6.0 turbo question
#1
09-11-2016, 06:08 AM
6.0 turbo question
Hi all...
First off I apologize if this is posted somewhere already (I am operating off of a phone so searching and reading are a little harder) I figured it may be quicker to just post and ask.
Ok 2006 F550 6.0 170k miles..
Two weeks ago I had a few issues and kept going into limp mode.. found out it was the APS in the pedal... Replaced (still had old style...put new style pedal with bracket in) man what a difference. Only got the truck in April.. must have been going bad for a while. Drives completely different now.. accelerates like crazy (compared to before).
So..then a week later over the holiday weekend I did the following...
-EGR delete (only the hardware... What I mean is to avoid a code I left the egr valve plugged in but just zip tied in the engine compartment)
-BLUE SPRING UPGRADE
-New fuel filters (top and bottom)
-Cleaned out the water/fuel separator (took it all apart... It was gunked up and I was getting codes)
-Turbo clean
So in putting it all back together I tested it and runs like a champ. Way more power than what I had previously and WAYYY better mileage.
The turbo boost BEFORE all of this was 24-25psi... After I was done it was about the same.. with GREAT ACCELERATON!!
NOW, a week later... Turbo boost is 19-20 psi.. upon inspecting I noticed a small fuel leak at the top filter housing (my mistake I had not gotten a fitting completely tight) so I repaired that and no more leak. Turbo boost went up to about 20-21 psi...so I'm still short on the boost.
I am noticing what seems to me a loss of power, even just from a week ago... I am suspecting it may be due to lower turbo boost. My next step is to get new upper and lower turbo boots (have no idea how old these are and after removing them and installing them for the egr delete I believe they may be worn to much)
I've checked the turbo boost sensor hose for holes... None found. (Common problem)
I don't know where to go next. I need to have this working correctly to put my mind at ease because soon I need to get coal for the winter to keep my family warm.
Help... Anyone... Please. Lol.
I do have AE that I can check all the sensors etc and being that I am sort of new to it I am still learning it... So if someone asks for more info... Tell me what you need and I will look it up the best I can on AE.
Thanks.
First off I apologize if this is posted somewhere already (I am operating off of a phone so searching and reading are a little harder) I figured it may be quicker to just post and ask.
Ok 2006 F550 6.0 170k miles..
Two weeks ago I had a few issues and kept going into limp mode.. found out it was the APS in the pedal... Replaced (still had old style...put new style pedal with bracket in) man what a difference. Only got the truck in April.. must have been going bad for a while. Drives completely different now.. accelerates like crazy (compared to before).
So..then a week later over the holiday weekend I did the following...
-EGR delete (only the hardware... What I mean is to avoid a code I left the egr valve plugged in but just zip tied in the engine compartment)
-BLUE SPRING UPGRADE
-New fuel filters (top and bottom)
-Cleaned out the water/fuel separator (took it all apart... It was gunked up and I was getting codes)
-Turbo clean
So in putting it all back together I tested it and runs like a champ. Way more power than what I had previously and WAYYY better mileage.
The turbo boost BEFORE all of this was 24-25psi... After I was done it was about the same.. with GREAT ACCELERATON!!
NOW, a week later... Turbo boost is 19-20 psi.. upon inspecting I noticed a small fuel leak at the top filter housing (my mistake I had not gotten a fitting completely tight) so I repaired that and no more leak. Turbo boost went up to about 20-21 psi...so I'm still short on the boost.
I am noticing what seems to me a loss of power, even just from a week ago... I am suspecting it may be due to lower turbo boost. My next step is to get new upper and lower turbo boots (have no idea how old these are and after removing them and installing them for the egr delete I believe they may be worn to much)
I've checked the turbo boost sensor hose for holes... None found. (Common problem)
I don't know where to go next. I need to have this working correctly to put my mind at ease because soon I need to get coal for the winter to keep my family warm.
Help... Anyone... Please. Lol.
I do have AE that I can check all the sensors etc and being that I am sort of new to it I am still learning it... So if someone asks for more info... Tell me what you need and I will look it up the best I can on AE.
Thanks.
#2
09-11-2016, 08:30 AM
-Did you clear the MAP nipple on the intake manifold with a straw from a can of brake cleaner? This nipple gets clogged from the EGR and often limits boost because the MAP sensor can't correctly read.
-Did you clean your EBPS, tube, and fitting? These also play a role in the truck boosting properly. Without it, the truck can't accurately how much exhaust pressure is in the manifold, so it doesn't know if the fuel its dumping marches the amount of boost.
-Did you clean your MAF? This is where it all starts.
-Did you clean your EBPS, tube, and fitting? These also play a role in the truck boosting properly. Without it, the truck can't accurately how much exhaust pressure is in the manifold, so it doesn't know if the fuel its dumping marches the amount of boost.
-Did you clean your MAF? This is where it all starts.
#3
09-11-2016, 10:53 AM
Fleet Mechanic
What toreador said, plus I would add:
Check the (2) boots between the turbo & intercooler. If they look remotely bad I would replace them.
Being a 2006 I assume you still have the plastic tube from the intercooler back to the motor? Those are notorious for leaking, mostly down at the "accordion" section at the bottom. Pull it off and inspect. The fix is to retrofit to the 2003/2004 style metal tube with boots. There's a complete kit for about $120.
Also check the intercooler itself. They like to leak at the seam on the passenger side. usually evidences by oil on the seam or in extreme cases you can actually see the gasket sticking out. Just lift the plastic behind the grille to inspect it.
Check the (2) boots between the turbo & intercooler. If they look remotely bad I would replace them.
Being a 2006 I assume you still have the plastic tube from the intercooler back to the motor? Those are notorious for leaking, mostly down at the "accordion" section at the bottom. Pull it off and inspect. The fix is to retrofit to the 2003/2004 style metal tube with boots. There's a complete kit for about $120.
Also check the intercooler itself. They like to leak at the seam on the passenger side. usually evidences by oil on the seam or in extreme cases you can actually see the gasket sticking out. Just lift the plastic behind the grille to inspect it.
#4
09-11-2016, 12:45 PM
-Did you clear the MAP nipple on the intake manifold with a straw from a can of brake cleaner? This nipple gets clogged from the EGR and often limits boost because the MAP sensor can't correctly read.
-Did you clean your EBPS, tube, and fitting? These also play a role in the truck boosting properly. Without it, the truck can't accurately how much exhaust pressure is in the manifold, so it doesn't know if the fuel its dumping marches the amount of boost.
-Did you clean your MAF? This is where it all starts.
-Did you clean your EBPS, tube, and fitting? These also play a role in the truck boosting properly. Without it, the truck can't accurately how much exhaust pressure is in the manifold, so it doesn't know if the fuel its dumping marches the amount of boost.
-Did you clean your MAF? This is where it all starts.
I had not at the time of the posting... but I did do all three today. Instead of it helping, the boost actually went down a little more. I did squeeze the boots while I was in there looking again for cracks... and since it went down more, I am thinking its a boot issue. (I hope..)
Any other ideas before I order boots and the cac tube kit from riffraff?
#5
09-11-2016, 12:48 PM
What toreador said, plus I would add:
Check the (2) boots between the turbo & intercooler. If they look remotely bad I would replace them.
Being a 2006 I assume you still have the plastic tube from the intercooler back to the motor? Those are notorious for leaking, mostly down at the "accordion" section at the bottom. Pull it off and inspect. The fix is to retrofit to the 2003/2004 style metal tube with boots. There's a complete kit for about $120.
Also check the intercooler itself. They like to leak at the seam on the passenger side. usually evidences by oil on the seam or in extreme cases you can actually see the gasket sticking out. Just lift the plastic behind the grille to inspect it.
Check the (2) boots between the turbo & intercooler. If they look remotely bad I would replace them.
Being a 2006 I assume you still have the plastic tube from the intercooler back to the motor? Those are notorious for leaking, mostly down at the "accordion" section at the bottom. Pull it off and inspect. The fix is to retrofit to the 2003/2004 style metal tube with boots. There's a complete kit for about $120.
Also check the intercooler itself. They like to leak at the seam on the passenger side. usually evidences by oil on the seam or in extreme cases you can actually see the gasket sticking out. Just lift the plastic behind the grille to inspect it.
but I do not know if I want to pay the extra money for the riffraff boots for that side and new ones for the hot side... Cooler is good... no leaks there it appears.
Anything else to check? I did clean all three sensors that Toreador said and the boost went down even farther. See above reply to his post.
#6
09-11-2016, 03:33 PM
Toreador,
I had not at the time of the posting... but I did do all three today. Instead of it helping, the boost actually went down a little more. I did squeeze the boots while I was in there looking again for cracks... and since it went down more, I am thinking its a boot issue. (I hope..)
Any other ideas before I order boots and the cac tube kit from riffraff?
I had not at the time of the posting... but I did do all three today. Instead of it helping, the boost actually went down a little more. I did squeeze the boots while I was in there looking again for cracks... and since it went down more, I am thinking its a boot issue. (I hope..)
Any other ideas before I order boots and the cac tube kit from riffraff?
Post number 4: https://www.ford-trucks.com/forums/6...ml#post4956068
Keep in mind, because the turbo shows less boost isn't a bad thing. If anything the turbo may have been overboosting to compensate for the inaccurate readings.
Someone who installs a billet wheel on their truck...will get upset because they're now seeing less boost, however, the lower boost number means a higher volume of air is making it to the cylinders. The turbo doesn't have to build as much boost because it's flowing a higher volume of air.
#7
09-11-2016, 03:56 PM
Counterintuitive but true. Pressure comes from the air that's essentially jammed up between the compressor and the intake valves; at the same input flow, lower pressure means air is flowing through the outlet faster.
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#8
09-12-2016, 08:44 PM
Boost pressure discussion aside, the fact that you're losing power / throttle response says there's a problem either at the PCM-commanded, high pressure oil activated turbo or with any number of other areas as you've been "inside" with the EGR delete --- don't rule out the HPOP, injectors, exhaust leaks, and fuel pressure. My gut feel is it's something other than the actual VGT, but there's always "mis-aligned" connections, exhaust leaks, etc that plague us after EGR deletes.
Not sure if you have Ford IDS or what scanner you're using but first, baseline your PIDS for BARO, MAP, EP --- they should all be within 1.5 PSI of one another Key On Engine Off. Also check for small oil leaks at the back of the engine (post EGR delete).
Then AFTER the PCM "re-learn" you might want to start the VGT tests (First of Five Tests below):
Low RPM Operation
Highlight the RPM PID and command the engine to approximately 1200 RPM and the EGRDC# PID to 0%.
Then highlight the VGTDC# and increase it to 85% and record the EBP_G & MGP
Next command the VGT to 0% and record the EBP_G and MGP PIDs
At 85% the EBP_G should be below 7.3 PSI and MGP should be above 0.87 PSI.
At 0% the EBP_G should be below 0.73 PSI and MGP should be below 0.45 PSI.
Next test of the VGT is higher RPM (3500)..........and so on........
Not sure if you have Ford IDS or what scanner you're using but first, baseline your PIDS for BARO, MAP, EP --- they should all be within 1.5 PSI of one another Key On Engine Off. Also check for small oil leaks at the back of the engine (post EGR delete).
Then AFTER the PCM "re-learn" you might want to start the VGT tests (First of Five Tests below):
Low RPM Operation
Highlight the RPM PID and command the engine to approximately 1200 RPM and the EGRDC# PID to 0%.
Then highlight the VGTDC# and increase it to 85% and record the EBP_G & MGP
Next command the VGT to 0% and record the EBP_G and MGP PIDs
At 85% the EBP_G should be below 7.3 PSI and MGP should be above 0.87 PSI.
At 0% the EBP_G should be below 0.73 PSI and MGP should be below 0.45 PSI.
Next test of the VGT is higher RPM (3500)..........and so on........
#9
09-13-2016, 05:07 AM
Boost pressure discussion aside, the fact that you're losing power / throttle response says there's a problem either at the PCM-commanded, high pressure oil activated turbo or with any number of other areas as you've been "inside" with the EGR delete --- don't rule out the HPOP, injectors, exhaust leaks, and fuel pressure. My gut feel is it's something other than the actual VGT, but there's always "mis-aligned" connections, exhaust leaks, etc that plague us after EGR deletes.
Not sure if you have Ford IDS or what scanner you're using but first, baseline your PIDS for BARO, MAP, EP --- they should all be within 1.5 PSI of one another Key On Engine Off. Also check for small oil leaks at the back of the engine (post EGR delete).
Then AFTER the PCM "re-learn" you might want to start the VGT tests (First of Five Tests below):
Low RPM Operation
Highlight the RPM PID and command the engine to approximately 1200 RPM and the EGRDC# PID to 0%.
Then highlight the VGTDC# and increase it to 85% and record the EBP_G & MGP
Next command the VGT to 0% and record the EBP_G and MGP PIDs
At 85% the EBP_G should be below 7.3 PSI and MGP should be above 0.87 PSI.
At 0% the EBP_G should be below 0.73 PSI and MGP should be below 0.45 PSI.
Next test of the VGT is higher RPM (3500)..........and so on........
Not sure if you have Ford IDS or what scanner you're using but first, baseline your PIDS for BARO, MAP, EP --- they should all be within 1.5 PSI of one another Key On Engine Off. Also check for small oil leaks at the back of the engine (post EGR delete).
Then AFTER the PCM "re-learn" you might want to start the VGT tests (First of Five Tests below):
Low RPM Operation
Highlight the RPM PID and command the engine to approximately 1200 RPM and the EGRDC# PID to 0%.
Then highlight the VGTDC# and increase it to 85% and record the EBP_G & MGP
Next command the VGT to 0% and record the EBP_G and MGP PIDs
At 85% the EBP_G should be below 7.3 PSI and MGP should be above 0.87 PSI.
At 0% the EBP_G should be below 0.73 PSI and MGP should be below 0.45 PSI.
Next test of the VGT is higher RPM (3500)..........and so on........
I did remove hot side boots, wash and inspect under a bright light. I could NOT find one crack or tear in them. (Almost amazingly...) So if we stick to the turbo boost for a moment... Then I would have to say possible leak on the cac and it's time to get rid of the plastic tube
(my pressure did go back up to 20-21psi after reinstalling the boots so perhaps I did have a small clamp leak I was not aware of)It is true that if there was less boost pressure there could be more air flowing into the cylinders...however I believe that from factory the boost on These was to be around 25-28psi... (Correct me if I am wrong please as I would like to know) so I still believe I am low.
Definitely is a loss of power since the delete. (Not dramatic but I can tell the difference)
I have Auto Enginuity w/ the Ford expansion so now that I know what to look at I will do my best to get to that tonight (if I don't have to work till some unnaturally late time tonight) I am not sure on how to perform all of them on AE. It is new to me and there is not a whole ton of resource material with it.
Are all the tests you mentioned Key on Engine Off? (Just so I don't get it wrong) I can understand issues after the delete... But to have it work so well for a week and then to act up... Seems weird. Looks like my mpg MAY now be dropping a little also..but after just a quarter tank I am not sure as of yet. Need to burn more to get a better average.
Power band testing showed all cylinders pulling their own weight equally... So if I am correct in my thinking if I had a bad injector it would show up on the graph on AE. So I think an injector issue is not the cause. I did check for exhaust leaks and have not found any... (One of my first thoughts for low boost was a exhaust leak before the turbo and I check that)
Pcm relearn... Going to have to research the process on that. Not entirely sure of the process of that.
I would ask is it a bad move to order a upgraded cac tube bit the more i think about it... Even if that's not the issue it's better to get rid of the plastic crap tube anyway.
Thanks
#10
09-18-2016, 09:39 AM
Ok sorry been off line for a day...
I did remove hot side boots, wash and inspect under a bright light. I could NOT find one crack or tear in them. (Almost amazingly...) So if we stick to the turbo boost for a moment... Then I would have to say possible leak on the cac and it's time to get rid of the plastic tube (my pressure did go back up to 20-21psi after reinstalling the boots so perhaps I did have a small clamp leak I was not aware of)
It is true that if there was less boost pressure there could be more air flowing into the cylinders...however I believe that from factory the boost on These was to be around 25-28psi... (Correct me if I am wrong please as I would like to know) so I still believe I am low.
Definitely is a loss of power since the delete. (Not dramatic but I can tell the difference)
I have Auto Enginuity w/ the Ford expansion so now that I know what to look at I will do my best to get to that tonight (if I don't have to work till some unnaturally late time tonight) I am not sure on how to perform all of them on AE. It is new to me and there is not a whole ton of resource material with it.
Are all the tests you mentioned Key on Engine Off? (Just so I don't get it wrong) I can understand issues after the delete... But to have it work so well for a week and then to act up... Seems weird. Looks like my mpg MAY now be dropping a little also..but after just a quarter tank I am not sure as of yet. Need to burn more to get a better average.
Power band testing showed all cylinders pulling their own weight equally... So if I am correct in my thinking if I had a bad injector it would show up on the graph on AE. So I think an injector issue is not the cause. I did check for exhaust leaks and have not found any... (One of my first thoughts for low boost was a exhaust leak before the turbo and I check that)
Pcm relearn... Going to have to research the process on that. Not entirely sure of the process of that.
I would ask is it a bad move to order a upgraded cac tube bit the more i think about it... Even if that's not the issue it's better to get rid of the plastic crap tube anyway.
Thanks
I did remove hot side boots, wash and inspect under a bright light. I could NOT find one crack or tear in them. (Almost amazingly...) So if we stick to the turbo boost for a moment... Then I would have to say possible leak on the cac and it's time to get rid of the plastic tube
(my pressure did go back up to 20-21psi after reinstalling the boots so perhaps I did have a small clamp leak I was not aware of)It is true that if there was less boost pressure there could be more air flowing into the cylinders...however I believe that from factory the boost on These was to be around 25-28psi... (Correct me if I am wrong please as I would like to know) so I still believe I am low.
Definitely is a loss of power since the delete. (Not dramatic but I can tell the difference)
I have Auto Enginuity w/ the Ford expansion so now that I know what to look at I will do my best to get to that tonight (if I don't have to work till some unnaturally late time tonight) I am not sure on how to perform all of them on AE. It is new to me and there is not a whole ton of resource material with it.
Are all the tests you mentioned Key on Engine Off? (Just so I don't get it wrong) I can understand issues after the delete... But to have it work so well for a week and then to act up... Seems weird. Looks like my mpg MAY now be dropping a little also..but after just a quarter tank I am not sure as of yet. Need to burn more to get a better average.
Power band testing showed all cylinders pulling their own weight equally... So if I am correct in my thinking if I had a bad injector it would show up on the graph on AE. So I think an injector issue is not the cause. I did check for exhaust leaks and have not found any... (One of my first thoughts for low boost was a exhaust leak before the turbo and I check that)
Pcm relearn... Going to have to research the process on that. Not entirely sure of the process of that.
I would ask is it a bad move to order a upgraded cac tube bit the more i think about it... Even if that's not the issue it's better to get rid of the plastic crap tube anyway.
Thanks
You are absolutely correct about the 25-28 psi from the factory. I'd shoot for the best numbers the truck can deliver.
AutoEnginuity is garbage --- old interface (Windows), clunky, laptop based with little support (a couple of knuckleheads minding the phones in Arizona)......I dumped it it favor of other OEM and after-markets scanners.
Baseline PIDS are done OFF. The rest get modulated at different RPMs.
CAC upgrade is definitely worth it.
#11
09-19-2016, 07:09 PM
update
Ok... so I did the CAC upgrade to the metal tube.. all hot side boots look great.. no rips.. tears... leaks etc.
I took it for a drive tonight after doing the upgrade and I am still at the same spot I was with boost. Have not gained anything (agh...) I was really hoping for a leak on the cold side that this would fix.
Anyway... Not sure where to go next. I am thinking about removing the turbo and intake manifold again this weekend to make sure everything is aligned properly. (This way I can also get to the down tube and make sure that is aligned properly also and nothing shifted while I assembled it)
As stated before, I do have AE with the ford package and nothing is coming up as an issue with it. Others have mentioned that i need to find my baseline PIDs.. Look.. to be completely honest, I do not have any idea on how to do this with AE. (If someone is familiar with AE PLEASE help me!!!)
I have heard recently that AE is not the greatest program out there... but, its what I have to use...so I need to make the best of it. I just wish there was more tutorials on how to use it. (hey we all started out somewhere once)
So, to recap, slight lack of power... turbo boost is only at like 19psi (max 20-21 psi at its highest..and only briefly) used to be at 25-28 psi, then I did an EGR delete and lost the boost pressure down to 20-21 and lost some power.
Anyone out there than can help me, it would be appreciated. I have to do some hauling soon I really need to make sure that it will be ok as I do not want to be broke down with 3-4 tons of coal on the truck.
