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 Vladgmru Your Own Question

Vladgmru
Vladgmru, Automotive Electrician
Category: Chevy
Satisfied Customers: 2519
Experience:  I've been working with American made cars since 1992.
12883947
Type Your Chevy Question Here...
Vladgmru is online now
A new question is answered every 9 seconds

I have a 1997 Chevy K1500 5.7L (gasoline). Tonight when I

Customer Question

I have a 1997 Chevy K1500 5.7L? (gasoline). Tonight when I was driving home it experianced a problem. No abnormal indications on the gages. No abnormal sounds. I swear it kinda hicuped and gradually slowed down. Almost like it was starved for fuel. I could let it sit for a few minutes and it would restart. Again no abnormal indications. Within another few minutes it would die again... Looking under the hood, I noticed nothing. Oil was good. There was condensation in the tailpipes which was clear with no strange smell like oil or coolant. No leaks underneath. Fuel filter was replaced two years ago. I'm thinking fuel pump? Then again I'm not a mech.
Submitted: 6 years ago.
Category: Chevy
Expert:  Vladgmru replied 6 years ago.
HelloCustomer
My name is Vladimir.
The situation you described could be a fuel pump issue.
The fuel injection system in your truck requires at least 55-60 PSI of fuel pressure.
To be sure that it is indeed the pump problem, fuel pressure must be checked with a special gauge.
You should check the fuel pump relay, it is located in the fuse/relay box under the hood.
Remove it and inspect its terminals for any burned mark.
These relays( and sockets) tend to burn since these fuel pumps draw high current ( about 8-9 Ampere).
Here is the relay location view:
graphic
Customer: replied 6 years ago.
The neighbors are going to think I'm nuts... lol


Okay, I have the relay with me. OMRON # XXXXX D00

Five pins total. Two on the diagram side, three on the non-diagram side. I'm looking at the set of three.

The the first pin on the left, as I look at the non-diagramed side, appears to have a burn mark. I can see a small dot of copper vs the silver coloring of the pin. and what appears to be the burn mark above it. The middle pin in this set of three also appears to have a burn mark however, it does not have the copper coloring like the other pin.

Expert:  Vladgmru replied 6 years ago.
Ok.
I suppose that these pins have nubmers. Isn't it?
The important pins are # XXXXX and #30, they should be clean without any heat damage.
Check the corresponding "female" terminals in the relay socket( fuse/relay box housing), if it damaged as well, you have to replace these "female" terminals or a new relay will burn too.
Customer: replied 6 years ago.
You are correct, we're looking at number 87a (left looking at from the non-diagramed side) and 87 (middle). I'll have to check the female terminals when it's daylight outside. (3 a.m. here).

85 87 87A
86      30

I'll get back to you as soon as I can. If I can find my meter is there an go/no-go for ohm readings?
Expert:  Vladgmru replied 6 years ago.
I think you don't need to use a multimeter.
#87 should have +12 power all time
#30 gets +12 power when relay's contacts close and it feeds the fuel pump
#86 is ground for the relay coil
#85 is the control circuit for the relay coil from the PCM ( Powertrain Control module).
If you jump #87 and #30 "female" pins, the fuel pump should operate.
Do not jump these pins if you are not 100% sure with numbers.
That seems to be a wrong pins legend.
85 87 87A
86 30
Here is the correct bottom relay view:
graphic
Customer: replied 6 years ago.

85 87 87a


86 30

D7105

OMRON 12172234 D00

I'm looking at the relay again. It is as I've laid it out above.

I tried to draw it out on Word but the image will not copy so you can see the drawing above.

Between 30 and 87a there is a diagonal connector line.

87 has three dashed lines and single connector coming down from pin 87

Between 85 and 86 there is a

|___________

| |

_|__ |

| | ______

| | | | < -- Diagonal line in this box from bottom left to upper right

|___| |_____|

| |

| |

|_________|

I'm check the fuse/relay box under the hood. By location I have the correct relay pulled. It is also the only five pin relay in the fuse/relay box.

I wonder if there was an upgrade to the relay or someone (prior owner) put a different one into the fuel pump relay slot.

Expert:  Vladgmru replied 6 years ago.
Hi!
What you are talking about, is a diagram printed on the relay body.
My picture( was given above) represents the relay terminal location.
Look directly into the relay's terminals and then on my picture.
Does it make sense?
Customer: replied 6 years ago.
lol Yes it does.

Now we're on the same page.

Happy Thanksgiving!

