Overheating Tuscan engine

Overheating Tuscan engine

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Discussion

JamesSim

Original Poster:

497 posts

259 months

Thursday 15th September 2016
quotequote all
Hi Folks,
My standard 4.0l engine is overheating and running really lumpy, both connections on the air box had snapped off.
It's just been serviced and when cold it's fine and smooth but as soon as the engine warms up and your sitting in traffic etc the heat is unbearable from the passenger side of the engine.
The air box connections were modified in the service but when I removed the engine cover, the front pipe had disconnected again, I haven't removed the air box cover to check the other yet.
Could this be the only reason or could it be HT leads etc?

Many thanks

James

Englishman

2,215 posts

209 months

Thursday 15th September 2016
quotequote all
S6 manifolds on the N/S of the engine do get really hot, but the CAT's get even hotter, to the point of red and then white hot if combustion starts in them due to incorrect setup!

There are three pipes to the airbox, the large one for oil fumes, the small one at the front for fuel regulator and the small one at the back for barometric pressure.

Was it serviced by a top expert? If so I'd call them, otherwise get it to someone who knows what they are doing to sort out before it gets expensive.




Edited by Englishman on Friday 16th September 11:55

JamesSim

Original Poster:

497 posts

259 months

Thursday 15th September 2016
quotequote all
Thanks David,

Andy_mr2sc

1,223 posts

175 months

Thursday 15th September 2016
quotequote all
Vacuum advance on a speed 6 with no distributor? I must have a different speed 6 to everyone else as my front small vacuum pipe goes to the fuel pressure regulator. Best a call a Tvr top expert to see how my car has been plumbed in incorrectly.

Edited by Andy_mr2sc on Thursday 15th September 22:18

m4tti

5,426 posts

154 months

Friday 16th September 2016
quotequote all
As above there is no vacuum advance. There's a fuel pressure regulator.. And the oil tank vents to the airbox.

When you say it's over heating what temps are you actually seeing.

JamesSim

Original Poster:

497 posts

259 months

Friday 16th September 2016
quotequote all
Hi Matt,
I think it might be the cats, my son has ordered the 3 pin adaptor and has the software to investigate a little further,
My car hasn't been off Jersey for 8 years now and cats just do t get to operating speeds over here.
My dash readout isn't operating properly as it freezes if you try and interrogate it, it will display alarms such as low battery, oil pressure etc on startup.

Kind regards

James

Andy_mr2sc

1,223 posts

175 months

Friday 16th September 2016
quotequote all
James did it run ok before the service? Obviously you cant see the temperature but is it overheating as in boiling up or just getting really hot around the manifolds/cats?

JamesSim

Original Poster:

497 posts

259 months

Friday 16th September 2016
quotequote all
Hi Andy,
Yes it was running rough before the service, and the heat is all around the cats and manifold, so much so that the paint is showing fine cracks above it on the bonnet.

Andy_mr2sc

1,223 posts

175 months

Friday 16th September 2016
quotequote all
That is common to find. I have stick on heat shield on my bonnet and scuttle panel and even now I still see a little bit of heat discolouration. I de catted mine which helped a lot with the heat but I guess where you are it could be tricky finding a friendly mot centre?
As you say plugging it in and checking the ecu data would be the first job. A misfire as I am sure you are aware could be from many different sources. If it runs ok from cold the coil, leads or plugs could be breaking down from the heat but this could also be a faulty temperature sensor telling the ecu the engine is still cold when it has warmed up so the engine will be given too much fuel.
I really would consider getting your dash looked at too. These can be repaired. Seeing vital info like oil pressure/temperature and water temperature early could save you huge expense from damaged components if you had for example an oil or water pump failure.

mk1fan

10,507 posts

224 months

Friday 16th September 2016
quotequote all
Ceramic coating the manifolds and CATs will relieve the heat soak into the passenger side. It will move the heat down the exhaust but at least it is moved to 'exposed' pipework.

Sounds like the service / tune needs a review. Did the mechanic have the diagnosis tools?

Englishman

2,215 posts

209 months

Friday 16th September 2016
quotequote all
Andy_mr2sc said:
Vacuum advance on a speed 6 with no distributor? I must have a different speed 6 to everyone else as my front small vacuum pipe goes to the fuel pressure regulator.
Quite correct and what I meant at the time, must be getting old!

JamesSim

Original Poster:

497 posts

259 months

Friday 16th September 2016
quotequote all
Thanks once again Andy,
De-cat is the route I will be going down, in Jersey there is no legal requirement for Cats, they don't work here due to the too low speeds, modern cars are having to be continually reset as they often go into limp home mode.
I spoke with my service guys this morning, they were originally factory trained and have the diagnostic equipment, they have also said to bring it back in as they will give it a thorough examination and test drive.
My dash pod is a salvage replacement since the original went pop, however the original will be sent back for an overhaul, even though the original only had water temp, oil temp and pressure readouts due to it being a very early car.

Kind regards,

James

Andy_mr2sc

1,223 posts

175 months

Friday 16th September 2016
quotequote all
Englishman said:
Andy_mr2sc said:
Vacuum advance on a speed 6 with no distributor? I must have a different speed 6 to everyone else as my front small vacuum pipe goes to the fuel pressure regulator.
Quite correct and what I meant at the time, must be getting old!
No worries and excuse my sarcasm. I blame the bottle of merlot personally.


James it sounds like your guys know their stuff and should find the fault. Typically on here as with most forums you ask ten people and get ten different answers depending on peoples personal events with their own car. As mentioned the manifold area does get hot and there are ways of easing this. I'm guessing because of where you live you do a lot of relatively slow driving and don't get to open it up much and get some air flowing through the car?

Edited by Andy_mr2sc on Friday 16th September 14:59

mk1fan

10,507 posts

224 months

Friday 16th September 2016
quotequote all
I bought a set of Clive F decat pipes and had them ceramic coated in black. I didn't have the pipes polished as it seemed pointless to do when they were being coated.

Doing the manifolds as well will also help preserve the engine mount.

JamesSim

Original Poster:

497 posts

259 months

Friday 16th September 2016
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Thanks for all your help

andypg

80 posts

162 months

Sunday 18th September 2016
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Clive f decats are the way to go. They are the best quality items on the market imho. No more hot gear knob, cabin cooler aswell. Temperature doesn't go over 92 degrees even in traffic.

crypto

229 posts

240 months

Tuesday 11th October 2016
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The S6 engine gets extremely hot. A while ago I made an infrared picture after coming home from a ride.
http://thumbsnap.com/gZBzonlg (this was in a Cerbera)

The cats were around 300 degrees Celsius and easily go up to 400. You certainly will get the temps down when you remove them (and you will immediately smell it on the exhaust gases).
I know some have a fan installed blowing towards the manifolds to get the heat out ...

Here is the entire thread
http://www.pistonheads.com/gassing/topic.asp?t=130...

Peter