Uber High EGT's When Cruising

[kylush]

Ok, so I recently installed my Defi EGT and boost gauges, and AEM wideband and noticed that when cruising at about 75 on the freeway I am getting some reallly really high egts!

Like my wideband is reading normal AFR's like just hangs right around 14.7, but my EGT's are up over 1600 degrees farenheit, I usually cruise for like 100 miles or more on the freeway when I'm going back from college so I've seen it like this a couple times now. Last time I was coming back up to school from back home when I started going up an incline and started hitting less vacuum or a little boost and there was more load on the motor my EGT's got up over 2000 degrees farenheit several times!

Also when i start my car now it runs like shit till it's warmed up even though it isn't that cold out now. Like i can't take off without it dying unless i rev it up and slip clutch real slowly.

Also I think I may have a boost leak cause it seems i've lost power and the turbo is louder so that could have something to do with it i'm thinking...

Oh and problem number 3. Does anyone else have problems with their manifold and turbo to manifold bolts vibrating loose and backing out?! I've had my manifold bolts do it a couple times now and this winter i couldn't work on my car much cause i don't have a heated garage and it was so cold out. Anyhow it lost power over time and sounded like it had a major exhaust leak. Well checked it out a couple weeks ago and two of the bolts holding the turbo to the manifold had backed pretty much all the way out, but the heat sheild stopped them and one was about halfway out and there was a couple mm gap between the turbo and the manifold. Tightened everything up and now i can kinda hear the same noise again so I'm thinking it happened again.

Hopefully that all makes sense. Wasn't sure if I should start several different threads for all this other stuff or just put it in one thread. Thanks

 

[rush2252]

Everything your describing points to BOOST LEAK. Search it... you can build a boost leak tester fairly cheap and this is usually 80% of problems associated with poor performing BOOSTED cars.

And yes I just discovered the bolts on my 2g were almost backed completely out as well. Im not sure there is a thread locker that will hold upto 1500 temps but try a new gasket. If its worn out and the bolts are stretched this could be an issue as well. Be careful I snapped the head off one of mine when tightening it with and end wrench

 

[kylush]

Yeah it sucks. Thats the exact same thing I was thinking too thread locker but what kinda thread locker is gonna stand up to the high temps involved.

And yes I intend to check for boost leaks and recheck my manifold bolts. Unfortunately I am going to school 170 miles from home and my boost leak tester and air compressor are there so I have to go home this weekend and do it. I've also been insanely busy these last couple weeks of the semester so that makes it hard, but I intend to check it over this weekend!

 

[rush2252]

Yeah it sucks. Thats the exact same thing I was thinking too thread locker but what kinda thread locker is gonna stand up to the high temps involved.

And yes I intend to check for boost leaks and recheck my manifold bolts. Unfortunately I am going to school 170 miles from home and my boost leak tester and air compressor are there so I have to go home this weekend and do it. I've also been insanely busy these last couple weeks of the semester so that makes it hard, but I intend to check it over this weekend!

I would check it before going on the 3 hour trip. Im not for sure on heat soak but id imagine 2000+ temps on the exhaust side arent doing so well on the oil temps of the turbo and or surrounding components. Even if you dont have a boost leak tester handy at least try checking all the obvious intercooler piping etc for leaks.

 

[kylush]

just took a look at it and 4 of those stupid little vaccum caps on the throttle body are cracked and look like they could be leaking and one of my problematic manifold bolts has rattled loose again and fell out somewhere. There was allready one missing in the middle cause the hole in the head was stripped out so that could pose a problem...

 

[lacroixdp]

Oh and problem number 3. Does anyone else have problems with their manifold and turbo to manifold bolts vibrating loose and backing out?!

Loctite (red) will cure this problem. Just to warn you - it is VERY hard to remove bolts you use it on - I guess that's the point though eh?

 

[blownturbotsi]

I was always told when cruising to try to keep my EGT's ~1400 or less. 1600-2000 is pretty hot and I wouldn't test that anymore. Cruise at lower speeds if you can. It's a pain, but I have had to drive ~55mph for ~7hrs on a 4hr trip because of my EGT's being high.

 

[RvlutionMtrsprt]

So.. a boost leak will make your egt's high?? Boost leak = rich = lower egt's???
As for your bolts backing out you need to use 2 convex washers on each bolt and torque to spec. Mitsu part # is MR187848.

 

[blownturbotsi]

So.. a boost leak will make your egt's high?? Boost leak = rich = lower egt's???
As for your bolts backing out you need to use 2 convex washers on each bolt and torque to spec. Mitsu part # is MR187848.

Being too rich will also cause high EGT's. I don't believe that this is the case for the OP, though.

 

[kylush]

I was always told when cruising to try to keep my EGT's ~1400 or less. 1600-2000 is pretty hot and I wouldn't test that anymore. Cruise at lower speeds if you can. It's a pain, but I have had to drive ~55mph for ~7hrs on a 4hr trip because of my EGT's being high.

I understand that for now, but I would rather try and fix it than just have to deal with the annoyance. And yeah its not a rich or lean condition thats causing this cause alot of the time my egts are up over 1600F my AFR's are like a perfect 14.7... when cruising of course.

 

[blackjdm90]

Loctite (red) will cure this problem. Just to warn you - it is VERY hard to remove bolts you use it on - I guess that's the point though eh?

It works!! too well actually, i broke some bolts when upgrading manifolds!!