EGT too high. Exhaust Gas Temperature gauge, gage maximum [merged]

[RuBiCaNT5X]

Forgive the rookie question, but what exactly is the EGT telling you besides the temp of your exhaust? What does higher/lower temps tell you about the status of performance from a tuning point of view. Thanks fellas..

 

[Talon991]

I put a new fuel filter on to see if that will help.

 

[JoeyJigglesGSX]

I just had my car dyno tuned. So i obviously now have the Safc II and can see my knock. So i have a few questions on my exhaust temp and knock:

1. When i cruise on the high way and there is no traffic or its moving i am usually going around 80 (i drive to the beach every weekend so i leave real late when there is noone on the road, so im not trying to be cool or tough). If i get on it and am excelerating past 85mph my exhaust temp. starts going up to 1590 to a little over 1600. Is that normal?

2. What is the normal exhaust temp?

3. At what temp. is it bad and what should i do?

4. How do you know when you have knock? For some reason when i am decelerating in gear and i look at my AFC the knock goes crazy and when i get on it, it goes back to zero?

5. What about when i am just sitting there and the knock will show zero then start jumping around like crazy but never stay on a certain number? does that mean anything?

just some questions that i would like to be at peace with...thanks

 

[kicknurass4fun]

I am not to sure about the exhaust temp. Your car should have 0 knock. Since it is showing knock at idle and daily driving it could be phantom knock(like a ticking valve or somthing like that)

 

[JoeyJigglesGSX]

how bad is the ticking knock? Its weird though, it only shows when i have been driving my car for a long drive, but when i start it up there is nothing

 

[99gst_racer]

JoeyJigglesGSX - The knock that the SAFC shows is not correct. It is not capable to accurately display the correct amount of knock on our cars. Honestly, it's completely pointless to even hook that wire up...... Definitely don't tune with or use that number for anything.

 

[kicknurass4fun]

JoeyJigglesGSX - The knock that the SAFC shows is not correct. It is not capable to accurately display the correct amount of knock on our cars. Honestly, it's completely pointless to even hook that wire up...... Definitely don't tune with or use that number for anything.

I couldnt agree any more. I thought he was using a data logger. Which is somthing i would highly suggest investing in. Along with a wide band o2 sensor.

 

[JoeyJigglesGSX]

wow...thats crazy...i didn't know that about he knock sensor

well what about my exhaust temp being at like 1600 when getting on it in 5th gear past 85?

(again, im not trying to be cool or that i do this a lot, but i want to know if my car is ok)

 

[hystericfox]

I had a tuning issue with the MAFT before I started using the SAFC where I would be cruising and the EGT would jump like that. The logger was showing my front O2 voltage at .02 at the time. I re-tuned it and the problem went away. Do you have a datalogger or a wideband? Any CEL? My problem was strange, because I was getting both rich and lean high EGTs depending on how I was driving. Your EGT should be around 1450 farenheit or so.

 

[turbo2086]

Do not let it go past 1600. How much boost are you running? Because when the temperature gets high like that, thats usually a sign of leaning out. Also, where is your EGT mounted? How far is the probe in?

 

[99gst_racer]

well what about my exhaust temp being at like 1600 when getting on it in 5th gear past 85?

Yes, 1600* EGT's are not safe at all; the melting point of aluminum is 1650* F. I've only had EGT's that high at WOT at 140+ MPH (which is almost never).
At 85 mph in 5th, I honestly can't remember where I'm usually at. I believe somewhere around 1300*.

Tuning a SAFC without a logger is basically tuning blind. Definitely invest in some sort of datalogger. Also, I'd recommend getting a wideband O2 set-up if your budget allows.

Once you have a logger (and possibly a WB), then you can go to work on the SAFC and hopefully get a much better tune on the engine to potentially bring those EGTs down a bit.

 

[matt97gst]

Cruising at 85+ my egts are always 1550*+ (but never over 1600). I thought this was the norm but I've never really seen many other people post what their temps are at 85mph cruising. I'm usually driving for an hour when I'm at these speeds so hopefully being at 1550-1600 for an hour isn't hurting anything.

 

[kraka]

My EGT usually reads somewhere in the 14K-15K range while I am cruising at much lower gears like 3rd or 4th...I am probably only going 40-45mph and the gauge will show 1450+ degrees everytime...How bad is this temp?

 

[99gst_racer]

Well, I monitored my EGT gauge closely all the way to work today. It's a 22 mile Interstate drive and I was traveling at 85-90 mph the whole way. It stayed in the 1200-1250*F range the entire time. I slowed down to 70mph about 1 mile before my exit and it quickly went back down to 1100*.

You guys might me running a little on the lean side if you have EGT's reading high like yours.

 

[JoeyJigglesGSX]

wow...thanks for the replys

the boost i am running is 16.5

no i dont have a datalogger, i dont know anything about tuning so i cant speak much about it. I had it dyno tuned so i thought that was the safest way, where they can monitor everything, right?

When i drive normally it is around 1300 and everything is cool...when im at 50-60 im at still 1350 maybe 14000, but only when i am at lik 80 and up and just sort of getting on it does it go up to 1600.

also i have no idea on how far down the probe is, i didnt do it. A shop did for me.

What do you guys recommend that i do? Wouldnt fuel cut come into play if i am really that lean?

