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 Pete Your Own Question

Pete
Pete, Mechanic
Category: Car
Satisfied Customers: 15812
Experience:  15 years automotive training and experience.
14928985
Type Your Car Question Here...
Pete is online now
A new question is answered every 9 seconds

pickup isuzu: 1990 isuzu pickup 2.6lit 1ton this truck was

Customer Question

1990 isuzu pickup 2.6lit 1ton this truck was sitting fo five years i was abel to get it running but was missing at idle a littel bit but ran fine on hwy so i cleaned the gas tank out put new fuel filter i put rotor distributer cap and plugs i also puled off the throttle body cleaned it out with carb spray ceaned out the common chamber tested and cleaned 4 injectors tested mass air flow senser i put it all back together and now it lacks power also when im driving down the road at times i press the accelerator it will give a slite back fire and turn off the engen it wont turn back on untill i turn the key to crank the engen i also checked the fuel reg and i have 35 to 45 psi to the injectors also checed compresson 1=149 2=130 3=150 4=150 now engine misses throughout driving speed range can not drive it till i can get this repaired please can you halp me. Art
Submitted: 1 year ago.
Category: Car
Expert:  Pete replied 1 year ago.

HI Art,

My name is XXXXX XXXXX I am a professional here at Just Answer. I noticed that your question was not getting a response and thought I would see if you still need help with this.

Can you tell me how you had cleaned the fuel injectors on this vehicle?

Let me know so we can continue,thanks Pete.

Customer: replied 1 year ago.

I sprayed carb cleaner ineach individual injector with 45lbs of preasure behind it. used a AAA battery to have injector function.

Expert:  Pete replied 1 year ago.
Have you checked for any vacuum leaks before or after these repairs were done?
Customer: replied 1 year ago.


yes i went through it thouroughly. I used a spray bottle wth 90% rubbing alcohol. sprayed engine didnt hear RMP rise.

Customer: replied 1 year ago.

how can i check if the voltage is making injectors respond?

Expert:  Pete replied 1 year ago.
You can use a test light or a noid light to test the signal to each injector.To do this unplug an electrical connector from an injector.You should have battery voltage on one of the wires with the key on,the other wire is a ground pulse signal from the computer.You can crank over the engine and the noid light or test light should blink connected between these two wires at each injector one at a time.The test light may be dim which is normal when testing these.

Since the condition had got worse when the injectors were cleaned I am wondering if when you jumped power and ground to them if this damaged the injectors as I have seen this happen before and had to replace them.

Thanks Pete
Customer: replied 1 year ago.

I checked resistance on the injectors. I placed my own meter at 200 and the number 1 cylinder injector is at 4.9ohms, the number 2 cylinder injector is at 4.2 ohms, the number 3 cylinder injetor is at 5.3ohms, the number 4 cylinder injector is at 4.5ohms. Are these in spec? thank you

Expert:  Pete replied 1 year ago.
My chart shows the injectors resistance for each injector is between 2 and 3 ohms.Try this test with a cold engine if it wasn't done with a cold engine and see if the resistance is in range.If it still is not then these injectors may be at fault here causing this,may be due to jumping voltage to them and cleaning them and may need replaced.

Thanks Pete
Customer: replied 1 year ago.
Pete I have another test question on this truck how can I test the distributer I think there is no parts that I can interchange I think if it is bad I would need to change it out but I don't know how to test it thanks Art
Expert:  Pete replied 1 year ago.
Are you receiving spark on all cylinders?
Customer: replied 1 year ago.
Yes all cyclinders heve spark but I notice that the #1 and #4 was very light on the spark I did this I went one by one and started with #1 I pulled each spark plug wire and I placed a new spark plug in it and grounded it and nioticed the #1and #4 very lite spark I pulled out the distributar and cleaned it whith mass air flow cleaner I put it back together and spark is good but now driving down the road it has a bit of miss fire and when I step on accelerator it will have a small miss fire pop and turn engin off I turn key off and starts right back up. Thanks Art
Expert:  Pete replied 1 year ago.
If you have a timing light clamp it onto each spark plug wire one at a time and see if you can run the light into the cab with you and observe the light while driving (with a second person of course) and see if spark is cutting out on any of the wires when this occurs.If it is then most likely the distributor is at fault needing replaced here especially since when you cleaned it up it ran better this usually indicates this can be the issue needing corrected here.

