My 2004 Disco II has been pushing a P1415 code, apparently for at least a couple years. I have changed out the SAI pump (with a used but supposedly functioning one), the solenoid and the purge valve so far and I'm still getting the code, except every once in a great while I'll hear the SAI pump run and actually NOT get a SES light. I have a new set of vacuum tubes on order but they have not arrived yet. While waiting for those, I dug through the stack of maintenance records my father-in-law gave me when I got the car from him and found a receipt for some work done a little over two years ago. In the Customer line it has his name and "CODES P1415" and in the Description line it states:
"Vehicle has lost ground to the starter relay. When we put a jumper relay in the starter relay position and turn the key on, the vehicle will start. We had a locksmith check the
security and found no issues. We have signal out of the ignition switch. I put a body control module in the vehicle with no results."
This sounds more like a starting/lockout situation rather than a SAI system issue (in spite of the 1415 code at the top), and my father-in-law doesn't remember what all was going on with the car at the time, but could a faulty ground be triggering the P1415 code if it's getting to the ECU? Or could there be an O2 sensor issue telling the ECU the SAI system isn't getting the air to the cat when it really is?

If those are unlikely, I'll see what happens when I put the new vacuum lines in. After that will be the control valve--I believe 1415 is the passenger side code--and then the air line to the manifold. By then I'll have pretty much swapped out everything except the vacuum reservoir...

I think this dead horse has been kicked into oblivion, but one more time--is the air pump supposed to sound like an oversized hair dryer or is that a sign of impending failure? I'd hate to think I wasted $75 bucks on that thing but I can do it 9 more times before I'll have paid for a new one from AB!

 

Most of the time the noise is because the rubber mounting brackets have broken due to age and the pump is resting on the metal bracket, transmitting all the vibration in to the car. If that is the case try suspending the motor off the metal with zip ties, you may need to actually ditch the bracket to get enough clearance. It quieted mine right down.

 

I ditched the rubber that constantly dies in TX for 3 bolts. Yes I can hear the pump more vs before, but it only runs for maybe 1.5min. Then silence! Or you can get 3 new rubber bushings. 1412/1415 are usually vacuum line or nipple related. Could also be a bad solenoid mounted over by the purge control valve.

 

I'll look into the bushings, although the ones that came on the replacement pump looked new. I already replaced both the solenoid and purge valve with OEM parts, although there's always the possibility of one of them being bad right out of the box. Hopefully the new vacuum lines will fix it. Really don't want to have to go through the butt-pain with the NC DMV again this year to get a waiver for the emissions inspection... Otherwise the Disco seems to be in pretty good shape other than a few quirks that I'll get to as time permits--definitely road-worthy though.

 

How do the little rubber 90 elbows look? I've seen those crack and leak. The other main area of a vacuum leak with SAI is the rubber connection at the intake. I've seen people secure them with zip ties, or use other ways to connect it vs the OEM setup. The main big hose which runs off the pump can also crumble into bits or crack since it's so close to the exhaust manifold on the passenger side. If you cut off the special end at the pump and leave say 3-4inches of a straight section you can lube up a 3/4 fuel line or 3/4 heater hose and slide it over the straight section of hard SAI pipe to the pump. That way you keep the special BMW style SAI pump fitting, then run enough hose so it can connect to the 3/4 metal pip when runs behind the engine to the other side. The OEM hose can be purchased for 100.00 or more vs 6.00 of 3/4 hose.

The SAI system isn't that bad BMW used that kind of system on several of it's cars of the same time period. It does not like vacuum leaks or you will end up with silly 1412/1415 faults often. I just prefer non SAI setups due to more space under the hood.

 

I'll take another look at those elbows in a week or so when I get back from taking my son to college. I believe those come with the new vacuum lines I have on order so if they're damaged, hopefully I'll swap them all out in the process. I didn't see any obvious cracks or brittleness in the main line coming off the pump when I replaced it, but that was a while ago and I wasn't really sure what I was looking at yet. I'll take a good look at that too, and I like your idea of using the 3/4" tubing to splice between the special connectors. 6 bucks vs 100+ works for me! I'll probably be furloughed in October since airline travel is still in the crapper, so I'm all about saving money if I can. I'll report back after I get a chance to take another look at things & get those new vacuum lines installed. Thanks for your help!

 

No problem

 

Replaced the whole vacuum line system with a harness from Rovers North and still getting the P1415 all by its lonesome. I inspected the new harness before installing and all looked good. While I had the vacuum lines off, I took the air supply hose off the passenger side (I believe that's bank 2?) air control valve and checked for any kind of residue in the supply side of the valve--clean as a whistle and no obvious cracks/leaks/etc in the rubber connector hose between the metal tube and the control valve. Unfortunately, I do not have a vacuum tester to test the valve itself. Other than that I'm pretty well stumped. I've already replaced the air pump, the solenoid, the vacuum control valve, and now the vacuum lines. The only thing besides the air control valve(s) and air supply tubes that I haven't replaced is the vacuum reservoir, but wouldn't that cause P codes for both banks?

Is there anything on the electronics/sensor side of things that could trigger the P1415 by itself? Bad ECU? Bad sensor in the cat (what/where is this sensor)? Missing a ground somewhere? I'm starting to grasp at straws... I have a coolant leak somewhere but I hesitate to start going down that (probably expensive) road if I can't even get the Disco to pass the emissions test so I can drive it in this state. Unless that coolant leak could somehow be causing the P1415...

 

So the best way to troubleshoot it is to make sure each component is working.

To test the manifold valves, get a short piece of vacuum hose the right size and connect it to the intake manifold fitting on one end and the exhaust manifold valve on the other end, pull the SAI hoses. Turn on the engine and you should hear the engine exhaust. Do them one at a time and you can see if either exhaust valve is bad.

Next is the vacuum solenoid valve near the IAC valve. You will need to jump it with 12v and make sure you can blow through it (use the hose). No flow off, flow on. You will likely hear it click also.

Seems like you can hear your blower, so that is not the issue as long as it actually outputs air. The fan could be damaged, so jump the relay in the fuse box and hold your hand over the output and make sure you feel airflow.

The ECU has to give the engine a rich mixture on cold start so it will run, but it commands SAI flow to lean out the mixture and get the cats up to temperature faster. So it can tell if there is no flow from SAI because the o2 sensor will read rich. As long as your oxygen sensors work well, and the rest of it works ok, you should not get a code.

Good luck!

 

Thanks, Extinct. I'll get on that next week when I have some time. So, if an O2 sensor is the problem I would assume I would get more than just the P1415 code, but if everything else checks OK that might be another thing to look at.