SPONSORED LINKS

Engine not starting

Tiny
GOOBERSTOYOU
  • MEMBER
  • 1999 PONTIAC GRAND AM
  • 108,000 MILES
My 1999 pontiac grand am with 2.4l engine has spec fuel pressure spark compresion runs with carb spray but doesnt have a injector pulse both wires to injectors have constant power
Monday, June 27th, 2011 AT 5:34 AM

11 Replies

Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
You're seeing power to both wires because you are testing it with the injector connected. It's the ground pulse that you are lacking. See if you have lost spark also to indicate a problem with the crank sensor. If not, check all your fuses and power supplies to the PCM.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
GOOBERSTOYOU
  • MEMBER
  • 7 POSTS
I have spark for sure I can run the car with starting fluid I have fuel pressure but you can take a test light to the injectors and they do not pulsate and you can use a stethoscope on the injector itself and it is not clicking I am testing this while car is running with starting fluid and there's nothing at crank or at running.

What sends signal to the injectors?
Was this
answer
helpful?
Yes
No
+3
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Could be one of these the cam and crank sensor-sounds more like the injectors quad driver is fried meaning new brain box if wires checks out-
Was this
answer
helpful?
Yes
No
-1
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
GOOBERSTOYOU
  • MEMBER
  • 7 POSTS
Ok but the question is does the ignition module feed the injectors or something else
Was this
answer
helpful?
Yes
No
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
Test light? I hope your not testing injector pulse with a test light. That's a good way to take out the computer. You need to use a noid light or computer save diode light. I get the impression that you're looking for pulsing power to the injectors. You won't find that. They get constant power and pulsing ground from the PCM.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
GOOBERSTOYOU
  • MEMBER
  • 7 POSTS
Ok so I hooked up a noid light there is still no pulse I have listened to the injector no clicking for sure not getting signal I put in a new crank sensor and I had icm checked and its working so would brain box be my next choice or is there a cheaper solution
Was this
answer
helpful?
Yes
No
+1
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
Do you have power to one side of the injectors with the key on?
Was this
answer
helpful?
Yes
No
+3
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
GOOBERSTOYOU
  • MEMBER
  • 7 POSTS
Yes there is
Was this
answer
helpful?
Yes
No
+2
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
That's tentatively point to a bad computer but will require further testing.
Was this
answer
helpful?
Yes
No
+1
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
GOOBERSTOYOU
  • MEMBER
  • 7 POSTS
Ok so I have conquered one problem to lead to my next problem I now have a injector pulse I have spark my new fuel pump is pumping way to much pressure though 90 psi at key on position 100 at run not right but it is getting fuel but car still does not run new parts that I have put on fuel pump fuel filter computer ignition module camshaft positioning sensor I do not know what is wrong with this car could all four fuel injectors be clogged remember car will run with starting fluid
Was this
answer
helpful?
Yes
No
+1
Wednesday, July 29th, 2020 AT 10:01 AM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
The only way you can have that much pressure is if the pressure regulator is bad.
Was this
answer
helpful?
Yes
No
Wednesday, July 29th, 2020 AT 10:01 AM

Please login or register to post a reply.

Related Engine Not Running Content

How to fix an engine that wont start
VIDEO
How to fix an engine that wont start
Instructional repair video
Engine Not Starting
GUIDE
Engine Not Starting
Over the past 20 years at 2CarPros we have identified the top problems that are easily fixed. This guide can save you a trip to the repair garage or calling a tow truck and...
VIEW MORE

Sponsored links