rusteee 52]

double and tripple check for vac leaks , maybe a air pipe knocked off under the manifold when doing coolant hoses etc,

the breather pipes from the rocker cover to the pcv perrish , also all other rubber pipes that get splits in them when they get old etc

Thanks for the help guys, really appreciate it. Yeah I suspect it could be possible vacuum leak as I doubt anything has been replaced in the way of hoses etc. I think I might just take it easy, most of the trip will be highway anyway and seems all good cruising. Not enough time now to start ripping it apart and have a look, so will leave it till I take it on the 14th, and hopefully have it sorted amongst other things =), will keep posted though in case someone may find them selves with the same issue

[rusteee 52]

Have had the car in for a few bits and pieces. Unfortunately the pinging could not be traced to anything, maybe im just being too nit picky with noises? They confirmed that there are no vacuum leaks, VANOS is functioning correctly, sensors etc are all working correctly, they could not get the car to ping and overall the car is running very well. They were very thorough and spent a bit of time looking over the vehicle. All the work carried out was excellent, very happy with how its come up. So will just ignore the noise and see how it goes =)