Expert:  Vladgmru replied 6 years ago.
Smile
So, I am waiting for your checking results.
Take note, that relay socket in the fuse/relay box has got a "mirror image" of terminal numeration.
Happy Thanksgiving!
Customer: replied 6 years ago.
Okay here's what I found out:

1. I drew out the diagram you sent, then held it up to a mirror...

2. Looking straight down on the socket for the relay the pin numbers come out like this according to the mirror 87 86 /|\ Front of vehicle
87a
85 30

3. I found 12.35 volts on pin 87 (driver's side front female) with key on or key off.

4. I used the Fluke meter leads to jump from 87 to 30 and did not hear any clicking or noise. (key on or off).

5. Just to make sure I then used a piece of electrical wire and jumped 87 to 30. I hear a click and then the whine of the fuel pump. (Key off)
Expert:  Vladgmru replied 6 years ago.
Thanks.
What about burnt sign on #30 or #87 female terminals?
1it is OK
2It is OK
3It is OK
4Your Fluke leads are not a jumper wire, unless you set up the Fluke for current (Amper)measurement .
5.It is Ok that the pump is running when you supply the power.
The question is, does the pump produce enough pressure? Only a fuel pressure gauge can tell.
I have forgotten to tell you about another problem place on these vehicles, it is a fuel pump module connector. One of two wires/pins( A grey +12, or a Black ground) might be burnt. Unfortunately, it is very hard to remove this connector without removing the fuel tank.
Vladgmru, Automotive Electrician
Category: Chevy
Satisfied Customers: 2519
Experience: I've been working with American made cars since 1992.
Vladgmru and 5 other Chevy Specialists are ready to help you
Customer: replied 6 years ago.
There are no signs of corrosion or being burnt on the female sides.

Looks like it's off to someone with more specialized tools. Smile

Thank you Vladimir. I have enjoyed this conversation and you teaching me
something.

Be blessed, if there is a way to do so I'll let you know what is found out.

EdXXX@XXXXXX.XXX
Expert:  Vladgmru replied 6 years ago.
Hi!
Thank you for the accept.
I am glad to be helpful and you are always welcome!
You can continue replying in this topic, but please do not post any private contact information ( such an E-mail ). We are not allowed to do so.
I am looking forward to hear from you.
Regards,
Customer: replied 6 years ago.
Opps, sorry, I didn't realize that.

Thank you very much for the assistance.

Ed

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 was having a terrible problem with the wheel bearings on my 98 Chevy Cavalier and I suspect that using this website saved me plenty of time and money. Todd L Rochester NY
< Last | Next >
  • I was having a terrible problem with the wheel bearings on my 98 Chevy Cavalier and I suspect that using this website saved me plenty of time and money. Todd L Rochester NY
  • 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
 
 
 

Meet The Experts:

 
 
 
  • Tim's Auto Repair

    mechanic

    Satisfied Customers:

    7641
    Have owned a repair shop for 25 yrs.
< Last | Next >
  • http://ww2.justanswer.com/uploads/TI/tim37857/2011-10-28_23053_S6301814.64x64.JPG Tim's Auto Repair's Avatar

    Tim's Auto Repair

    mechanic

    Satisfied Customers:

    7641
    Have owned a repair shop for 25 yrs.
  • http://ww2.justanswer.com/uploads/DT/dt69nova/2012-6-15_234154_pic1.64x64.jpg Dave Nova's Avatar

    Dave Nova

    Chevrolet Technician

    Satisfied Customers:

    6870
    ASE Master Certification. GM World Class Certification
  • http://ww2.justanswer.com/uploads/ggrote1/2009-06-27_031011_me.jpg Gary's Avatar

    Gary

    Chevy Technician

    Satisfied Customers:

    5404
    15 years GM master tech
  • http://ww2.justanswer.com/uploads/testedtuff/2009-09-26_170108_pictures.jpg John's Avatar

    John

    Master A.S.E Automotive technician

    Satisfied Customers:

    4071
    A.S.E MasterTechnician A1-A8 w/L1,38 years experience General Motors Master Technician
  • http://ww2.justanswer.com/uploads/RO/rodcuda/2011-7-25_224114_Donhoff1.64x64.JPG Neal's Avatar

    Neal

    Chevy Mechanic

    Satisfied Customers:

    2306
    Shop Owner and Mechanic on multiple makes.
  • http://ww2.justanswer.com/uploads/goodwrench9124/2008-11-09_220838_dscf0007.jpg goodwrench9124's Avatar

    goodwrench9124

    ASE Certified Technician

    Satisfied Customers:

    2041
    Ase Master Certified, GM Master Certified Tech. Awarded GM Top performer, Hybrid certified
  • http://ww2.justanswer.com/uploads/DR/drivefast1971/2012-1-12_172422_0009051tQKh.64x64.jpg Ron Z.'s Avatar

    Ron Z.

    - Chevy Tech -

    Satisfied Customers:

    1912
    18+yrs experience. State Inspector and Chevy Diagnostics
 
 
 
Chat Now With A Chevy Mechanic
Vladgmru
Vladgmru
Automotive Electrician
305 Satisfied Customers
I've been working with American made cars since 1992.