2003- Starting issue after cars is not driven for a while

[Towny]

Hello all new here.

I have a 2003 Tbird, 21,000 miles. new COP's.
Battery went dead 2 years ago. Removed it and car sit for a year without a battery. This last winter I installed new battery and had all kinda of problems.
No dash lights etc. typical of the FEM. Sent it out to get repaired. Came back with problems solved only to uncover more..
Sent out REM to solve. Still uncover more issues, Sent out Gage Cluster to solve rest of issues and what do you know. Everything works..
Well not quite. More weird stuff happening..
Please watch the video in this link: https://*****************/6jLfUCiva9wDhn666
Recently started doing what you see in the video.
Start car runs for about 5 seconds then dies. Headlights come on then off. Security light on dash flashes some code then continuously.
Can’t just try to start car when it dies with key in the on position. Have to turn key to off then re-start then all repeats over and over about 4 - 5 times the it will start and run perfect..
So I've replaced all electronic modules except the ECM and powertrain module.

I've heard a lot about bad ground on the Tbirds??
Any advice as to which ground location could be causing the issue?? There's a lot of them.
I haven't checked to see if there were any codes set but will do so.
There were no codes set for any of the issues caused by the electronic moduals?

Thanks in advance, Towny

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[edward301]

I kind of get a feeling your ECM or PCM same thing has lost all of its driving characteristics that it stores from driving the car.
Once you get the car started without all of the strange occurrences, drive some, them come home and disconnect the battery
for no more than five minutes to reset. Then start car and see what happens. It is possible your ECM has lost some of its
programed memory, and might need to be reflashed, not sure but a good guess.

The fact that you have to turn the key off before trying to start again tells me the ECM is having to restart or reset.

Also two of my T Birds that sat for a while and would die after running for 5 or 10 seconds was a warning that my
fuel pump was going bad. After I replaced the fuel pumps, that never happened again.

Your alarm indicator on the dash is giving strange indications, will have to see what driving and resetting does.

 

[biddle]

Please watch the video in this link: https://*****************/6jLfUCiva9wDhn666
I've heard a lot about bad ground on the Tbirds??

1- Post your video on YouTube (owned by Google)
2- There's no bad grounding issue I've ever heard of in the 22 years I've managed this site.
3- Remember your car can have multiple problems and it appears you are troubleshooting one.

 

[Towny]

Hi and thanks a bunch for the reply.
I'll try what you've suggested and see what happens.
I did check for any set codes and nothing there.
This sounds crazy but the way my bird acts its like the electronics need to "warm up" to get functing properly??
Before I posted. I did take it for a 20 mile drive after it finally started and stayed running. Had no problems at all.
Stoped and turned car off to get some gas then restarted with no problems. It ran fantastic the entire time.
After it set for a couple days, went to start it and back to doing the same "no start" routine again. This is when I took the video.
The start / die timing is exactly the same each time I try to start the car. Start run a few seconds then die.
Can take 3 to 5 times of trying to start before it stays running.
May just send the ECM out and have it looked at. It's the last modual I haven't gotten repaired.

Thanks again.

 

[biddle]

After it set for a couple days, went to start it and back to doing the same "no start" routine again. This is when I took the video.
The start / die timing is exactly the same each time I try to start the car. Start run a few seconds then die.
Can take 3 to 5 times of trying to start before it stays running.

This is consistent with a failing fuel pump. Lots of failed fuel pump posted on the forums over the year, often times after the car sits and the problem can be intermittent