Chris Evans

So I’ve a problem with my ep91 glanza, it idles fine however it bogs down (revs die down then pick back up to idle speed). It’s had new plugs, new leads new rotor arm and distributor cap, fuel filter is new, new fuel pump, I’m beginning to run out of ideas now. It’s got td04 with a piggy back ecu. Once I’ve got it driving properly I will get it mapped. Does anyone have any ideas what could be causing this?