Member
I have a 99 328i sedan and I replaced the upper and lower hoses along with the sensor and the expansion tank, and I've still got some sort or coolant consumption or leak. I've pressure tested it and havent found anything. I dont think there is a leak and it's not my head gasket. My secondary airpump is however throwing a code, any ideas?
Member
If you drop pressure on the coolant pressure leak test however no visible leaks then perform a compression / leakdown cylinder test.
Last edited by RobertDenali; 11-07-2018 at 08:07 AM.
Member
The cooling system in the E46 demands that it be properly bled. Go to E46Fanatics and check out a sticky in the cooling system that was written by Mango. You likely have air in the cooling system.
Member
The cap on the expansion tank is prone to leaks. Easy replacement to try.. Get an OEM one, though.
Member
You might want tø google or research secondary air pump overhaul or repair on an audi. I've owned audis since 2000 model year and have seen lots of secondary air pump (and those damned combi valve failures...even had a couple of those!) failures online but fortunate not to have one.Originally Posted by Minimule77
Member
I replaced the cap when I replaced everything else, I bled it too, you think the consumption could be due to air in the system? I also plan on replacing the air pump.
Member
Yes, air in the system can present as a leak as the air is forced out of the system, though you may want to accomplish a compression leak down test.
Generally, with a SAP failure, it was a failing SAP valve that allowed exhaust gasses into the pump bearings. If you have a failed pump, it is best to replace the valve.
Sent from my iPhone using Tapatalk
Posting Permissions
Reply With Quote
Bookmarks