White Dust From Exhaust

[Madwhip]

Race fuel can make an exhaust look white.

[_Velocity_]

Yeah still not sure what it is. It went away after my initial post so I put it down to carbon build up. Was driving it the other day and as the revs hit about 4k the car surged then backfired and the same white dust popped out of the exhaust. I thought a baffle in a muffler or the cat had dislodged and blocked the exhaust since the car was shaking on idle and wouldn't make any reasonable amount of power without labouring.

Went back to the dealership and left it there for a couple of days and they said for a car with hotdogs fitted to the exhaust (was like that when I bought it from Ford) it drives like normal (it's under warranty so maybe they are dodging me to avoid some serious repairs). They checked the ignition, plugs and coils for misfire but found nothing and no error codes. I'm not sure if it's heat related and that is why it didn't repeat itself at Ford but I'm kind of disappointed with their response. I said I would be happy to take one of their mechanics for a drive and show them exactly what is wrong but they weren't interested.

Picking it up tomorrow and will be seeking a second opinion elsewhere.

[_Velocity_]

I mamaged to get a mechanic at Ford to hop in the car with me so I could demonstrate what was wrong. Initially he said it seemed the car was running lean under load but after more than a week at Ford they have diagnosed the problem as a failing boost solenoid due to overboost from the car. Their Service Rep said to me over the phone that they think the overboost is being caused by the F6 Intercooler and CAI installed on the car. After reading the forum thread on overboost I am thinking that the cat must be different (or gutted).

If replacing the boost solenoid doesnt fix the problem their next plan of attack will be replacing the F6 components with stock XR6T parts. To me it sounds like something a proper tune will fix but I doubt the dealership will pay out of their own pocket to send the car off to one of the site's advertisers. I might have to cut my loses and pay for it myself. Is there anything else that the overboost could have damaged after the solenoid went cactus?

[Stazza_Brendan]

Heaps of people run f6 parts without trouble. CAI and direct replacement cooler shouldn't worry the stock tune.

[Panda Eyes]

my wallet has dust come out when I open it.... and the occasional moth.