2LT high EGT low power (2 Viewers)

[4Ruster]

So I'm running a TD04L-13T on my 1986 2lt. I'm sure some of you have been following my build log for a while now.

I'm a little fed up with this little engine. I can't keep up with anything going up the hills to the lakes in the mountains, even my friends with 22r lifted trucks. I was barely holding 25 km/h in 2nd gear and my EGTs are well into the 800-1000F range. Boost was around 3-5psi. The turbo is used but I can push 13psi when I push it.

Where should I START with diagnosing?

 

[AussieHJCruza]

Where's your EGT probe and do you know where your timing is at?

 

[4Ruster]

Where's your EGT probe and do you know where your timing is at?

My egt probe is right before the turbo where all the cylinders collect. I don't know the exact timing but it's advanced a bit more then when I set it with the gauge last year.

 

[AussieHJCruza]

My egt probe is right before the turbo where all the cylinders collect. I don't know the exact timing but it's advanced a bit more then when I set it with the gauge last year.

Perfect, and are those EGTs above at WOT? Or are you lifting off the throttle to cool?

 

[4Ruster]

Perfect, and are those EGTs above at WOT? Or are you lifting off the throttle to cool?

Those are the EGTs under light throttle. I got into the throttle a bit because I was getting impatient and the needle shot past 1000⁰F so I crawled up in 1st gear the rest of the way. I noticed around a corner I tried to spin the tires in the snow like my friend in front of me and I got a bunch of black smoke out the back which is weird because I tuned my boost compensator pretty well down in town.

 

[RyanMiller]

what exhaust you running after the DP? I would be really interested to see your drive pressure ( pressure before the turbo.. just take the EGT probe out and put a gauge on some copper tubing. you want 1:1 boost/ drive pressure or better .. if you muffler or turbo are at fault that will show you.
my 2lt was spicy even with a flat top pump and td04-15, it did not like to lug much but it revved hard

 

[4Ruster]

what exhaust you running after the DP? I would be really interested to see your drive pressure ( pressure before the turbo.. just take the EGT probe out and put a gauge on some copper tubing. you want 1:1 boost/ drive pressure or better .. if you muffler or turbo are at fault that will show you.
my 2lt was spicy even with a flat top pump and td04-15, it did not like to lug much but it revved hard

I am running 2.5 straight pipe I welded up myself. I'm actually pretty proud of it. The downpipe is flattened a bit since I tucked it a little close to the block but it shouldn't be too big of a restriction.

 

[AussieHJCruza]

What do your EGTs go to at WOT? 1200f won't hurt it.

 

[AussieHJCruza]

Another question, do you have a functional wastegate or is it wired shut or something?

 

[4Ruster]

What do your EGTs go to at WOT? 1200f won't hurt it.

I rarely ever go WOT. When I did last on the highway, I think it hit 1000F

Another question, do you have a functional wastegate or is it wired shut or something?

Yes the wastegate starts to open at 8 PSI and stops building pressure past 13 PSI

 

[AussieHJCruza]

I rarely ever go WOT. When I did last on the highway, I think it hit 1000F

Yes the wastegate starts to open at 8 PSI and stops building pressure past 13 PSI

Ok, we need to know the max EGTs from a sustained WOT run to be able to comment properly - trying to work out if the low boost and therefore high EGTs are due to not enough fuel or if she's overfueled or maybe there's another issue.

How is the boost compensator set up? Do you know at what boost the rod starts to move and at what boost she's got full fuel?

 

[4Ruster]

Ok, we need to know the max EGTs from a sustained WOT run to be able to comment properly - trying to work out if the low boost and therefore high EGTs are due to not enough fuel or if she's overfueled or maybe there's another issue.

How is the boost compensator set up? Do you know at what boost the rod starts to move and at what boost she's got full fuel?

From when I was testing the compensator, it has full range on the pin, it starts adding fuel around 2 psi I'd say. I have it rotated to the deepest setting.

I can take the truck out tomorrow and see how hot I can get it. My friends call me James May because of my driving, WOT isn't something I like doing often.

 

[4Ruster]

 

[AussieHJCruza]

From when I was testing the compensator, it has full range on the pin, it starts adding fuel around 2 psi I'd say. I have it rotated to the deepest setting.

I can take the truck out tomorrow and see how hot I can get it. My friends call me James May because of my driving, WOT isn't something I like doing often.

Don't run the EGT gauge around the clock, but if it's getting over 1200f on a hard pull, I'd take fuel out on an IDI engine.

 

[TheBussman]

Sorry i haven't followed your build, maybe you already did but: compression test, check pump timing and injectors, valve timing, clearance. seems like you got a decent turbo on there. any smoke?

 

[AirheadNut]

You should be able to run 1000ºF sustained indefinitely on that engine, provided your cooling system can cope with the heat. Anything above 1200-1250ºF I would start backing off the throttle. I probably have a similar driving style with regards to WOT, the only time I have gone to the floor was on the dyno. On my TDI I generally run 1100ºF for hours on end at 120km/h, and will easily hit 1300ºF if I stay on the throttle on hills. I think you need more boost when cruising at speed, if I remember correctly my 2L-TE with stock CT20 would run 8-10psi at anything more than light loads. Max was 15psi.

 

[RyanMiller]

I rarely ever go WOT. When I did last on the highway, I think it hit 1000F

Yes the wastegate starts to open at 8 PSI and stops building pressure past 13 PSI

That turbo is on the map at 25psi still, you don’t need the WG opening that early. That forfeiting valuable spoolywind. Set the WG to open at 25psi or just disconnect it.. the 2l will survive 25psi mine was eating 30 happily. Also don’t expect boosting hard below 2K rpm, these thing need revs unlike a mammoth 6cyl

 

[bj70bc]

yes, less wastegate actuation (more boost), more throttle... to 1200f....1000 aint nothing
if you feel the need, then intercool it, and disable the wastegate (its wasting your boost too early)
if theres any black smoke at any point you have more than enough fuel, just need to burn it better, ie more air and revs

 

[4Ruster]

So on the way home today I got in the throttle a bit. 13 psi, pyrometer went up to around 1000F pretty slowly, I don't think it will go higher unless I'm really stressing the engine.

But holy s*** I damn near took a chunk out of the ozone layer, I looked behind me and all I could see was headlights peaking through a thick grey haze of smoke. It wasn't coming out black, more of a dark grey.

The truck seemed to pull better as the boost was rising through the 6 psi range around 2500 RPM then Thats when the smoke came out and I felt like I was accelerating slower.

Here's some more photos

 

[4Ruster]

Exhaust its pretty free flowing