Skoda Fabia MK2 exhaust manifold red glow....??? is that normal

[alenyohannan]

please help for my query, my fabia 3 cylinder engine exhaust manifold red glowing, is that normal or what? 

[mrgf]

I know manifolds get hot but I have never seen one glow in normal road use... I would expect someone racing a car to get it that hot (Or even quit prior to ruining things) But not on the road.

[Phil-E]

Under what driving conditions?

 

You'd have to have been racing round a racetrack non stop for that to happen.

[sepulchrave]

10 hours ago, alenyohannan said:

please help for my query, my fabia 3 cylinder engine exhaust manifold red glowing, is that normal or what? 

 

Of course it's normal, exhaust gases are extremely hot, they're the product of an explosion which reaches thousands of degrees momentarily. How else would it get that hot, a dwarf with an oxy-acetylene torch hiding under the bonnet?

[sepulchrave]

I'm not sure what I said to get the downvote, whether it was the reassurance of normality or the dwarf joke?

[alenyohannan]

7 hours ago, Phil-E said:

Under what driving conditions?

 

You'd have to have been racing round a racetrack non stop for that to happen.

thanks bro... 🙏🏼 for responding.... Actually its happening when i start the car after ten minutes i can see its red glowing from exhaust manifold header.... Only who has a skoda fabia mk2 petrol version owner can only help me wheather is it normal or any issue....🤔🤔🤔

[alenyohannan]

7 hours ago, sepulchrave said:

 

Of course it's normal, exhaust gases are extremely hot, they're the product of an explosion which reaches thousands of degrees momentarily. How else would it get that hot, a dwarf with an oxy-acetylene torch hiding under the bonnet?

🙏🏼Thanks for response bro.... Actually I m not that much expert to analyse it... Yesterday, when i cold start my car. I heard cat sound under the car so i open the bonnet...🤔 At that time i saw this manifold header glowing under manifold guard bracket...😱 I don't know is that normal or not..🙄 i think anyone having the same car (skoda fabia mk2 petrol 3 cylinder engine) can solve my query about this... 

[Phil866]

I have a 1.2 htp 12 valve and I have never seen the manifold glow red hot, or even change colour (on this or any other standard road car). It sounds like the valve or ignition timing is out allowing still burning gasses (or an incompletely burned mixture) into the exhaust system rather than the cooler post ignition gasses of a correctly timed engine. So unless you are using jet fuel it should not be that hot. 

[Phil-E]

That's definitely not normal.

 

As I said before the only way you should, under normal circumstances, be able to get it glowing would be under very hard driving for a prolonged time. But 10 minutes after a cold start is not normal at all.

 

I'd suggest the engine needs looking at as the fueling is obviously off somehow causing very high exhaust gas temperatures.

[sepulchrave]

Jet fuel is basically diesel and burns much cooler.

However, I have seen exhaust manifolding glowing red hot many times, particularly on modern cars which run extra hot from cold start to get the cat lit as quickly as possible.

If the engine were running badly then that might be suspicious, but a red hot manifold on a running stationary car in and of itself is not symptomatic of a fault.

[Breezy_Pete]

I'll go out and observe ours shortly, maybe even point an IR thermometer at it while it runs for 10 or 15 mins. 

[Breezy_Pete]

So, I warmed up the engine (1.2 12-valve 2005, code AZQ) whilst stationary, from an ambient of 0°C over about 12 or 13 minutes.

Held revs higher (around 2000) for some periods when I got a bit impatient after 7 or 8 mins.  Coolant temp showed 90 after about  ten minutes. 

Highest temperature seen on IR thermometer was 270°C, pointing at manifold next to oxygen sensor and at cat body just below heatshield, same in both locations. Reached that temperature within about 3 mins of start up.

 

Unfortunately, when I look at the IR thermometer, it has a upper range maximum of 270! So that wasn't the best tool for the job. 

 

No sign of glowing red anywhere under the heatshield though.

I'll try reading some temps with VCDS next time I start it up, I think there are some measuring blocks that can estimate the manicat temp via the resistance of the oxygen sensor heater.

 

 

 

 

 

 

 

 

 

 

[Breezy_Pete]

Couldn't resist getting some better info before dark and before the engine cooled right down again. 

Log attached.

Max cat temp around 650C, which isn't far from red hot according to google.  That was with revs held up at about 2k, cat temp drops back by about 50-75° to 585-ish when engine is left to idle.

Coolant temperature showed 90 on gauge when the VCDS temp was only 60 which is a bigger fudge-factor than expected. Never got higher than 84 in VCDS, even after a further 11 mins of running, which makes me wonder if a new sensor is due. 

