Extremly high EGT

W

Whollahii

New Member
Hi!

Yesterday when I was out driving I ran in to a problem..

When I hit the gas and se the boost starts coming the exhaust temperature goes through the roof!

In a matter of seconds it goes from 600 degrees celsius to almost 1000 if I don't release the gas pedal. Like it's just spitting flames through the exhaust manifold. The EGT is located in the exhaust manifold and the lambda, which is fine, is located in the DP.

Before the problem started, I boosted the car with little gas in the tank and felt the car loosing power in the mid range. I realized my mistake and went to refill the tank. Drove off and all was fine until 5-10 minutes later when the problem started.

Any ideas?
 
PobodY

PobodY

Moderators
Staff member
Damaged injector? - I'm sure someone else had a problem like this (the manifold was glowing red), and it was down to one injector that was malfunctioning (causing that cylinder to run lean?).

Overall the mix ratio was OK so the lambda didn't pick anything up, but it may have caused further damage to that cylinder
 
campbellju

campbellju

Moderators
Staff member
What George has said, leaning out will raise EGT's.. I understand your boost level is the same, check your timing hasn't shifted as well.
 
Fast Guy

Fast Guy

Moderators
Staff member
Your egt sensor is in the manifold so it will read a lot hotter than one after the turbo. Mine's in the downpipe and goes upto around 840ish I think.

Might be worth getting an AFR gauge to see if it's running lean at all.
 
W

Whollahii

New Member
Yes I know but the egt has always been in the manifold but it is usually not as high as now, and it doesn't get high as fast as it does now.

Sorry when I said the lambda I meant the afr gauge. I have one and it says rich when I hit the gas..
 
W

Whollahii

New Member
PobodY said:
Damaged injector? - I'm sure someone else had a problem like this (the manifold was glowing red), and it was down to one injector that was malfunctioning (causing that cylinder to run lean?).

Overall the mix ratio was OK so the lambda didn't pick anything up, but it may have caused further damage to that cylinder
Click to expand...
How do I check if there is a faulty injector?
 
red reading

red reading

Active Member
Have you put a lower octane fuel in the car? The symptoms you are saying and the time of events looks like it.
 
W

Whollahii

New Member
red reading said:
Have you put a lower octane fuel in the car? The symptoms you are saying and the time of events looks like it.
Click to expand...
Well, I was on the phone when I was fueling the car so the thought that I wasn't paying attention to what I was doing has crossed my mind.. However I returned to the pump later and checked the one I think I was using and it was the high octane one.. And I didn't really think low octane could cause problems like this but maybe it can?

In that case I assume the fuel doesn't burn as easy as it should and therefore fuel is entering the exhaust mani and burns there? Right by the egt. And therefore the lambda seems correct?

I'll try filling the tank with high octane just to be sure before testing anything else..!
 
PobodY

PobodY

Moderators
Staff member
Running rich on boost? That's expected.

Running rich on idle or cruising? That's potentially a problem.
 
fubar andy

fubar andy

Moderator & N/W Rep
Staff member
Whollahii said:
How do I check if there is a faulty injector?
Click to expand...

Have the car ticking over (running) and put a screw driver to the injector body. Then with the screwdriver still touching the injector put your ear to the butt/handle of the screw driver.
You should then hear a "ticking sound" this is the injector spraying fuel into the chambers. If there is no ticking, a difference in sound or speed to the other injectors then there might be a problem!

I had similar issues to you a few years back and it was a leaking injector that was to blame. If you can try changing your injectors with some working standard units, that might make the problems go away/solve the issue?

As mentioned, make sure you've not put the wrong fuel in.

Was is your AFR showing when you are driving about on boost and off boost?

Also if its dark and your manifold isn't covered, drive a round normally, OFF BOOST at around 40-60mph for about 5 mins.
Stop, jump out and look under the bonnet in a dark area to see if your manifold is glowing (turbo and downpipe too).

I found my manifold to be glowing when off boost due to a faulty injector and my EGT going well into the 1000oC areas.

Click HERE to see my old thread about it, might be of use?
 
W

Whollahii

New Member
PobodY said:
Running rich on boost? That's expected.

Running rich on idle or cruising? That's potentially a problem.
Click to expand...
Running rich on bost, when not boosting it's behaving as exptected.

Yes I know it's supposed to run rich on boost and that's why I'm uncertain that the problem is not enough fuel..
 
W

Whollahii

New Member
fubar andy said:

Have the car ticking over (running) and put a screw driver to the injector body. Then with the screwdriver still touching the injector put your ear to the butt/handle of the screw driver.
You should then hear a "ticking sound" this is the injector spraying fuel into the chambers. If there is no ticking, a difference in sound or speed to the other injectors then there might be a problem!

I had similar issues to you a few years back and it was a leaking injector that was to blame. If you can try changing your injectors with some working standard units, that might make the problems go away/solve the issue?

As mentioned, make sure you've not put the wrong fuel in.

Was is your AFR showing when you are driving about on boost and off boost?

Also if its dark and your manifold isn't covered, drive a round normally, OFF BOOST at around 40-60mph for about 5 mins.
Stop, jump out and look under the bonnet in a dark area to see if your manifold is glowing (turbo and downpipe too).

I found my manifold to be glowing when off boost due to a faulty injector and my EGT going well into the 1000oC areas.

Click HERE to see my old thread about it, might be of use?
Click to expand...
Okay thanks I'll try that thing with the injectors. Will fill the tank to the top with high octane fuel first just to make sure that's not the problem.

I live in sweden so getting new injectors that fit and with the correct cc will take me a while. And there's a trackday next tuesday... Still having some hopes I'll get the car running proper by then :)

Will dig into your old thread. Thank you!
 
W

Whollahii

New Member
Nothing wrong with the injectors. Filled the tank with high octane fuel, so it's about 36 liters high octane and 14 liters that might be low octane. I'd say the car runs better but I'm not sure about the egt.. I never kept God track of it when I was driving casually before the problem so I'm not sure what it's supposed to be reading but when I hit the gas and reach around 1-1,1 bar boost the egt goes to high 800 almost 900 really fast. Is that normal? How hot is ok? Again the egt sensor is located in the exhaust manifold.
 
Fusion Ed

Fusion Ed

Active Member
Either lean (dont care what consult says as narrow band as campbellju says is of no use at all) or retarded timing. What amounts of ignition timing are you runnign when the manifold is red. Consider that EGT over 1000c pre turbo will probably damage ex valves sooner or later...
 
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