HEST light on too often...

[Brock]

08 Prostar with a 871. it's got a new turbo on it and I just did the egr tuneup to try and correct this issue to no avail.

My hest light comes on when I slow down darn near every other time so I see it 6 or so times a day. most times it goes out once I gain speed but once a day it'll stay on for a half hour.

Engine is a stock 500, dpf and doc cleaned in November but during my tuneup I did find my doser to be plugged to the max

I do not have a pyro or boost guage nor access to insite. going to get a shop to force a regen in coming days.

I haul 140,000lbs but even when empty, it does it.

Amy thoughts?

[dbl overdrive]

It's not a very good pic but looks like high temp exhaust light. It comes on during regen usually if you drop below a certain speed witch is set in insite.
It's basically a reminder for safety reasons. You can change it or even shut off if you like. But I would leave it.

[Brock]

That's exactly what it is and that was my understanding as to why it is coming on....... but it comes on so many times a day. I don't believe this truck should be doing a regen 6 times a day whixh would mean there is a issue.

[Rawze]

it all depends on how the truck is driven, etc. If there was a problem, you would be getting other alarms. Just post a screen shot here of the history in Insite. That would reveal more.

[Brock]

I should also mention that I have a code that pops up whenever I am on a hard pull with the engine around 1800rpm and the outside temperature is hot 75F +. will never do it if it's colder then that outside.

Engine module

VGT Actuator driver circuit (motor) - The smart VGT controller has detected incorrect stop limits or the VGT is unable to move to the closed position.

I am in a area where Noone seems to have insite so I am trying to get down to someone who does.

I didn't mention this because I thouggt it had gone away...... turns out it was just mild temps outside this last week.

[bazdan902]

Uhhhhh 1800rpm?? I'm going to guess that there's some heat damage to either the turbo or actuator running the engine that high with the amount of weight your pulling.... If not engine damage....

Maybe I'm wrong but I would say it probably not safe to push that engine to any more then 1600rpm or so.. Especially with that much torque load... Even when I'm driving my truck hard I won't do full throttle at those rpms. It must sound crazy at 1800 loll

[Brock]

I have a eaton autoshift and that's where it'll bring it up to on a hard pull. if I were driving a stick I wouldn't shift by 1600 with this kind of weight because I'd spend all day lugging my engine. You shift at 1600 with 140k while climbing and you'll find your next gear starting at 1100 wishing you hadn't done that.

Truck has a million miles on her and always ran this way and always ran this weight.

Once you start hauling this kind of weight, the rpm range you operate in changes. Cat is a good example..... at this weight, cat recommends 1600 to 1700 as a cruising rpm.

[scottydogtruck]

Did the shop do a proper re-calibration of the actuator AND the turbo using INSITE?

Also, did the HEST light come on like this before the turbo replacement?

Check your electrical connections around the turbo/EGR valve.....make sure they are on tight, and clean.

Just my two centavos......

[Brock]

(05-15-2016 )scottydogtruck Wrote:  Did the shop do a proper re-calibration of the actuator AND the turbo using INSITE?

Also, did the HEST light come on like this before the turbo replacement?

Check your electrical connections around the turbo/EGR valve.....make sure they are on tight, and clean.

Just my two centavos......

The shop seems to think they did it correct. I am going to verify this soon as I can.

The hest light started coming on exessively about a month after the new turbo which lead me to do the egr tuneup.