[Joe90]

Erratic idling 1.4 BCA engine

I hope one of you good people can help me here. The engine on my daughters 2007 Beetle seized solid so I've replaced it with a good BCA engine from a Golf. My problem is the car starts fine but after a short time the idle becomes really erratic and the EPC light comes on. If I rev it right up it settles down, the light goes out and will tick over fine until I next rev it when it repeats itself.

I'm tearing my hair out with this one, I've looked for air leaks etc but can't find anything obvious. Can anybody help me out of my misery?

 

[Joe90]

A common problem; is the PCV valves fail and this causes, a air leak (requiring a new pcv or a whole new valve cover). Have you scanned the car for trouble codes?

Here is a thread; about the PCV failure issues, that are common with the 2.5L engine:

http://newbeetle.org/forums/2-5-liter-gas/65633-re-2-5l-pcv-valve-failure-solutions-dorman.html

Thanks for your help Billymade. I've not scanned it for faults yet as I've been looking at the obvious coils etc but I'll do that tomorrow. would it correct itself temporally as the car drives really well and the tick over issue comes and goes with regularity?