 

[matt97gst]

Well, I monitored my EGT gauge closely all the way to work today. It's a 22 mile Interstate drive and I was traveling at 85-90 mph the whole way. It stayed in the 1200-1250*F range the entire time. I slowed down to 70mph about 1 mile before my exit and it quickly went back down to 1100*.

You guys might me running a little on the lean side if you have EGT's reading high like yours.

Where do you have your probe?

 

[99gst_racer]

no i dont have a datalogger

Put it next on your list of parts to buy. You can never go wrong with a datalogger.

i dont know anything about tuning so i cant speak much about it.

Definitely learn more about tuning in general and the basic functions of the SAFC before you go any furthur. I'd hate to see you run high boost with a lean mixture and let the engine be destroyed.

I had it dyno tuned so i thought that was the safest way, where they can monitor everything, right?

Did they use a wideband when tuning it? Are they very familiar with the SAFC?

What do you guys recommend that i do?

Get a logger and a wideband and see if you're running lean or not.

Wouldnt fuel cut come into play if i am really that lean?

Fuel cut occurs when the MAS meters too much airflow. Your problem could simply be that the SAFC is set to take out too much fuel, causing you to run lean/hot.

Where do you have your probe?

My probe is right after the turbo. (I've heard too many horror stories about the probes mounted in the manifolds - sometimes then can break off and pass through the turbine blades.)

 

[autox4fun]

You really should have the probe mounted as close to the head has possible BEFORE your turbo on the leanest cylinder (I have mine tapped for cylinder 2) most put them in Cylinder 1 ( which is closest to the timing belt)
You really want to see what is coming out of the head.
I would suggest you to have the probe placed in the manifold.... I have had a egt probe in my manifold for over 5 years never having a problem (TRE probe)

You may find your temp's to be right in line....

 

[99gst_racer]

You really should have the probe mounted as close to the head has possible BEFORE your turbo on the leanest cylinder (I have mine tapped for cylinder 2) most put them in Cylinder 1 ( which is closest to the timing belt)
You really want to see what is coming out of the head.
I would suggest you to have the probe placed in the manifold.... I have had a egt probe in my manifold for over 5 years never having a problem (TRE probe)

You may find your temp's to be right in line....

Yeah, I know a manifold mounted probe is ideal..... From what I've read, many people mount it after the turbo and then add 100-150* to what the gauge reads and it should be pretty accurate. IDK, I have to pull my manifold off this week, so maybe I'll drill and tap it in the #1 runner and I'll post my differences in readings.

Randy - I can mount the sensor on the underside of the manifold, right? It would make it so much easier not having to drill through my JM Fab. heatshield......

 

[autox4fun]

To keep it clean looking sure i don't see why it would change anything.... but will it be easy thats the question (if your not pulling the manifold)....
let me know the change
I've thought of running two, have a switch or relay to pick which one... maybe if you have a second one (cheap from your work) you could do the same ... just a thought.

 

[matt97gst]

Yeah, I know a manifold mounted probe is ideal..... From what I've read, many people mount it after the turbo and then add 100-150* to what the gauge reads and it should be pretty accurate. IDK, I have to pull my manifold off this week, so maybe I'll drill and tap it in the #1 runner and I'll post my differences in readings.

Randy - I can mount the sensor on the underside of the manifold, right? It would make it so much easier not having to drill through my JM Fab. heatshield......

That'd be very helpful to post the differences seen between the manifold and downpipe. Finally someone can give an accurate difference of the two.

 

[sublime_ing]

The type of cams you have will also effect where your egts will be while cruising. EGT's are usually highest at peak torque. With my stock cams my egts were around 810*C cruising in 5th at around 80mph/4k rpms. When I switched to Crower stage II cams, in the same situation on the highway my egts are now around 750*C. If your car is properly tuned, I wouldnt worry about it.

 

[JoeyJigglesGSX]

ok, well i really kept my eye on my egt gauge (first off it mounted on the #1 runner) and everything seems to be cool. I dont know if something was just weird that day or what, but when i am at 80 mph cruising my egt temp is at around 1300 and the rpms are at what about 3500-4000? It is only if i wanted to really get on it did the temp go up and it went to about 1500 maybe 1550...so is that ok? and these are at speeds over 100 which i am almost never at...i was just testing everything out

 

[ChiGGz]

Is EGT temps that major of a concern when I have DSMLink and can monitor knock continuously? I mean, knock is a product of lean fuel trims, which results in high temperatures am I right?

What I'm really trying to ask is, do I have to worry too much about thermal meltdown when I'm using DSMLink to tune. A wideband O2 will be coming in the future just not yet.

 

[DSMcrazy3]

Not if you know how to tune with your devices.. If you don't know how, you can definitely mis-tune and screw some things up.

It's just a matter of your knowledge with your equipment.

 

[hottboost]

Alright, finished EGT intall today. Few runs at 18PSI and egts went to about 780 C! It is mounted in the o2 housing right on the bend. I know every vehichle is different but just trying to get a feel if this would be normal. I also know the main purpose is to monitor with it and make sure there is never a drastic change. Thanks in advance. Mods in profile but havent done the 550's or SAFC Yet. Tried everything from 14psi to 19psi and timing still pulls around 4-6 at 3200 rpms. Should I give up on that untill i do the safc.