Inlet Manifold gets too hot

S3KO4

S3KO4

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As the title says after fixing the oil light issue and few large leaks under the manifold I noticed the inlet manifold gets very hot, as hot as the cam-cover this was never the case with my car in this sort of cold weather... now I feel like it's limiting the power, I can feel it, and the g/s has gone down to 197 from 202!

The charge pipe is much cooler than the inlet so I wouldn't have thought it's do with the 2 SMICS or is it?
 
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Thanks Dave it's a mystery I can not work out! I think I will do the fmic leaving the passenger side on there. just need to get the pipes.
 
Heat soak from the engine will cause the inlet mani to heat up and retain heat... a phenolic gasket will help prevent heat soak but with the smics too a bit of spirited driving later and they will get hot and stay hot... FMIC will also help...

<tuffty/>
 
do you have a polished manifold??? when i had mine polished it got much hotter then it does now its painted, before you could hardly touch it now its just a little warm to the hand
 
Somthing is quite wrong their mate. My charge pipe is normaly bouncing, my inlet is normal cool after a drive, it only gets warm when sat after a run etc but still its not daft temps.
 
s3_kev said:
do you have a polished manifold??? when i had mine polished it got much hotter then it does now its painted, before you could hardly touch it now its just a little warm to the hand
Click to expand...

I have in deed, I was thinking if that was the cause, I did mentioned this to a mechanical engineer, and he said the uneven crackle is there on the cam cover and the inlet manifold to increase surface area, hence dissipate heat more. I scanned it for faults and it says &#8220;intake temp signal too high!&#8221;
 
I remember a while ago someone had/has an S3 that had a similar problem like this. Think he was running lean due to a tired fuel pump, engine heat being transferred to the inlet mani possibly???
 
sandip said:
I remember a while ago someone had/has an S3 that had a similar problem like this. Think he was running lean due to a tired fuel pump, engine heat being transferred to the inlet mani possibly???
Click to expand...

Thanks Sandip for the good tip, could I check using the mean mass block to work out the fuel mixuture?
 
Not sure but i think it's 032 to check fuel trims, a 3bar fpr will make life a little easier for your pump, if you have your old one spare, you could chuck it in and see how it goes
 
The car has been mapped with the 4 bar, if the satndard injectors run 380cc with 3 bar then the 4bar as Dave has mentioned has pushed them to ~430cc by me removing it it will make it run even more lean.
 
I don't want to melt a piston or something, it is def too hot for this weather I will measure the temp next time and check the fuel trims.
 
I'm not a 100% but i think the pump is 3bar and is 'ok' for 4bar, if the pump is a little tired it might not be able to meet 4bar

Time to check fuel trims lol :)
 
S3KO4 said:
Thanks Sandip for the good tip, could I check using the mean mass block to work out the fuel mixuture?
Click to expand...

031 is actual lambda (depending on if your car is wideband or not the number will be meaningfull only if its wideband)
overall fuel trims on block 032 (just look not something to log) and block 001 when looking at lambda adjust % (again wideband vs narrow band cars control differently)

also... if timing is being retarded (high CF on 020) then the engine will run hotter

Phenolic insulator gasket keeps intake manifold temps way way down

contact me for more info if of interest
 
These Phenolic insulator gaskets sound interesting....is there any data to support their cooling claims?

I can feel my wallet twitching again.....
 
Thanks Bill for the idea of the Phenolic insulator gaskets, I will first have to look into those blocks if nothing is found in the core then I might have to splash out on it. :(
 
badger5 said:
031 is actual lambda (depending on if your car is wideband or not the number will be meaningfull only if its wideband)
overall fuel trims on block 032 (just look not something to log) and block 001 when looking at lambda adjust % (again wideband vs narrow band cars control differently)

also... if timing is being retarded (high CF on 020) then the engine will run hotter

Phenolic insulator gasket keeps intake manifold temps way way down

contact me for more info if of interest
Click to expand...

Good thread on SeatCupra.net I was wondering how much would you charge just for the Phenolic insulator by itself?
 
Isn't there a thread in the stickys which say that someone did back to back testing and one of these gaskets did not make them any power at all?
 
SiGainey said:
Isn't there a thread in the stickys which say that someone did back to back testing and one of these gaskets did not make them any power at all?
Click to expand...

They don't actually make power, just helps keep what you already have... a bit like a decent FMIC etc... a heatsoaked inlet manifold can undo some of the cooling effort made by an intercooler and will help it shed off any heat it does soak up more quickly...

<tuffty/>
 
I've always wondered this... Given that the air is in the inlet manifold for what must be a fraction of a second, how much does it heat up?

I think that the gaskets are a good idea and would put one on my car as they are not going to make it worse, but as for whether they give a significant benefit, I'm not convinced but I'm open to some facts on this :)
 
SiGainey said:
Isn't there a thread in the stickys which say that someone did back to back testing and one of these gaskets did not make them any power at all?
Click to expand...

those selling them as power gainers are talking BS...
its an insulator gasket, gives you nothing, but preserves what you have got against the inevitable heat soak the AIT sensor will see given its location in the inlet oven... Erm I mean manifold.
 
SiGainey said:
I've always wondered this... Given that the air is in the inlet manifold for what must be a fraction of a second, how much does it heat up?

I think that the gaskets are a good idea and would put one on my car as they are not going to make it worse, but as for whether they give a significant benefit, I'm not convinced but I'm open to some facts on this :)
Click to expand...

its not that its in there for not long, but the ecu's air temp sensor does live there and it thinks it blindingly hot!
 
The sensors presumably insulated from the manifold though (it is after all made from plastic), and from what i've seen, the sensor element itself is further isolated from the sensor body by being more or less suspended by two thin wires into the airstream.

You might see a slight skew, but its not going to be reading 90c rather than 20...
 
******. I read a sticky on here that said it gave no power increase whatsoever, backed up by what was said above.
 
it wont give power like above, but rather stops the heat to transfer from the head back to the mani, and I would have thought a gain of 10mm in four manifolds should increase a bit more air available to use! or maybe that's too insignificant.
 
Yes but its not unusual for an heatsoaked engine to drop 10 bhp so they are trying to say that the 10 bhp is theres, but its not its your own before the heatsoak...lol
plus a car on a dyno is gonna suffer more heat soak than been on the road, so with a decent intercooler the difference wont be massive, but every little helps
 
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aragorn said:
The sensors presumably insulated from the manifold though (it is after all made from plastic), and from what i've seen, the sensor element itself is further isolated from the sensor body by being more or less suspended by two thin wires into the airstream.

You might see a slight skew, but its not going to be reading 90c rather than 20...
Click to expand...



...and if the sensor sits inside an oven, it will still see heat wont it. Radiated heat!!!
its radiated heat NOT conducted heat the sensors seeing.
It will drop as soon as it see's some cooler airflow from the throttle body opening, but quickly revert to the internal ambient
 
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