Medium and Heavy Trucks

Have truck repair questions? Ask an Expert

Connect one-on-one with {0} who will answer your question

This answer was rated:

I have a 2003 mack MR truck. 2003 Mack Mr truck E-7 engine.

I have a 2003...

I have a 2003 mack MR truck

Mechanic's Assistant: What specific product are you working with?

2003 Mack Mr truck E-7 engine. Problem with truck stumbling some. Inactive code keeps coming up no 3 eup. and data link. Active code is fan clutch output which I assume wouldn't cause truck not to take fuel at Times and then pkup again. I have replaced number 3 eup and injector nozzle. Also replaced transfer pump and cam sensor. Wiring seems good. 4 volts going to every eup and pulse is the same on every eup. Haven't programmed rip but was told rarely that is a problem and I have swapped eup before never a problem. I have. Good software that trouble shoots coded and solutions. At a loss. Have own macks. 30 yrs.

Mechanic's Assistant: How long has this been going on with your computer? What have you tried so far?

All of the above

Mechanic's Assistant: Anything else you want the Computer Expert to know before I connect you?

No. Just a Mack truck mechanic

Show More
Show Less
Ask Your Own Medium and Heavy Trucks Question
Answered in 3 hours by:
6/22/2020
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 2 years ago
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,479
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified

Hello and Thank you for using Just Answer. My name is ***** ***** I'd like to try and help. I am sorry that you are having issues with your truck. I know this can be frustrating. Please allow me a few moments to look over your question and I will be right back with you. Thanks

Ask Your Own Medium and Heavy Trucks Question
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 2 years ago

Pin 42-23 are the pins on this circuit. The EUP's share a common for the front and the rear banks. If you have anyone of the EUP's short out it can wipe out the bank or it will signify a misfire on that one cylinder. I would check the wire end to end and perform a wiggle test on the engine harness itself. I would also pull the eup roller and see if you have a flat spot on it. I have had these where the roller will have a flat spot and will catch and roll back to a good spot where it can fire again. Once the EUP is out they pull right out to check them. I would also plumb a gauge into the pump outlet fitting and measure it while driving to see if you have any dump in pressure when this is under a load. The trim code will not affect this like your complaint. It can cause an issue under load but I have never experienced that. I believe the trims are used more for tracking purposes than anything. The fan clutch code is an isolated fault which is on a circuit itself, though it is controlled by a driver. Which the EUP's are as well. I would see about an test ECM on this one and give that a try as well. I hope this helps. Please let me know if you have any further questions on this. Thank you.

Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,479
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified
Mike Mcmillan and 87 other Medium and Heavy Trucks Specialists are ready to help you
Ask your own question now
Customer reply replied 2 years ago
Think I am going to swap ecu and wiring
Same yr, engine, and set up on trash truck which was known to be good. Tried wiggle Wires but no diff in engine idle. Has data link inactive code also
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a technicianLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Mike Mcmillan Your Own Question
Mike Mcmillan
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,479
6,479 Satisfied Customers
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel

