matrox02 0 Report post Posted March 23, 2019 Hey all, I have a 2001 e39 525i that I recently acquired with a few things wrong, I recently had to replace the intake elbow, the CCV, rebuilt the VANOS( one that seems to be leaking out of the housing now, frustratingly) , replaced the plugs and coils, replaced the DISA seal and rebuilt it ( the plunger holds vacuum ) and now she starts and seems to drive just fine, HOWEVER, today I popped her into sport mode ( tip-tronic ) and noticed that she doesn't feel as fast as I would have thought she should be and after 4 krpm she seems to surge in power ? its not a heavy cut in and out kind of power more so like a soft boost in power while revving that seems to come and go? ive been scratching my head on what it could be and the only thing I can think of is possibly the fuel pump is slowly on its way out? or the Fuel pressure regulator? she idles dead smooth and starts easily every morning, and unfortunately I haven't been able to monitor short term and long term fuel trims to see if something is up, is there something else that I could check? Quote Share this post Link to post Share on other sites
Eagle 1680 Report post Posted March 23, 2019 Sound like you have not scanned it yet or reset adaptions? Cleaned the MAF sensor? Quote Share this post Link to post Share on other sites
matrox02 0 Report post Posted March 23, 2019 13 minutes ago, Eagle said: Sound like you have not scanned it yet or reset adaptions? Cleaned the MAF sensor? Ive scanned it, I havnt reset any adaptations,Not sure how I can reset adaptations? Ill have to look it up, and not touched the MAF, No codes other wise, I only have a bluetooth ews2.7 ODB scanner and its a "fake" one so i know some apps dont work with it Quote Share this post Link to post Share on other sites
Eagle 1680 Report post Posted March 23, 2019 Ok. I usually give the MAF a clean for good measure when doing work like this. Checking the fuel system is easy enough on these with the schrader although i'll bet the fuel filter is very old so probably check that with the regulator at the same time before the pressure. 1 Quote Share this post Link to post Share on other sites
matrox02 0 Report post Posted March 23, 2019 a MAF clean is probably good practice , Ill give that a go, im waiting on a friend to lend me his injection tester kit, Ill likley need to replace the fuel filter as you say! Quote Share this post Link to post Share on other sites
matrox02 0 Report post Posted March 27, 2019 Just got done with checking my fuel pressure, 50 psi while on idle and 45 psi not running, that is within tollerance I think? Quote Share this post Link to post Share on other sites
Eagle 1680 Report post Posted March 27, 2019 Not sure what BMW spec but it sounds reasonable. Key on and off a few times may have brought it up to 50. Did you check the pressure when being revved, like 2-3k. Did you disconnect the fpr via vacuum hose in engine bay and check that. Quote Share this post Link to post Share on other sites
matrox02 0 Report post Posted March 27, 2019 7 minutes ago, Eagle said: Not sure what BMW spec but it sounds reasonable. Key on and off a few times may have brought it up to 50. Did you check the pressure when being revved, like 2-3k. Did you disconnect the fpr via vacuum hose in engine bay and check that. no, only idle and off testing, didnt disconnect the FPR either, Ill give that a go though when i have time Quote Share this post Link to post Share on other sites
matrox02 0 Report post Posted April 8, 2019 Tested Fuel pressure the other day, Solid all the way through the RPM range, This morning however, i fired her up and she was misfiring REALLY badly, scanned her immediately and got p1350 and p1342 so a cylinder 1 and 5 misfire, which.. shouldn't be happening as Ive Literally just replaced the coils, plugs and rocker cover gasket + other stuff , after about a minute she started to idle ok , still no check engine light, but she also is idling louder than usual now... Either im missing something or I still have a vacuum leak??? Quote Share this post Link to post Share on other sites
matrox02 0 Report post Posted April 9, 2019 To update it, ive been watching lots of youtube vids, and found it could POTENTIALLY be water intrusion from heavy rain, since my bmw lives on the road ill assume it was that as it hasnt done it since and hasnt really rained since, ill keep an eye on it, though im still a bit paranoid that not all the power is there that should be , Ill try new Cam position sensors some time soon though Quote Share this post Link to post Share on other sites