Thanks Pete
Customer: replied 1 year ago.
I used a timing light on each plug wire and the # 1-2-and 4 looked like a normal pulse it was the #3 cylinder that was pulsing way to fast it almost looked like a flash light I can barely see a pulse it's to fast . I noticed when the engine cuts off when driving the spark is still firing , the engine is still turning key on engine off left in gear but when I turn the key off and crank the engine the engine turns back on Is it possible that the ECM turns off the injectors? Thanks Art
Expert:  Pete replied 1 year ago.
It is possible the computer or another sensor/component is causing the injectors to shut down.You would need to test the injector signals with a test or noid light when the problem occurs to see if this is the case here.
Customer: replied 1 year ago.
What can cause the #3 injector to fire so fast can it be a bad internal electrical components in the distributor?
Expert:  Pete replied 1 year ago.
Is #4 firing as fast as well or just #3?
Customer: replied 1 year ago.
Just #3 #1. 2. 4. Seems to fire normal thanks Art
Expert:  Pete replied 1 year ago.
O.k.,#3 and #4 both fire off of the same circuit from the computer (ECM) so most likely the ECM and wiring is o.k. as #4 would be affected as well if it wasn't.

The ECM relay provides battery voltage to the injectors which pass through a resistor before feeding the injectors.We know this cant be the pulse signal from the computer because #4 would be affected as well so this sounds to possibly be a fault with the resistor assembly for the fuel injectors possibly.I don't see the relay or wiring being a fault but if the resistor for the #3 injector is failing it may cause this here.

According to my info this resistor pack should be located on the passenger side fender assembly.Unfortunately I don't have any pictures of this to see this or to post here just a description of where it is located.It should have 4 black wires connected to it and one white wire with a yellow/blue wire plugging into the white wire.

I don't see this being an ecm at fault here and the only thing I can think of that may cause this since #4 and #3 are on the same circuit from the ecm is the resistor pack here.

Thanks Pete
Customer: replied 1 year ago.
Pete I'm sorry I meant to say the # 3 spark plug not injector I check the injectors with a light and a Macanic's thesis cope they seem to work right when I checked the #3 spark with the timing gun the pulse was to fast even at idle can this distributor have an internal electrical problem ? Thank Art
Expert:  Pete replied 1 year ago.
O.k.,if the cap or rotor has corrosion in it this corrosion can cause spark to jump to an area on the cap where it shouldn't and can cause this excess spark here,if you have not checked or replaced the cap and rotor this should be done,I have seen corrosion in the cap itself cause this here.I don't think this is the distributor itself as this would cause spark issues on all cylinders.

Thanks Pete
Customer: replied 1 year ago.
Yes I have put new plugs wires. Rotor Dis cap and coil
Expert:  Pete replied 1 year ago.
This is a difficult question to fully diagnose from here.I will opt out and put this question back on the list to see if others can assist more.Don't reply to my last post here unless it is a last resort as it will keep the question locked to me.I hope you can get this resolved with ease.

Thanks Pete
Expert:  Josie-Mod replied 1 year ago.
Hi, I’m Josie a moderator for this topic. It seems the professional has left this conversation. This happens occasionally, and it's usually because the professional thinks that someone else might be a better match for your question. I've been working hard to find a new professional to assist you right away, but sometimes finding the right professional can take a little longer than expected.

I was checking to see if you had already found your answer or if you still needing assistance from an other one of our professionals?

Please let me know if you wish to continue waiting or if you would like for us to close your question.

Also remember that JustAnswer has a multitude of categories to help you with all your needs from Pet to Legal.

Thank you,

Josie~Moderator
Customer: replied 1 year ago.
Yes still need help my truck still turns off when driving I accelerate and it dies can't figure it out it has a little misfire when beryl step on foot peddle Thanks Art
Expert:  Josie-Mod replied 1 year ago.
Hello

Thank you, we will continue to look for a professional to assist you. Please let me know if I can be of any further assistance while you wait.

Best,
Josie~Moderator

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:

 
 
 
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Last | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim Castleberry, FL
  • Excellent reply, and also very quick. Really sounds like the Expert knows what he is talking about. I will be back to use your service when I need more help with my RV. Dutch USA
 
 
 

Meet The Experts:

 
 
 
  • Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
< Last | Next >
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
  • http://ww2.justanswer.com/uploads/TE/TedG/2012-6-15_14759_avaLarge.64x64.jpg Ted G.'s Avatar

    Ted G.

    ASE Certified Technician

    Satisfied Customers:

    1596
    20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
  • http://ww2.justanswer.com/uploads/joecamel90/2008-11-13_03615_head_shot.jpg George H.'s Avatar

    George H.

    ASE Certified Technician

    Satisfied Customers:

    1311
    ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
  • http://ww2.justanswer.com/uploads/AM/amedee/2013-10-24_23656_Amedee1.64x64.jpg Amedee's Avatar

    Amedee

    ASE Master Tech

    Satisfied Customers:

    2367
    ASE Master Tech advanced level specialist
  • http://ww2.justanswer.com/uploads/SU/supermechanic/2013-8-23_03546_500.64x64.jpg Jerry's Avatar

    Jerry

    Master Mechanic

    Satisfied Customers:

    1906
    ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    942
    12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes
  • http://ww2.justanswer.com/uploads/ST/Steve7654/2012-6-5_215929_japic800x660.64x64.jpg Steve's Avatar

    Steve

    Auto Service Technician

    Satisfied Customers:

    1980
    25+ yrs experience as a professional working technician; ASE L1 master technician