My 2005 GT is giving me some trouble. When I try to start it, it has to crank over for 3-4 seconds before it fires. And sometimes it just barely starts, then sorta bogs and stumbles for a couple of seconds before it evens out. It used to fire really quickly. The strange thing is that once I start it, if I shut it off and try to re-start, it fires instantly. But if I let it sit for a while, it gives me the hard start issue again.
I thought it was a fuel pump issue, but that doesn't seem to be the problem. (Side note: My stock fuel pump crapped out last year, and I replaced it with aftermarket junk. It works ok, but doesn't draw all the fuel from the passenger side tank, and I stall out with 70 miles until empty showing... but that is a separate issue). I pulled the rear seat, and even pulled the pump out, and it checks out. I've tried turning the key to run for a few seconds before trying to start, to prime the system, but that doesn't help. I've also replaced the fuel filter. Once it is running, there are no issues. I can redline it through the gears and it doesn't run out of fuel or spark.
It is strange that it is hard starting after sitting, but will immediately fire if I shut it off and restart it. Any thoughts? Fuel pressure sensor? Crank position sensor? That FPDM thing in the trunk?
Other possible related facts: 1) I just replaced the Mishimoto radiator. I had one in there and it started leaking, so they replaced it. Could I have damaged something taking it out? 2) I have an Edelbrock supercharger on it.
Thanks!
I thought it was a fuel pump issue, but that doesn't seem to be the problem. (Side note: My stock fuel pump crapped out last year, and I replaced it with aftermarket junk. It works ok, but doesn't draw all the fuel from the passenger side tank, and I stall out with 70 miles until empty showing... but that is a separate issue). I pulled the rear seat, and even pulled the pump out, and it checks out. I've tried turning the key to run for a few seconds before trying to start, to prime the system, but that doesn't help. I've also replaced the fuel filter. Once it is running, there are no issues. I can redline it through the gears and it doesn't run out of fuel or spark.
It is strange that it is hard starting after sitting, but will immediately fire if I shut it off and restart it. Any thoughts? Fuel pressure sensor? Crank position sensor? That FPDM thing in the trunk?
Other possible related facts: 1) I just replaced the Mishimoto radiator. I had one in there and it started leaking, so they replaced it. Could I have damaged something taking it out? 2) I have an Edelbrock supercharger on it.
Thanks!