Went out for a brisk drive the the Plus 4 today (just under 1,000 miles on the clock). Sunny but quite cold (the first decent day in Cornwall for a while). Despite the cold weather, opened the bonnet on my return and couldn't believe the heat wave which came out. Bonnet and bonnet stays too hot to touch (despite the louvres) and the "cold" air intake actually a hot air intake since the pipe also really hot. The culprit is obviously the catalyst which, since being "close-coupled" on the GDI is actually inside the engine bay. There is a bit of heat shielding over it but it's clearly not effective. Shudder to think how hot everything will get in high summer. When I get round to it I'll fit some properly designed Duratec manifolds I have (same bolt pattern) and fit a 200 cel metal substrate cat further downstream outside the engine bay and under the wing. Pending that I'll insulate the air intake. Grtfl any thoughts?
I suspect mving the cat out of the engine bay will mean a new map for the computer....the GDI engine is computer managed and the cat is where it is because Ford want it there, nor because MMC put it there.
Perhaps the answer is a "throttle body" type bonnet with a new air intake taking fresh, cold air from the outside.
Peter, 66, 2016 Porsche Boxster S No longer driving Tarka, the 2014 Plus 8...
I recently drove a new Plus 4 around Paris and spent time in traffic jams and driving at low speeds. This was a real test but the car didn't get hot in the way you describe and performed beautifully.
To be on the safe side I would give the dealer a call.
There is not a massive difference in power over the older Plus 4 but it was still a spirited drive - when you could find an open road to put your foot down and the French police were not about!
Thanks for the info on the ports. I shall have to check that. Not too easy to re-route the intake. Think I,ll try reflective insulation on the intake hose and heat wrap on the manifold plus a bit more insulation round the cat. Otherwise, apart from a few blown fuses, car has been excellent.
I don't know how much heat will be put into the air through a warm air supply tube like yours but wrapping it with insulation would help. When I had a 1992 4/4 with 1.6 CVH engine my air supply was similar to yours and was melting underneath so was replaced and insulated. Zircotec coating the manifold will cost you £250+ based on quotes for 4 cylinders. Try exhaust wrap? Air dam underneath the car to draw air out? My current car - 2002 Plus8 - has a polished stainless filter housing and that gets to 40 degrees celcius after a short run with engine at normal temp!
