1999 Pats,ground or what? Wmmburns?

MustangGTTJ

New Member
Feb 21, 2019
3
0
1
Kentucky
I only got on here because I haven’t been on forums for a long time and wmmburns you seem to be the mustang god.


Ok so this is a long post and I apologize ahead of time. I bought a 1999 mustang GT and I put everything from the heads up onto it. Every part came with the car but it has a 97 feel rail on it. It has 24 pound injectors aftermarket intake aftermarket Plenum and throttlebody. I got the car running after having the keys programmed for no reason because of ————- on the cluster and finding out that the PCM fuse was gone. I replaced the fuse in the car fired right up. Drove it down the road about five times. The car would starter so I change the mass air and it ran great. The only issue I was having was it acted like it wasn’t getting enough fuel but it wasn’t dying it would actually go pretty decent. I figured what the hell and I took it out to town. I got on it first second and third and then the car just kind of stuttered and died. After about 20 minutes the car fired right back up I drove it and put fuel in it premium to be exact in the car ran for another 30 minutes and has not stayed running since. I had it towed to my garage and the car would start an idle for about 1 to 2 minutes and then it would die. If you touch the throttle it would die instantly.

I thought OK my first gut instinct was to change the fuel pump. I noticed I wasn’t getting much pressure at the rail. I change out the fuel pump put everything back in place and the car was doing the same thing. A friend of mine came over today and he started pulling fuses including the PCM fuse and he jumped the inertia switch. The car now has ———— on the cluster again. I checked every fuse and I made sure that they were all good but I still cannot get the car out of theft mode. I left the battery cables off for hrs. I touched the two cables together to master reset it. I did find out that there is a ground issue to the fuel pump so I’m going to wire that up and fix it. Plug a scan tool from snap on and it communicated with the PCM. Checked my grounds on the motor and the front of the body. When I touch the connector with my tester the CCRM relays go nuts. I’m leaving the battery cables off all night and the key guy is coming back tomorrow to reprogram the car for free because maybe this time that’s what it needs. I know for a fact I have power to the PCM. What else could my issues be or what else can I check?
 
  • Sponsors (?)


IMO the solution to your problem is in your own words. "the CCRM goes crazy".

CONFIRM the PCM/CCRM ground around the radiator core support. Here's some information on the correct way to test grounds using the voltage drop method.

Howto perform charging system voltage drop test
https://www.stangnet.com/mustang-fo...perform-charging-system-voltage-drop-test.56/

If the CCRM relay is still "bouncing" STOP and find out why. Expect to have problems as long as the CCRM is not stable.

Test for key OFF power in and out of fuse F2.34, F2,2, and F2.8.

Repeat the tests with the key on. The key on values should be stable. Use a KNOWN good ground. Post the results.

This is also covered in the "crank with no start" check list.

1996+ Crank with no start check list
https://www.allfordmustangs.com/forums/4-6l-tech/336452-1997-mustang-wont-ignite.html
 
Last edited: