Piston Slap: SHO Me The Intercooler Condensation!

Zac writes:

Hi Sajeev,

I have a confession to make. I may have lied on my last TrueDelta survey. I reported ‘No Repairs,’ but, while technically true, I have been struggling with a problem for a few months now. My 2011 Ford Taurus SHO has been my long distance cruiser for 99,000 miles now, often times pulling an eight-foot trailer full of bikes and gear to track days all over the Southeast. I installed an Airraid cold air intake, Corsa Cat-Back exhaust, and Stage 3 tune from Livernois Motorsports at 17,000 miles, and the car has run fantastic until about 4,000 miles ago.

Accelerating at low RPM, part throttle, high gear, the car hesitates, “shudders,” or misfires until the transmission decides to downshift or I decide to mash the gas pedal. Midrange to high RPM, mid to full throttle, the car still takes off like a raped ape, but if you drive it like a grandma it just doesn’t do well at all. Obviously, the first thing I did was return the engine tune back to stock. All that did was make the car slower overall. It still had the same acceleration issues at low rpm, part throttle.

I was able to pull a code from the ECU: P0306 – “Cylinder 6 Misfire Detected.” Perfect! I replaced the number 6 ignition coil, and the code went away, but it still didn’t fix my problem. I’ve cleaned both MAP sensors, and the IAC. I checked and replaced all 6 spark plugs (they actually looked pretty good — a little bit of material worn away from the side electrode, but the color was perfect). I finally gave up and dropped the car off at the dealer for a $130 diagnostic.

The mechanic complained that he couldn’t get any codes off of it, and that I need to put the stock airbox back on before he can do any more troubleshooting. The car has had this cold air intake for 80k miles! I clean and oil it every 5k miles with the oil change. I don’t have the airbox for it. Something is worn out on my 100k mile car and the dealer can’t (won’t) tell me what it is, and I can’t figure it out. Should I replace the rest of the coils (at $50 per coil)? Replace the sensors? Oxygen Sensors? Water in the intercooler (how would I check that)? Transmission issue?

Sajeev answers:

How DARE YOU lie to TTAC-alum Michael Karesh? But I discount any vehicle’s repair woes after such modifications. Not that Livernois Motorsports sells junky tunes, but it’s no longer a factory-engineered vehicle. And having the dealer diagnose the problem is similarly unpleasant for all parties involved: the world revolves around unmodified cars.

That’s not hate, all my rides are tuned to your SHO’s extent. So I’m happy to assist. There are multiple problems within this engine code: none apply because your WOT (wide open throttle) runs are flawless!

There must be an Ecoboost specific (i.e something to do with turbocharging, direct injection or intercooling) concern — Googling netted the intercooler condensation problem. The best explanation came from a TDI forum, leading to this factory PDF. Ford’s fix is an intercooler restrictor plate, with downsides frustrating enough to make one reconsider natural aspiration. Another fix outside of a remote-mounted catch can or in-line purge-valve-something-or-other is not likely.

But seriously, ask Livernois Motorsports for their advice, as anyone with experience in HVAC freeze ups knows the harsh reality: Thermodyamics is a bitch.

Bonus! A Piston Slap Nugget of Wisdom:

Son, you shoulda got a Coyote-swapped Crown Vic as a tow pig.

Or maybe a Lightning-swapped Crown Vic. It’ll haul your load!

Or, of course, hashtag LSX-FTW hashtag Panther Love: