Medium and Heavy Trucks
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My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.
If you have not had the exhaust tested for excessive back pressure at all this should be done.If there is excessive back pressure this will cause this fault here and the restricted exhaust component would need replaced to correct this issue.I have seen exhaust filters as well as components like a catalytic converter restricted or even a muffler restricted limit the boost,engine power and vacuum and cause this issue here.If this was already tested and found o.k. let me know.
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In some cases low vacuum or issues with turbo boost can be caused by a fault with carbon build up in the engine usually in the intake ports as I have seen before.If this has not been checked this should be done to see if any issues are found needing corrected.
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Unfortunately I am unable to place a call on this here myself.If you would like I can open your question up for others here to see if anyone else can assist further on this just let me know if this is something you would like to do.
I apologize.I posted as I saw no one else had and wanted to help in any way I could since there was no other response.
I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.
Hello there! Thank you for choosing Just Answer, I am happy to assist you with your question today. Can you please provide the 8 digit engine serial number for your motor? This way I can pull up specific specs for you.
Have you been able to resolve your question? If I can be of assistance please let me know! Thank you
Thank you for the esn, when I read your question initially the first component that came to mind was the intake manifold pressure sensor, these can plug up causing low boost. Have you checked this sensor? I have attached a couple different t/s trees (I know you mentioned there were no codes but I am basing your information on codes I have seen before to obtain the t/s info for you) As you know it is difficult to diagnose over the internet so I am starting from scratch to try to get you to your result. Some of the t/s trees have info that does not pertain to your engine if you have since deleted the egr, please disregard those areas and keep to the rest. Please let me know any questions or how you would like to proceed. I hope I have been able to at least get going in the right direction! Also just as an fyi I see the ecm calibration for this engine is AB10342 (or was last recorded as) The current ecm calibration for this engine should be: AB10342.23. There are two revisions under this calibration that pertain to boost. This could very well be your issue if the ecm calibration is not up to date
I am not seeing all of the links I added to this. If I sent them multiple times I apologize. if you only received one please let me know.
Ok no problem, just wanted to begin with that because I have seen it many times in the field. Have you updated the ecm calibration recently?
My concern remains with the intake manifold pressure sensor. If the EGR was deleted this could easily confuse the system to read incorrectly and thus you would have a boost problem without any fault codes. Did the issue begin after deleting the EGR?