I'm having a hard start problem. Usually when cold it fires right up. But when warm, I have to turn it over for a a good 10 seconds before it finally catches. Any ideas?
The injectors may be leaking. Too much fuel gets into the cylinders just after you turn off a hot engine. After a while the fuel evaporates and starting is normal again. You can test for this by checking fuel pressure. It should stay up for a few minutes when the engine is turned off.
If your fuel pressure drops off quickly, they need cleaning. The best way is to remove them and send them to a pro cleaning service. You can also take the car to a repair shop that has some powerful stuff that they use for cleaning injectors. The least effective way is to add liquid injector cleaner to your fuel. You can buy it at Auto parts stores. It may take some time for this last method to work.
I had a similar issue, when you turn the key to the on position, do you hear your fuel pump prime? If not, check the relay behind the drivers window on the firewall. Mine starts immediately after finding out my relay wasn't working. Turns out after long cranking the oil pressure builds enough and the oil pump activates the fuel pump as a backup if the main relay has failed.
I have the exact problem you describe. Did you find a solution? I think I have to pull injectors out to find out if that is the problem. Hoping not problem. Anyways hope it is running better for you. Thanks
im in the same boat, i've been meaning to let the fuel pump prime for the full 2 seconds before i turn the ignition but keep forgetting my fuel rail has 45 psi, but it does leak down i think 5-10 minutes it lost 5 psi. and when i first hooked up to it it was at 0 so it leaks all the way out for sure. if you want to test things, you can buy a cheap switch to toggle the fuel pump test in your ALDL connector. or can one anymore? cause radio shack doesnt exist... i should take some of my own advice
my fuel rail has 45 psi, but it does leak down i think 5-10 minutes it lost 5 psi. and when i first hooked up to it it was at 0 so it leaks all the way out for sure.
This is perfectly normal. If your fuel pressure dropped to Zero in a few minutes - then there may be a problem. There is no check valve in the system, so the pressure normally dissipates back through the pump.
quote
Originally posted by thejimbud:
I had a similar issue, when you turn the key to the on position, do you hear your fuel pump prime? If not, check the relay behind the drivers window on the firewall. Mine starts immediately after finding out my relay wasn't working. Turns out after long cranking the oil pressure builds enough and the oil pump activates the fuel pump as a backup if the main relay has failed.
This is the most likely cause based on his symptoms. When oil is cold he has immediate high oil pressure. When oil is hot, it takes some cranking for it to build up pressure.
fierosound The pressure holds well at 42psi for at least 1/2 hour and slowly falls. I hear the relay click with ignition on fuel pump 2 sec run. Possible the relay is not working when hot or malfunctioning sometimes and I don't hear it? When I unplug vacuum line on fuel pressure regulator pressure increases. Which is good. Many people keep pointing to fuel injectors. Any ideas? Hate to rip it apart and the MONEY for injectors tested. Love the car but one thing after another.
fierosound The pressure holds well at 42psi for at least 1/2 hour and slowly falls. I hear the relay click with ignition on fuel pump 2 sec run. Possible the relay is not working when hot or malfunctioning sometimes and I don't hear it? When I unplug vacuum line on fuel pressure regulator pressure increases. Which is good. Many people keep pointing to fuel injectors. Any ideas? Hate to rip it apart and the MONEY for injectors tested. Love the car but one thing after another.
I'd say the problem is somewhere else, not with pump/relay etc. The Factory Service Manual points to possible ignition component problems.
[This message has been edited by fierosound (edited 07-14-2018).]
you do register rpm's when you are cranking right? mine just gave me issues where the rpm's were at 0 when turning over i went to the back touched the distributor cap, ground wires, and the tach filter, then it started cranking and fired up. completely different issue i suppose but mine also suffers from a hard start
That's pretty easy to check, hot or cold. Make sure you have spark that's able to jump 1/4" to exposed metal anywhere on the engine. If it does when cold, and not when hot, first component to suspect is the ICM.
Flood clear mode is still available to try when cranking. Excessive fuel in the combustion chamber is a possibility, so try starting with the gas pedal pressed to the floor. Free test, anyway!
I'm going to put a hair dryer on that icm to get it hot and see what happens. Its cold now and starts great when cold. I'll know if something is up if it cranks too long to start. I try clear flood and it still has problems firing up. Checked ohms on pickup coil and it was 835 so i guess that is ok. I have my bets on a fuel injector leaking after driving for awhile then sitting when hot. GOt to get this fixed!
I hope you are right fierosound. I don't want to take the plenum off and throw parts at it even though I am not sure (fuel injectors sent out and rebuilt etc). Wasted money. Don't have the time anyways. Want to focus on areas that I can test and rule out.
I guess you could say it it cranks strong when hot but takes 8-10 rough turnovers while trying to fire to idle. It starts on first fire when cold. Best I can describe it.
------------------ FIEROBUG!!!!!!!!!!
[This message has been edited by fierobug (edited 07-15-2018).]
My sons ‘88 Formula automatic does the exact thing. I have tried EVERYTHING and then some, except for replacing injectors. I did the injector bleed down/ fuel pump test. What I found was that the fuel pressure eventually goes completely away after a few hours. I’m not sure if that is normal or not. I need to subscribe to this thread...
.JPG)
It starts on first fire when cold. Best I can describe it. 
