Hey everyone. When I was just looking around through the other threads, I read another member's post that had mentioned that the S5's MOP or Metering Oil Pump tends to be unreliable. I didn't want to hijack the thread so I thought I'd ask in a new one. Seeing that I will be starting on an S5 project pretty soon, is MOP something that I should replace right away to avoid possible damage to the engine? If so, recommendations on what type / brand to buy? TIA!

Jason

 

It's electronically controlled and the ECU will drop into a low power mode to limit damage to the engine if it detects failure.

There is no aftermarket replacement part for it, just dealer.

I would just replace the lines from it (New lines will be clear so you can see the oil in them.) and just monitor the oil flow through them and the oil level often.

 

Also, something else to note. More times than not, when the MOP fails it also takes the ECU with it. I am sure someone can explain why this happens, but I have had this happen several times to the S5 that I have and also witnessed it on other people's cars as well. So, if it fails on you and the car goes into "limp mode," you might as well get an ECU when you get the MOP.

 

Ok, thanks for the info. Also, I will soon be building my FC from the ground up using just a rolling shell and will be replacing most of everything. Would you recommend just getting a brand new MOP from the dealer rather than finding a used one somewhere? At least for reliability's sake.

AcidShock: If the MOP taking the ECU out is due to an electrical spike during failure, can this be prevented by adding a fuse in between? I plan on adding a Haltech, or something similar, during my build and I would like to protect the ECU as much as possible.

 

Well, if you get a brand new one from the dealer it is big bucks if I remember correctly. Like really big. If you plan on using a Haltech for engine management I would just premix and ditch the MOP altogether. Search for topics dealing with premixing. If that is not to your liking there are lots of topics dealing with using aftermarket reservoirs and pumps where you would retain the oil injection. You can not remove the MOP completely using the stock ECU unless you get an Rtek upgrade for your ECU. www.pocketlogger.com

 

If you are running a Haltech, you will probably be converting to premix. While the metering oil pump can be run on a Haltech, most don't. Or, get an S4 front cover and use the S4 mechanical pump.

Though you don't need to freak out about metering oil pump failures. They are usually quite reliable.

 

Ok thats good to know, I will keep this in mind and possibly consider moving over to premix. Especially since it will mostly be used for track anyways, it shouldn't be too much of a hassle. Thanks for the info!

 

jason, you can trust aaron cake btw. he's been around a long while and knows his stuff pretty dang well. dont sweat it too much tho.

 

If the car will be a track car operating at high RPM and high load, then you should premix on track days. The stock metering oil pump won't cut it in those conditions.

 

Ok, thats good to know. Ill look into premixing a little more than. Thanks Aaron!