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 Gary Your Own Question
Gary
Gary, Chevy Technician
Category: Chevy
Satisfied Customers: 16900
Experience:  15 years GM master tech
19513769
Type Your Chevy Question Here...
Gary is online now
A new question is answered every 9 seconds

94 camaro hard to start when it does it has a miss

Customer Question

94 camaro hard to start when it does it has a miss
Submitted: 2 years ago.
Category: Chevy
Expert:  Gary replied 2 years ago.

I am sorry for the long wait

when it is at idle it has a bad miss ?

Customer: replied 2 years ago.
Its hard to start. i can hold the gas pedal down then it will finally start. when it does it has a miss at idle and higher RPM
Expert:  Gary replied 2 years ago.

and there are NO vacuum leaks ?

how high is the RPM once it starts ?

are there any codes being set ?

did it do this since the engine was rebuilt or it ran after it was rebuilt good for a while ?

Customer: replied 2 years ago.
has done it sense rebuild, had a miss before rebuild but had blow head gasket
Expert:  Gary replied 2 years ago.

are there any vacuum leaks ?

did it do this before the rebuild ?

Customer: replied 2 years ago.
No vacuum leaks
1000 rpm when it starts
have not checked for codes yet
Expert:  Gary replied 2 years ago.

did it do this before the rebuild ?

at 1000 it is running bad correct ?

if so if you unplug one injector are a time will any you unplug NOT make a difference in the idle ?

Customer: replied 2 years ago.
I have not unplugged any injectors at a time was not suer I could do that
Expert:  Gary replied 2 years ago.

yes

at idle see if any you unplug do NOT make a difference in the idle

we are looking to see if we have any dead cylinders

if you unplug an injector that the cylinder IS working the idle will get worse

a cylinder NOT working the idle will not change at all

can you see if any cylinders are dead ?

Customer: replied 2 years ago.
Im new to these of cars
Expert:  Gary replied 2 years ago.

see if it has any dead cylinders first

Customer: replied 2 years ago.
ok I will try that
Expert:  Gary replied 2 years ago.

let me know

Customer: replied 2 years ago.
It does have new injectors in it
Expert:  Gary replied 2 years ago.

ok lets see if any cylinders are dead next

Customer: replied 2 years ago.
ok I will try that later or tomorrow and get back to you
Expert:  Gary replied 2 years ago.

sure thing

you can always get me back through this post anytime for free with any follow up anything with this question even after you rate us here at Justanswer !

Customer: replied 2 years ago.
Ok ill try that and get back to you probably tomorrow
Expert:  Gary replied 2 years ago.

sounds good

Customer: replied 2 years ago.
I checked the fuel pressureTurned there key on and it had 30LBS
Started it up and had 35 LBS
unplugged the regulator while running pressure went up to 40 LBSso im guessing that I need a new fuel pump
Expert:  Gary replied 2 years ago.

at idle unplugging the fuel injectors one at a time where there any dead cylinders ?

or all 8 made a difference when unplugged one at a time ?

Customer: replied 2 years ago.
FROM WHAT I READ THE FUEL PRESSURE SHOULD BE 41 -47 LBS OF PRESSURE IM GETTING 30
Expert:  Gary replied 2 years ago.

yes you are correct the spec is 41 - 47 ley ON engine OFF

if it is below that replace the fuel filter if it still below spec the fuel pump is bad

Customer: replied 2 years ago.
I replaced that and these are the readings that I get. Low pressure I'm told can cause a miss
Expert:  Gary replied 2 years ago.

yes low fuel pressure can cause a miss

but we have to find out if it is a specific cylinder misfiring or not

and we need you to unplug each injector like i said to see if there is one or two specific cylinders missing or dead or not

if all 8 you unplug one at a time make a difference in the idle then we know this issue is something that is effecting all 8 cylinders

we need to know this

Customer: replied 2 years ago.
Ok but I know from this test the fuel pump is bad so why would I not replace it
Expert:  Gary replied 2 years ago.

yes replace it and the fuel filter and see if the pressure gets back to spec then see how the engine runs

the pressure needs to be corrected to spec first

if the fuel pressure is back to spec and still does this then see if there is a specific cylinder or not missing

i have just seen this time and time again of a few cylinders with the valves adjusted too tight causing this kind of issue especially after a rebuild

i just want your car fixed

Customer: replied 2 years ago.
I made sure to adjust them all the same. How ever It had a miss before I pulled the motor to rebuild it. had the same hard start just off and on.
Expert:  Gary replied 2 years ago.

ok i understand

i assumed it did this only after the rebuild

ok correct that fuel pressure first and see with the pressure back to spec how it starts and runs

with fuel pressure to spec it should start and run good

Customer: replied 2 years ago.
ill let you know
Expert:  Gary replied 2 years ago.

sounds good

Expert:  Gary replied 2 years ago.
you can always get me back through this post for free anytime with any follow up with this question anytime even after you rate us here at Justanswer !