AYC pump

[wkd_nas]

Hey guys, my ayc pump has gne in my vr-4. my mates who have evos have said that i'm best leaving it cos when they have repaired ayc it has led to next weakest link (transfer box) failing. I was wondering has anyone had a similar experience regarding the vr-4? Also not sure what the differences are as i have triptronic gearbox.

[Nick Mann]

Huh? That is not something enyone has ever noticed in the VR4 community. I'm not sure I understand how AYC being fixed leads to transfer box failure anyway?

Next question is how do you know the pump has gone? It is often just the pressure switch.

[Scanny]

how do you diagnose an AYC pump Nick? my light is on but it supposedly works in cold weather

[wkd_nas]

had a specialist run a diagnostic on the car which located the fault as AYC pump.
i think what my m8 was trying to say was on his evo the ayc got weaker over time and so when it was repaired the transfer box could not cope. i was just checking with u guys before having the ayc pump repaired on my vr-4 as it is quite costly i've heard.

[Wodjno]

I still concur with Nick. It could still be the switch. A specialist?? wouldn't know about uprated/adjustable switches. Worth giving 1 ago. Availalable for Malc(MBPVR4) here on these forums.

Regarding the Diff giving out after a New Pump fitted ? Can't see how that works ?

Wodj

[Louis]

If its an evo with an active centre diff the ayc pump does both systems, the rear diff and the centre diff. He could have been meaning on this type of set up, if the pressure is low enough to show an ayc warning light, it will not be strong enough to run the centre diff and problems with it will follow, so a new pump is probably better.