Mustang Evolution Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
648 Posts
Discussion Starter #1
Thought fuel pump went out because i could not hear it prime so I checked the relay under the hood and it was good. I jumped the inertia switch in the trunk and it did nothing. I finally changed the pump and it still did not work. What am I missing? Any help would be appreciated.
 

·
Registered
Joined
·
648 Posts
Discussion Starter #3
93slowstang said:
It could be your ignition switch or possibly a fuse.
The ccrm is clicking when I turn the key to try and prime the FP. Could a relay click even if its gone bad?
 

·
Registered
Joined
·
6 Posts
i am having the same problem with my 94 gt, i put a brand new FP in, in June. I unpluges the wiring going to the puimp, so i am getting power to it. I checked all the relays, they are all good. Have to check if the connection to the fuel pump is bad, or if my pump just seized up.
 

·
Banned
Joined
·
8,779 Posts
The ccrm is clicking when I turn the key to try and prime the FP. Could a relay click even if its gone bad?
If it clicks once then stops, it is probably ok, but if it continues to click multiple times then the relay coil is failing and won't hold it on.
If your fuel line is already fully pressurized, you may not hear the pump run when the key is turned on. Does the car start and run at all?
 

·
Registered
Joined
·
648 Posts
Discussion Starter #7
Will not hit a lick. Checked to see if I had fuel pressure at my regulator and nothing came out. In the ccrm there are several relays so could it be one of the others clicking?
 

·
Banned
Joined
·
8,779 Posts
Will not hit a lick. Checked to see if I had fuel pressure at my regulator and nothing came out. In the ccrm there are several relays so could it be one of the others clicking?
Possibly, yes. Look in the Useful Info thread and in the Very Useful or Old Fuel Injection links you should be able to find a CCRM diagram that will help you identify the relays. It's handy to have for troubleshooting. :good:

Have you checked to see if you have power to the pump?
 

·
Registered
Joined
·
648 Posts
Discussion Starter #9
Trojan Horse said:
Possibly, yes. Look in the Useful Info thread and in the Very Useful or Old Fuel Injection links you should be able to find a CCRM diagram that will help you identify the relays. It's handy to have for troubleshooting. :good:

Have you checked to see if you have power to the pump?
No power to the fuel pump or the inertia switch. I did switch the ccrm out with a buddies good one but didn't solve my problem. Have 12v going to the 20A fuse in the engine compartment. Not real sure how to test if I have power coming out of the ccrm.
 

·
Banned
Joined
·
8,779 Posts
No power to the fuel pump or the inertia switch. I did switch the ccrm out with a buddies good one but didn't solve my problem. Have 12v going to the 20A fuse in the engine compartment. Not real sure how to test if I have power coming out of the ccrm.
Use a diagram to figure out which relay it is in the CCRM and which wires you need to test. :good:
 

·
Registered
Joined
·
648 Posts
Discussion Starter #11
Trojan Horse said:
Use a diagram to figure out which relay it is in the CCRM and which wires you need to test. :good:
I connected the right port of my data link connector(Behind passenger shock tower) to ground which should've made my pump run continually but it didn't. What does this mean?
 

·
Registered
Joined
·
648 Posts
Discussion Starter #12
Trojan Horse said:
Use a diagram to figure out which relay it is in the CCRM and which wires you need to test. :good:
Fuel pump relay diagnostics:
First, always check the inertia switch in the trunk and the fuel pump fuse in the underhood fuse box (20 amps). Also check the ignition switch fuses. With the key turned to run and checking within the fuel pump prime-out period (a duration of 2-5 seconds after turning the key to run): Check CCRM pin 5 for accessory 12 volts. If you have it, the issue lies downstream. If not: Check CCRM Pin 11 for constant 12 volts. Check CCRM Pin 13 for accessory 12 volts. Check CCRM Pin 18 for a ground signal during the prime-out.

If this is all good, check the inertia switch (located in the driver side trunk, adjacent the tail light) and fuel pump electrical connector at the tank.

If I'm not getting 12v on pin 5 does that mean the problem is upstream? God, I hate electrical problems!
 

·
Registered
Joined
·
648 Posts
Discussion Starter #13
Just a follow up, I've located the problem. I was cleaning out the glovebox and apparently previous owner installed a FP shutoff switch in there. I hit the switch and never knew it. I had the whole car torn apart but traced it all the way to the switch. Thanks for your help.
 

·
Banned
Joined
·
8,779 Posts
Just a follow up, I've located the problem. I was cleaning out the glovebox and apparently previous owner installed a FP shutoff switch in there. I hit the switch and never knew it. I had the whole car torn apart but traced it all the way to the switch. Thanks for your help.
:eek: It would have been nice if he had told you that.
Anyways, glad you found your new "theft" protection switch and solved your problem. :good:
 
1 - 14 of 14 Posts
Top