 

 

Cat temp log Jan 2021.CSV

Edited 24 January, 2021 by Wino

[alenyohannan]

2 hours ago, Wino said:

Couldn't resist getting some better info before dark and before the engine cooled right down again. 

Log attached.

Max cat temp around 650C, which isn't far from red hot according to google.  That was with revs held up at about 2k, cat temp drops back by about 50-75° to 585-ish when engine is left to idle.

Coolant temperature showed 90 on gauge when the VCDS temp was only 60 which is a bigger fudge-factor than expected. Never got higher than 84 in VCDS, even after a further 11 mins of running, which makes me wonder if a new sensor is due. 

 

 

Cat temp log Jan 2021.CSV 53.04 kB · 0 downloads

Thankyou so much for your response bro 👍🏻.... If there is any fuel mixing or fuel injection or any other issue on engine due to this atleast we can read it through VCDS... Right? But when i connect VCDS there were no fault code is there on it and no more misfiring or nothing shown in measuring blocks... And actually i re condition the engine last month due to cylinder one valve problem...😓 And at that time i regularly VCDS fault with misfiring and after i change the valve and re-condition the engine its all gone...💪🏼👍🏻... And i saw this red glowing manifold header inside the guard at night time and Let me check it thoroughly once again, about the red glowing issue on night time... And will take photo of that asap... Another thing please let me know, is that fabia 1.2 petrol engine vibrate slightly when idle... Or not???? The same engine of my friend vw polo has vibration 📳 on idle... Is that normal? If you have fabia the same engine kindly help me...🙏🏼 Thanks in advance....

[Breezy_Pete]

Look (on your car) at the temperatures shown for the cat in the two measuring blocks that I logged, 034 and 043. Compare with my numbers.

 

Does the car get used mostly for short journeys?

 

Some engine vibration at idle is normal, but should smooth out with a little more accelerator pedal.

[alenyohannan]

5 minutes ago, Wino said:

Look (on your car) at the temperatures shown for the cat in the two measuring blocks that I logged, 034 and 043. Compare with my numbers.

 

Does the car get used mostly for short journeys?

 

Some engine vibration at idle is normal, but should smooth out with a little more accelerator pedal.

 Yes... I m using the car mostly for short journeys... And i m little more curious about car care that's why i asked these queries... Don't feel but bro...🙏🏼😎

[alenyohannan]

12 minutes ago, Wino said:

Look (on your car) at the temperatures shown for the cat in the two measuring blocks that I logged, 034 and 043. Compare with my numbers.

 

Does the car get used mostly for short journeys?

 

Some engine vibration at idle is normal, but should smooth out with a little more accelerator pedal.

Definitely i will check the measuring blocks and post asap....🙏🏼😁

[alenyohannan]

On 25/01/2021 at 00:26, Wino said:

Look (on your car) at the temperatures shown for the cat in the two measuring blocks that I logged, 034 and 043. Compare with my numbers.

 

Does the car get used mostly for short journeys?

 

Some engine vibration at idle is normal, but should smooth out with a little more accelerator pedal.

Bro.. i checked the measuring blocks with vcds... And the result i attach herewith...

[sepulchrave]

Oh.

 

My.

 

God.

 

Over SIX HUNDRED degrees!

 

 

[Breezy_Pete]

On 24/01/2021 at 18:49, alenyohannan said:

And i saw this red glowing manifold header inside the guard at night time

 

I think that was the key piece of information that was missing from your first post.

Obviously, it would need to be brighter red to be daylight visible, which is what I think most of us assumed you meant.

I'll try to remember to look at ours in the dark one day soon.

[Phil866]

Interesting chart below. Same for all metals apparently.

[alenyohannan]

On 1/26/2021 at 14:57, Wino said:

 

I think that was the key piece of information that was missing from your first post.

Obviously, it would need to be brighter red to be daylight visible, which is what I think most of us assumed you meant.

I'll try to remember to look at ours in the dark one day soon.

Kindly note that in night and revert back please 🙏🏼🥺

[sepulchrave]

30 minutes ago, alenyohannan said:

Kindly note that in night and revert back please 🙏🏼🥺

 

Like I said, normal 

 

That is all.

[Breezy_Pete]

57 minutes ago, alenyohannan said:

Kindly note that in night and revert back please 🙏🏼🥺

Sure, no problem. 

[alenyohannan]

58 minutes ago, sepulchrave said:

 

Like I said, normal 

 

That is all.

I take the car to garage... The told me they didn't hav noticed these this till now 😂🤣