Why does the fuel injector fuse blow when I turn my key to start?

Tiny
MEGMOBILE
  • MEMBER
  • 1989 BUICK CENTURY
  • 85,000 MILES
'89 buick century wagon. Been broke-down for several months, now. It stall pulling into my yard and will not crank. When I turn the key towards the start or cranking position, the fuse in the inside fusebox, marked injectors, blows! Everytime. Any ideas?
Do you
have the same problem?
Yes
No
Tuesday, October 4th, 2011 AT 3:49 PM

11 Replies

Tiny
SATURNTECH9
  • EXPERT
You have something in the circuit over loading the fuse a short to ground injector etc. Try unpluging all the injectors and see if the fuse blows?If it doesnt blow then you narrowed it down to a injector. If it does blow I would start tracing the wires from the injectors down looking for a pinched or chaffed wire to ground somewhere. Let me know what you find when you disconnect the injectors and see if the fuse blows. Before you unplug the injectors look and see if any wires are touching ground. That way you know you didnt stop the fuse from blowing by moving the wire away from ground when you unplugged the injectors.
Was this
answer
helpful?
Yes
No
-1
Tuesday, October 4th, 2011 AT 4:18 PM
Tiny
MEGMOBILE
  • MEMBER
Okay. Thanks. I'll go give that a try and let you know the outcome.
Was this
answer
helpful?
Yes
No
-1
Tuesday, October 4th, 2011 AT 4:27 PM
Tiny
SATURNTECH9
  • EXPERT
Alright please keep me posted.
Was this
answer
helpful?
Yes
No
-1
Tuesday, October 4th, 2011 AT 4:55 PM
Tiny
MEGMOBILE
  • MEMBER
Okay, I unplugged all the injectors and turned the key. The first few times it didn't blow the fuse. I checked the injectors with my test light and one side of each lit up "ground". All were the same. Then (as I'm charging the battery) I tried to crank it again and the fuse blew everytime. So I was back where I started. I began to trace all the wires. Some with the switch on and some with the switch off. I cant seem to get the battery to turn the motor over, so I think now I am gonna try to see if the starter's pos and neg are run right and aren't touching anywhere. But that fuel injector fuse seems to be grounding out. I turned the fan on one time while I put in a fresh fuse and the fan died down right much. What about the re-call that buick had on the centurys, due to a failing "jumper-harness" going to the fuel tank? My vin # barely missed it!
Was this
answer
helpful?
Yes
No
Tuesday, October 4th, 2011 AT 6:22 PM
Tiny
SATURNTECH9
  • EXPERT
The injectors have a seperate fuse going to them then the fuel pump fuse has. With the key on one side of the injector harness should have a constant power and the other side is your ground pulse from the ecm. With a good fuse and the key in the run position see if one side has a constant power. It should be like a pink wire possible. The other wire to the injector shouldnt be a constant ground or the injectors would stay open all the time. Have your battery tested for the no crank also make sure your battery cables are clean and tight.
Was this
answer
helpful?
Yes
No
Tuesday, October 4th, 2011 AT 7:00 PM
Tiny
MEGMOBILE
  • MEMBER
Could that be from that harness going to the fuel tank? The reason that when I touched the test lite probe to the injectors while having it clamped to the pos. Side of the batt. That it lit up? Maybe the wires are grounded out further back? Did you find out anything on that "harness"? I am totally unaware of its location or anything dealing with it. You would think that Buick would have a diagram of that "re-called" part!
Was this
answer
helpful?
Yes
No
-1
Tuesday, October 4th, 2011 AT 8:02 PM
Tiny
SATURNTECH9
  • EXPERT
That jumper harness goes to the fuel tank which feeds the fuel sending unit and fuel pump different circuits the injectors. If the injector fuse blows while cranking makes me think the ground injector pulse from the ecm is shorted to the power side of the injector circuit. Because when you turn the key to the start position thats when the ecm sends out the ground pulse to open and close the injectors. So what color wire is showing the ground and what position is the key in. Also with the key in the run position which color wires has the constant power. Also dont try to check the ground pulse with your test light or you can damage the ecm. The ground pulse should only be tested with a noid light.
Was this
answer
helpful?
Yes
No
-1
Tuesday, October 4th, 2011 AT 8:39 PM
Tiny
MEGMOBILE
  • MEMBER
Okay so that jumper harness has nothing to do with this?
I will check the ecm next. I finally got hot on the pink wires on the injectors, constant power, with the key in the start position and jumping the battery with my Bronco. Thanks for the heads up on the noid light! I'll have to run down the wire for the ecm pulse ground. Now, I can't get the starter to turn over! It's been fine, now it's acting like it's locked up. You don't reckon that any starter or solenoid wire could have caused any of these malfunctions, do you? I'm still working on it and I want to thank you for your time and help! Let me know what you think and i'll keep on working on what you lead me to! By the way it's a 3300 motor (with the coil pack on the passenger side of the motor), most that I have seen have the coil pack in the rear of the motor.
Was this
answer
helpful?
Yes
No
-1
Tuesday, October 4th, 2011 AT 9:49 PM
Tiny
SATURNTECH9
  • EXPERT
No that fuel tank harness has nothing to do with the injector fuse blowing. As far as the starter solenoid wire that wire is power not ground. So does the starter make any noise when you turn the key to the start position?Have you had your battery tested to make sure you dont have a bad battery?Also did you make sure your battery cables are clean and tight?So does the other wire to the injector have a constant ground the non pink one?Also do you have a multimeter?
Was this
answer
helpful?
Yes
No
Tuesday, October 4th, 2011 AT 10:04 PM
Tiny
MEGMOBILE
  • MEMBER
I have a multimeter. Battery cables are clean & tight (put new ones on this morning). The other injector wire has a constant ground, as far as when I touch each one with the test light. I changed out the battery earlier, I felt that it may have had a bad cell. When I turn the key the starter sounds like it wants to, but just can't engage. I crossed (jumped-over) my solenoid and it would spin like crazy. If it ever tried to engage, the starter would kick in and stop it, dead in its tracks. But, when I just turn the key, it doesn't even try. I've got it up on ramps and jack stands, now. Of course, I had to use my jack to lift it up on the ramps. I just ran out of daylight, too. So, I'll have to get a jump on it again in the morning. Other than, maybe a new starter and solenoid, I'm welcoming any ideas that you have? Its been a long day. Thanks for all your help and God bless you. I'll be looking foward to what you'll have me doing in the morning, so please keep working with me on this and I'll keep you in the loop with any and all progress! I've got 3 more that I've gotta get running!
Was this
answer
helpful?
Yes
No
Tuesday, October 4th, 2011 AT 11:23 PM
Tiny
SATURNTECH9
  • EXPERT
Heres what I want you to test as far as the starter goes turn the key the start position and see if you have battery voltage to the small purple wire to the solenoid. Now for the injectors make sure the key is off unplug the ecm all the connectors going to it. Then see if there is still a constant ground to the non pink wire. Then pull the injector fuse then see any of the injector harness wires at each connector if those two wires in each connector are shorted to each other. By using a ohms meter on lowest scale settingLet me know your findings of what I asked you to test.
Was this
answer
helpful?
Yes
No
Tuesday, October 4th, 2011 AT 11:35 PM

Please login or register to post a reply.

Recommended Guides