Oh and one more thing I need to mention... when everyone says boost pressure is at XX amount at WOT... For me at WOT (like on a highway) my boost will drop out once I get to a certain speed. It used to be a state truck, so I am not sure if there is a speed limiter on it but 85mph is the max speed I can get from this truck.. If I am accelerating to 85 mph.. the boost is up at (again... somewhere between 19-21) once i get up to speed it drops down to like .. 10psi or lower... it will come back up if I accelerate again but is this normal for anyone else?
I need to avoid a large bill from a shop but I am getting to the point that I may not have a choice as I soon need to figure this out. (and being a mechanic of industrial machinery, NONE of this work is out of my realm... I just dont know where to go to next - and this will personally be a failure to me if I don't fix it and someone else needs to)
Thanks,
-wyatte
I took it for a drive tonight after doing the upgrade and I am still at the same spot I was with boost. Have not gained anything (agh...) I was really hoping for a leak on the cold side that this would fix.
Anyway... Not sure where to go next. I am thinking about removing the turbo and intake manifold again this weekend to make sure everything is aligned properly. (This way I can also get to the down tube and make sure that is aligned properly also and nothing shifted while I assembled it)
As stated before, I do have AE with the ford package and nothing is coming up as an issue with it. Others have mentioned that i need to find my baseline PIDs.. Look.. to be completely honest, I do not have any idea on how to do this with AE. (If someone is familiar with AE PLEASE help me!!!)
I have heard recently that AE is not the greatest program out there... but, its what I have to use...so I need to make the best of it. I just wish there was more tutorials on how to use it. (hey we all started out somewhere once)
So, to recap, slight lack of power... turbo boost is only at like 19psi (max 20-21 psi at its highest..and only briefly) used to be at 25-28 psi, then I did an EGR delete and lost the boost pressure down to 20-21 and lost some power.
Anyone out there than can help me, it would be appreciated. I have to do some hauling soon I really need to make sure that it will be ok as I do not want to be broke down with 3-4 tons of coal on the truck.
Oh and one more thing I need to mention... when everyone says boost pressure is at XX amount at WOT... For me at WOT (like on a highway) my boost will drop out once I get to a certain speed. It used to be a state truck, so I am not sure if there is a speed limiter on it but 85mph is the max speed I can get from this truck.. If I am accelerating to 85 mph.. the boost is up at (again... somewhere between 19-21) once i get up to speed it drops down to like .. 10psi or lower... it will come back up if I accelerate again but is this normal for anyone else?
I need to avoid a large bill from a shop but I am getting to the point that I may not have a choice as I soon need to figure this out. (and being a mechanic of industrial machinery, NONE of this work is out of my realm... I just dont know where to go to next - and this will personally be a failure to me if I don't fix it and someone else needs to)
Thanks,
-wyatte
#12
09-19-2016, 08:58 PM
Long shot old school option for up-pipe leaks if you can't get the pipes aligned:
https://www.ford-trucks.com/forums/1...ml#post9811394
Another longshot is AE doesn't do uncompensated contribution tests, certain FICM flashes can do a lot of covering for a bad injector, like entirely hiding one failed stick. AS I understand it only the real-deal IDS can do the uncompensated test. It might be worth a call to a dealer to see if a tech will run that one particular test for an hour of shop time.
Good read about FICM flashes and the inductive heating flash covering for failed injectors (up to 3+), meaning you might have had one or two dropping and now that a third is bad performance is dropping:
https://www.ford-trucks.com/forums/1...l#post16585483
IIRC the factory limit for OEM 17s was 87mph. It took an SCT tuner for me to go over 90. Dashboard speedometer is off by a needle-width at multiple places versus a digital speedo on my truck, so your 85mph is probably you hitting the limiter.
https://www.ford-trucks.com/forums/1...ml#post9811394
Another longshot is AE doesn't do uncompensated contribution tests, certain FICM flashes can do a lot of covering for a bad injector, like entirely hiding one failed stick. AS I understand it only the real-deal IDS can do the uncompensated test. It might be worth a call to a dealer to see if a tech will run that one particular test for an hour of shop time.
Good read about FICM flashes and the inductive heating flash covering for failed injectors (up to 3+), meaning you might have had one or two dropping and now that a third is bad performance is dropping:
https://www.ford-trucks.com/forums/1...l#post16585483
IIRC the factory limit for OEM 17s was 87mph. It took an SCT tuner for me to go over 90. Dashboard speedometer is off by a needle-width at multiple places versus a digital speedo on my truck, so your 85mph is probably you hitting the limiter.
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