Mike Mcmillan is online now

Related Medium and Heavy Trucks Questions
This is a second question for a truck you helped out with
Hello this is a second question for a truck you helped out with last week . 2004 mack cv713 with a ai 427 getting a code for #5 sid 5 FMI 8 code . Did a cylinder shut down , and #3 and #4 do not sound… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
Injector cylinder #4 9 times 02/01/21 10:47:31 pm injector 4
Injector cylinder #4 9 times 02/01/21 10:47:31 pm injector 4 Abnormal frequency pulse width or period … read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
I have a 2003 Mack Mr Inactive data link code 1587 keeps
I have a 2003 Mack Mr Inactive data link code 1587 keeps coming up. Truck not taking fuel as it should, hesitates then will pkup speed and smooth out with slight surge back and forth. I have the diagr… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
I have data link code coming up on 2003 Mack MR. VECU
I have data link code coming up on 2003 Mack MR. VECU 1708/1587 Tried and replaced ECM, vecu. Checked grounds, shook wiring every where. No impactStumbles some under strain and smokes occasionally fro… read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
Have 2003 Mack Mr Have vmac 111 dealer level por link
Have 2003 Mack Mr Have vmac 111 dealer level por link scanner. I have several inactive codes that have zero counts. What does this mean? I generally check trouble codes with key on engine off. Should … read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
I have 2003 Mack Mr E tech that trouble codes are coming up
I have 2003 Mack Mr E tech that trouble codes are coming up inactive with zero count. Fan clutch low output but fan clutch is viscous type manual with no wires or airlines connected to it or anything … read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
I have a 2003 Mack Mr truck E tech engine. Do the fuel
I have a 2003 Mack Mr truck E tech engine. Do the fuel injector nozzles require both top and middle o rings? Been told yes and no.… read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
Have 2003 mack truck. Mr model. Truck surges and misses
Have 2003 mack truck. Mr model. Truck surges and misses under heavy load at times and at 3rd or 4th shift consistently. Vmac3 scanner says sid 250 data link problem. Replaced ecm wire harness. No chan… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
I have 2003 mack Mr trash truck Problem with truck surging
I have 2003 mack Mr trash truck Problem with truck surging and loosing power,stumbling going up hills under strain. Tried a lot- replaced no.3 rip and no.3 nozzle injector came up on scanner.installed… read more
JimmyM827
JimmyM827
Bobcat specialist
Automotive technologies
70 satisfied customers
Have a 2003 Mack Mr trash truck I have installed. No 3. New
Have a 2003 Mack Mr trash truck I have installed. No 3. New eup. Different answers on should cal code be program. I have vmac111 software scanner so I can program. But does it impact performance if I … read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
I have a 2007 mack MR trash truck E 7 My question is some
I have a 2007 mack MR trash truck E 7 My question is some one wired the rev up switch toggle directly to ecm or VECU. The rev up toggle should shoot electricity to sensor that is iniated by handle On … read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
Have a 2003 mack with a ami 370 and keep getting a code for
have a 2003 mack with a ami 370 and keep getting a code for injector 3 so replaced and took for a test run and still came back with a code for injector 3 what do i need to check for next… read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
I have 2003 mack Mr. Vmac3 system. 6 EUPs. 2 questions.
I have 2003 mack Mr. Vmac3 system. 6 EUPs. 2 questions. Laptop code came up no.3 euro. Swapped eup from another truck same year and engine. Ran better but stumbles at Times taking off. Do the eups hav… read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
I have 2003 Mack Mr truck and truck missing randomly. I have
I have 2003 Mack Mr truck and truck missing randomly … read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
I have a 2006 chn 613 with an aset will not start. # 6 eup
I have a 2006 chn 613 with an aset will not start. # 6 eup bolts broke engine stopped replaced Orings and bolts. I have fmi 4 inactive code on all 6 eup … read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
06 Mack cv713... vin ***************** I HAD 2 INACTIVE
06 Mack cv713... vin ***************** I HAD 2 INACTIVE CODES... one was low coolant... filled cleared; ok My other tech said it had the lightening bolt light on... I started and ran, no light... I ha… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
6,062 satisfied customers
I have 2001 Mr Mack trash truck Low power and ticking like
I have 2001 Mr Mack trash truck Low power and ticking like valve sound especially pulling a hill. Replace ecu because Injectors only getting one volt to all six injectors Still have same problem after… read more
Mike Mcmillan
Mike Mcmillan
Shop Foreman/Triage Tech
Associates
6,479 satisfied customers
I am getting no voltage to the eups, I melted some
I am getting no voltage to the eups, I melted some wiring 8 month ago and a service tech rewired the front 3 cylinders. Been running fine since. I parked it for two days tried to start it, it acted li… read more
Diesel fumes
Diesel fumes
8 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Daniel Wilson

Daniel Wilson

6,062 satisfied customers

Owner at DJ Wilson

Cat Man

Cat Man

Cat Engine Expert

5,353 satisfied customers

I am ASE Master Truck Certified.

Wayne

Wayne

Journeyman

5,115 satisfied customers

worked on, Gmc, Macks, Freight liner,Mercedes Benz,,Ford, sterling

Jeremy

Jeremy

Certified Truck/Bus Technician

2,756 satisfied customers

ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, Network Engineer specializing in CAN faults, Aftertertreatment, and vehicle communications

Curtis B.

Curtis B.

Technician

1,947 satisfied customers

Technician turned service manager on multiple lines of trucks and engines, used in industry.

cumminsdr

cumminsdr

Mechanic

1,886 satisfied customers

All types of Cummins applications

Chris (aka-Moose)

Chris (aka-Moose)

Technician

641 satisfied customers

24 years of experience diagnosing & repairing

< Previous | Next >

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x