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 Ron Your Own Question
Ron
Ron, ASE Certified Technician
Category: Chevy
Satisfied Customers: 34125
Experience:  35 years experience with ASE Certs
7276279
Type Your Chevy Question Here...
Ron is online now
A new question is answered every 9 seconds

What tells a throttle body injector to fire?

Customer Question

What tells a throttle body injector to fire?
Submitted: 1 year ago.
Category: Chevy
Expert:  Ron replied 1 year ago.

Hello and thank you for you question,
The injectors are fired by the signal from the distributor pick up coil and ignition module to the PCM (computer) . What type of problem are you having?

Do you have spark to the spark plugs ?

Customer: replied 1 year ago.
The pick up coil is new but the injectors just quit firing. If you wait a little bit then the vehicle will start again. Can this be the ignition module going bad.
Expert:  Ron replied 1 year ago.

Are you loosing spark when it will not start?

Customer: replied 1 year ago.
No
Expert:  Ron replied 1 year ago.

If you not loosing spark then that means the ignition module is working, so are you just loosing injector pulse?

Customer: replied 1 year ago.
we just verified again. It will run for a minute then shut off, we can restart and it will run for 20 seconds then shut off again. When it dies the injectors quit spraying. We can restart and it runs for 10 seconds or so then shuts off again. The it won't restart unless you wait a little bit.
Customer: replied 1 year ago.
New fuel pump and fuel filter it is putting out 15lbs when it is on and 13 when vehicle is running
Expert:  Ron replied 1 year ago.

I would start first with checking to see if your getting the injector signal out of the ignition module to the ECM (computer) while the problem is occurring.. I have enclosed the steps in the link below, copy and paste the link to your browser to open and view them.

https://dl.dropboxusercontent.com/u/104923897/ECM%20test%20Nov%2013.pdf

Customer: replied 1 year ago.
I need this dumbed down a little. What is the doc and where is it.
Expert:  Ron replied 1 year ago.

What are you calling the doc, due you mean the data link connector?

Customer: replied 1 year ago.
spell check changed
Expert:  Ron replied 1 year ago.

The DCL is the date link connector located right under the dash , its the connector you connect your scan tool to to retrieve codes from the computer. Take a look under there just to the left of the steering column and you will see it.