How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask spankyjr1 Your Own Question

spankyjr1
spankyjr1, Journeyman
Category: Medium and Heavy Trucks
Satisfied Customers: 1849
Experience:  I worked on all types of equipment semis,forklifts,farm,ect.
65057319
Type Your Medium and Heavy Trucks Question Here...
spankyjr1 is online now
A new question is answered every 9 seconds

2006 Isuzu npr. idles only, no throttle response.

Customer Question

2006 Isuzu npr. idles only, no throttle response. There is no voltage showing on either of the 2 wires that go to the Suction Control Valve. What do I need to check and repair to get this truck fixed?
Submitted: 2 years ago.
Category: Medium and Heavy Trucks
Expert:  spankyjr1 replied 2 years ago.
Hi I will help with your problem Please do not rate until all your questions are answered that way you wont have to pay twice Use reply to expert link.
Good morning,there are several different configurations on the trucks,it depends on were they were built for like USA or Europe.
Do you have a throttle cable?
The suction control you are talking about is it next to throttle linkage?
And do you know what that code say's, so I don't have to look up?{I have a idea just need clarification on what set up you have}.
Give me as much info as you think is relevant so I can give you the best answer.
Customer: replied 2 years ago.
Hi, and thank you, that all sounds great.
There is no throttle cable. it is a drive by wire system. The suction control valve (also called fuel pressure regulator) is attached to the side of the injector pump. The p0091 code says "Fuel Pressure Regulator Solenoid circuit open or short to earth". If I had a wiring schematic I was thinking of cutting the wire were it comes out of the ECM and wire a new wire directly to the fuel pressure regulator to determine if the wire/fuse is bad. Or also possibly trying a new ECM also.
Expert:  spankyjr1 replied 2 years ago.
Ok it is open because you have no voltage, not shorted. So you need to find what wire out of ECM powers it up.
Cutting the wire from ECM won't do you any good,you still need the 5 volt ref.signal to the solenoid and signal return.
Let me see if I can find a wire diagram,I just wanted to know what you were calling what, I thought you meant maybe fast Idle solenoid.
Know I know how to communicate with you. Some times people I talk to know nothing about system so if I said 1 thing they would not have a clue what I was talking about,but will be easier with you, because you have knowledge about how things work.
The one that is on injection pump is the air fuel ratio control valve, the regulator is on the return line or return side of fuel rail.
Anyway recheck voltage at sensor,to ground,one wire at a time you should have 5 volts to one wire,if you don't then we need to check at ECM,also you can just OHM out wire from sensor to ecm and check it that way to verify if it is the ECM.
Also it is throttle by wire, check voltage at throttle sensor, on throttle pedal,you can also do a sweep test on the pedal potentiometer.

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
< Last | Next >
  • 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!!!! Alex Los 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. GP Hesperia, CA
  • I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, 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. Esther Woodstock, 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. Robin Elkton, 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. Diane Dallas, TX
 
 
 

Meet The Experts:

 
 
 
  • Dan

    Technician

    Satisfied Customers:

    278
    17+ yrs. shop and field experience with all major brands of heavy equipment and trucks - 1995 WyoTech graduate.
< Last | Next >
  • http://ww2.justanswer.com/uploads/HE/HeavyEquipmentTech/2012-2-10_24025_Dan2012.64x64.jpg Dan's Avatar

    Dan

    Technician

    Satisfied Customers:

    278
    17+ yrs. shop and field experience with all major brands of heavy equipment and trucks - 1995 WyoTech graduate.
  • http://ww2.justanswer.com/uploads/yellowman99/2010-03-20_033822_Marshall_Pete_Furr.jpg Cat Man's Avatar

    Cat Man

    Cat Engine Expert

    Satisfied Customers:

    888
    I am ASE Master Truck Certified.
  • http://ww2.justanswer.com/uploads/WT/wtolkson/2012-6-8_12723_JApicture2012.64x64.jpg Wayne's Avatar

    Wayne

    Journeyman

    Satisfied Customers:

    695
    worked on, Gmc, Macks, Freight liner,Mercedes Benz,,Ford, sterling
  • http://ww2.justanswer.com/uploads/cumminsdr/2010-7-20_204410_ja.jpg cumminsdr's Avatar

    cumminsdr

    Mechanic

    Satisfied Customers:

    421
    All types of Cummins applications
  • http://ww2.justanswer.com/uploads/JA/JACUSTOMERd4x72o2z/2012-2-19_18516_2012212192822DSC0922.64x64.JPG spankyjr1's Avatar

    spankyjr1

    Journeyman

    Satisfied Customers:

    393
    I worked on all types of equipment semis,forklifts,farm,ect.
  • http://ww2.justanswer.com/uploads/TE/TellNoL437/2012-8-10_3919_ProfilePicforJustAnswer.64x64.jpg Jeremy's Avatar

    Jeremy

    Truck/Bus Technician

    Satisfied Customers:

    176
    ASE Med/HD Truck Technician, NATEF, 608/609, Bendix, Haldex
  • http://ww2.justanswer.com/uploads/KO/koboma/2012-6-6_20917_DSCF1022.64x64.JPG Curtis B.'s Avatar

    Curtis B.

    Technician

    Satisfied Customers:

    148
    Technician turned service manager on multiple lines of trucks and engines, used in industry.