94 GT cold start takes a long time cranking. Help!

DeanS

Member
Nov 25, 2018
17
8
13
Florida
Hi all. I need some help figuring out this thing. Been playing with this for a very long time and can't find anything on the web.
VEH: 94 GT 5.0 HO Convertible Automatic.

Symptoms: When starting after car has been off for a while and completely cooled off it cranks the first time and doesn't want to fire. After trying a few times it begins to fire like it is lean or flooded. Finally it will catch and then run fine. After running a while it will start normally. When I say cold start I do not mean cold, I'm in Florida and cold right now is 90 degrees.

Things done: The fuel pump in tank kept dying so now I put on and external pump and pressure is always at 38 to 40 lbs. The ect has been checked and replaced. Plugs have been changed. There is spark while cranking and timing is set base at 12 to 14 btdc. Injectors have been tested on tester and cleaned. Injectors are firing when cranking (verified with oscilloscope while cranking and running. Battery is new and cranks very fast. Compression Is good and when running KOER tests it passes the cylinder tests with a 9 code. I will try to attach a video of it starting if I can. The video shows the fuel pressure is good.
I don't see anyway to attach a video mp4 file so I zipped it.

I am pulling hair out trying to figure this thing out. After it does start it runs fine.

Has anyone ever seen this happen?
Please help me!
 

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Last edited:
When the engine is cold:

Turn the Ignition switch to the [On] position but do not crank the car.
After 3 seconds turn the ignition [Off] then back to [On] for 3 seconds.
Repeat this one more time.

Now, crank the car and tell us what happens.