jeffbebe 1560 Report post Posted November 6, 2013 The one-way valve to the exhaust from the secondary air pump is blocked/knackered and will make the SAP die a slow death so I ordered a replacement from Gavin at Euroitalia. Unfortunately, when he finally got it ex-Germany the cost was 3 times the list price he'd originally quoted. Not his fault at all but it's a lot more than I expected. Since I'm planning to remove the second set of cats because they're ruined anyway, I wondered whether I might be better just deleting the SAP altogether. It's easy enough to unplug but wondering if there's anything else I need to do? Should I put a pvc cap over the hose from the broken valve? Will the ECU need recoding if it's unplugged? Or should I just spend the extra and fix it even though it'll only be warming the small pre-cats? Quote Share this post Link to post Share on other sites
M3_Power 636 Report post Posted November 7, 2013 (edited) My understanding is it is almost impossible to remove without some sort of fault code showing up about it. The system is very cleverly tied in with O2s, voltages, MAF and the whole DME system. I know some of the folks on the E46 M3 forum have looked into the coding of this and reckons that it can be written out with quite a bit of effort ... but it'd take quite a bit of doing and unless you are a programmer you are sh*t out of luck I am afraid. Also the Evolve SAP delete is apparently just a deletion of reporting the fault ... i.e. the fault is still there, it just doesn't report it, so no CEL lights. Edited November 7, 2013 by M3_Power Quote Share this post Link to post Share on other sites
jeffbebe 1560 Report post Posted November 7, 2013 (edited) Ah... That's annoying. So what about the threads saying Euro spec software doesn't include SAP in the engine check? Is that just hiding the fault? EDIT: I am right in thinking that the SAP does nothing other than heat up the cats on cold starts for emissions reasons, right? Edited November 7, 2013 by jeffbebe Quote Share this post Link to post Share on other sites
jeffbebe 1560 Report post Posted November 7, 2013 (edited) BTW - I unplugged it previously and didn't get a CEL light. Have subsequently scanned fault codes and there was no historical fault for the SAP. If it had thrown a fault that would have shown up even though I plugged the SAP back in, wouldn't it? Hoping my ECU isn't checking for it... EDIT: I'm deleting it today so we'll see what happens. I won't remove it completely until I'm sure there are no faults showing and everything's running as it should. Edited November 7, 2013 by jeffbebe Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted November 7, 2013 (edited) I've done E46's without problems. Put a blanking plate (steel) between the valve and pipe to seal off the exhaust. Fit a ball bearing in the vacuum hose to block it and unplug the SAP. Leave everything else hooked up and it all looks original. Edited November 7, 2013 by *Glenn* 1 Quote Share this post Link to post Share on other sites
jeffbebe 1560 Report post Posted November 7, 2013 Thanks Glenn, I was hoping you'd chime in!! Exactly what I wanted to hear. Cheers Quote Share this post Link to post Share on other sites
jeffbebe 1560 Report post Posted November 8, 2013 Done it. No faults and SAP completely removed. Car's running great and it seems to have fixed some rough idling. Car still seems to run some sort of noisy (not as noisy as it was) operation for a minute or so at start up even though the pump's disconnected. Can anyone (Glenn!) tell me why that is? Quote Share this post Link to post Share on other sites
Phil-540i 166 Report post Posted November 8, 2013 Good move - now at least it'll be breathing nice clean pure air................... Quote Share this post Link to post Share on other sites