robster330ci Posted November 3, 2014 Report Share Posted November 3, 2014 Hi everyone, I have been having a problem with my 2003 330ci for the last few weeks. it started occasionally misfiring at idle, would be fine when going along. After about 30 minutes of this the engine check light came on. I done some research, found that the MAF sensor commonly causes this, and I disconnected it. As soon as I disconnected it the car ran almost like normal again, no misfires etc. I ordered a new MAF from eBay, and fitted it yesterday. At first it seemed to be fixed, but after 30 minutes of running the car the problem returned. This morning it got so bad that I'm sure the engine was running on 5 cylinders. I have disconnected the new MAF now and its fine. My question is, is there another component that works with the MAF that I need to look at? Or have I just got unlucky and been supplied with a duff MAF? Any help much appreciated. Thanks Rob Link to comment Share on other sites More sharing options...
daveo132 Posted November 3, 2014 Report Share Posted November 3, 2014 Personally I think you're wasting your time with a MAF from eBay. I wouldn't trust any of them. I'm about to get a new one from here http://www.maf-shop.com/index.php?currency=GBP&language=en&cat=c8_BMW.html&cPath=8, all genuine items direct from Germany and a lot cheaper than anything else I've found in the UK, about half the price than anything from BMW. I couldn't say if it's your MAF at fault. I'm only changing mine as I've tried my best to rule everthing else out. Hope that helps. Cannockwolf, CharlE46 and robster330ci 3 Link to comment Share on other sites More sharing options...
CharlE46 Posted November 3, 2014 Report Share Posted November 3, 2014 Rob it may well be a duff maf, was it one of the cheap ones on there or a genuine Bosch? either way I'd be returning it to the seller. Thanks for the link Dave, I may need a new maf soon (if cleaning it doesn't work) daveo132 and robster330ci 2 Link to comment Share on other sites More sharing options...
pete_h Posted November 3, 2014 Report Share Posted November 3, 2014 Hi everyone, I have been having a problem with my 2003 330ci for the last few weeks. it started occasionally misfiring at idle, would be fine when going along. After about 30 minutes of this the engine check light came on. I done some research, found that the MAF sensor commonly causes this, and I disconnected it. As soon as I disconnected it the car ran almost like normal again, no misfires etc. I ordered a new MAF from eBay, and fitted it yesterday. At first it seemed to be fixed, but after 30 minutes of running the car the problem returned. This morning it got so bad that I'm sure the engine was running on 5 cylinders. I have disconnected the new MAF now and its fine. My question is, is there another component that works with the MAF that I need to look at? Or have I just got unlucky and been supplied with a duff MAF? Any help much appreciated. Thanks Rob You need to get it plugged in and the codes read, or you may well end up replacing parts that dont need replacing. If you fancy a bit of DIY you can buy a VAGCOM cable for under £10 and with a little soldering it will work on the BM - this is the most cost effective way to get a working cable. Link to comment Share on other sites More sharing options...
robster330ci Posted November 3, 2014 Author Report Share Posted November 3, 2014 Thanks for the responses! Dave - Thanks, this looks good. I will order from there if I get another one. charlie46 - It was a cheap £35 from eBay. I may try cleaning the original with some switch cleaner, I didn't try this before because it looks spotless! pete - I have a code reader, it claimed something like 'Lambda fault in cylinder #' and it was logged many times with all 6 cylinders. I will send it back anyway, I was thinking " I will get a cheap one, its only a sensor, if it fails again in a year ill buy another" I at least expected the damn thing to work. CharlE46 1 Link to comment Share on other sites More sharing options...
robster330ci Posted November 3, 2014 Author Report Share Posted November 3, 2014 I have attached some pictures of fault codes i read this evening. Appreciate any help! Link to comment Share on other sites More sharing options...
pete_h Posted November 3, 2014 Report Share Posted November 3, 2014 Check your intake boot for any splits robster330ci 1 Link to comment Share on other sites More sharing options...
robster330ci Posted November 4, 2014 Author Report Share Posted November 4, 2014 Hi, thanks for the suggestion. I have just checked all the rubbers, and no splits. Link to comment Share on other sites More sharing options...
the_driller Posted November 4, 2014 Report Share Posted November 4, 2014 £35 quid maf sensor more chance of curing aids than that thing working. Sent from my GT-I9500 using Tapatalk 2 Link to comment Share on other sites More sharing options...
robster330ci Posted November 24, 2014 Author Report Share Posted November 24, 2014 Ok, bit of an update. I got a new genuine MAF sensor, still the same problem. Done a bit of investigation this evening and checked all the intake boots, no splits - all looks fine. What i also did is remove the DISA valve and i instantly noticed it is broken, right at the base so it cannot open and close. I will get a new DISA, or a rebuild kit, but can any of you clever people tell me whether the broken DISA will cause the lumpy running issues when the MAF is connected? As previously mentioned the car runs almost perfectly without the (NEW) MAF sensor connected. Cheers Link to comment Share on other sites More sharing options...
the_driller Posted November 24, 2014 Report Share Posted November 24, 2014 Nah im afraid the disa wont affect the running of the car.. you can go ahead and unplug it if you like. Sent from my GT-I9500 using Tapatalk 2 Link to comment Share on other sites More sharing options...
robster330ci Posted November 26, 2014 Author Report Share Posted November 26, 2014 Just to put a conclusion to this thread. I fitted a new DISA this evening and it has fixed the problem. Plugged everything in properly including the MAF and car runs perfect! It may have been a vacuum leak due to the flap being completely broken on the old DISA. Cheers all for all the suggestions. L4nky808, Chimp Choker and marc l 3 Link to comment Share on other sites More sharing options...
