Turbo lagging only when fully warm?

[Texas~KR]

I have the IDP Xrace tune. I really don't travel much distance to work. So when cold, half warmed, or during the first few half throttle runs, the truck will go from 5 to 30psi in an instant, and 1/3 throttle is all that is needed to get there and feel the hard acceleration. It runs perfect.
BUT, when the truck is fully warm on long drives and several pulls, around 200 degrees, I have to go WOT just to get 30psi, and it takes a bit longer to reach full boost. It also doesn't feel as fast as when cold. It's like the timing was pulled badly.

IDK if this has to do with the tune file, or maybe the turbo VGT is sticking when hot? I'm not a diesel mechanic at all so...

[sleeper1]

Yeah now that you mention it, my truck does the same thing. I have Matt's SRL and it definitely has a lot less turbo lag in the morning when it's cold. I haven't noticed what the boost was doing though. It's usually too early for me to care lol. I'm going to look tomorrow morning though and see what it does. I'm interested to hear if anyone knows why it does this.

[blueovalman14]

sounds like the turbo needs to be cleaned!

[sleeper1]

Well mine was just cleaned not too long ago....I run it too hard for it to get dirty that fast. If the turbo was dirty, wouldn't it run worse when it's cold, where as when it's hot the heat would help loosen up any oil and crud?

[PGreenSVT]

I would look into your High Pressure Oil system. May be developing a leak and loosing some pressure when warm that could account for what you are experiencing.

[sleeper1]

Damnn funny you say that, I thought I had a HPO problem about a month ago. I checked my ICP pressure with an auto enginuity scanner and I was getting 580psi when warm. I thought this was sufficient so I ruled up a HPO leak and figured it was weak injectors. I guess I should hook it up first this in the morning and see if my readings start out higher and decline as it warms up.

Edit: My curiosity wouldn't let me wait until the morning so I just went out and checked it. The truck had been sitting for 4 hours so it was cold enough for the test. At first start, I was getting 1000-1050psi at idle. I drove around until it reached operating temp, and it was back down to 580psi. Does this sound like a leak?

[hazard]

Bump! I too am curious about this, my extreme street is VERY jumpy when cold but not for long a mile down the road and its normal to me...I wish it was as jumpy all the time like it is when cold lol not that it don't have good power but it would be nice. Its done this since I first tuned it which was over a year and a half ago

[smokersteve]

I agree, there might be an oil leak, although I could be wrong

[alwil]

Originally Posted by sleeper1

Damnn funny you say that, I thought I had a HPO problem about a month ago. I checked my ICP pressure with an auto enginuity scanner and I was getting 580psi when warm. I thought this was sufficient so I ruled up a HPO leak and figured it was weak injectors. I guess I should hook it up first this in the morning and see if my readings start out higher and decline as it warms up.

Edit: My curiosity wouldn't let me wait until the morning so I just went out and checked it. The truck had been sitting for 4 hours so it was cold enough for the test. At first start, I was getting 1000-1050psi at idle. I drove around until it reached operating temp, and it was back down to 580psi. Does this sound like a leak?

My ICP reads the same way hot and cold my max ICP I can see is 3700 at wot......I am leaning towards a weak hpop.
My IPR duty cycle reads 20.4 at idle and 71.3 at wot......also I just replaced my icp sensor

[sleeper1]

Originally Posted by alwil

My ICP reads the same way hot and cold my max ICP I can see is 3700 at wot......I am leaning towards a weak hpop.
My IPR duty cycle reads 20.4 at idle and 71.3 at wot......also I just replaced my icp sensor

How can you tell if you have a leak in the HPO system vs. a weak HPOP based on based on ICP numbers? I haven't checked my ICP at wot. What should the IPR duty cycle normally be at? I also just replaced my ICP sensor.