04 mustang intermittent starting problem
#1
04 mustang intermittent starting problem
Hi,
Once in a while, after the car has been warmed up, I'll go into a store and when I come back out and try to start it will crank for about 5 seconds before it does anything. The cranking sounds normal, not slow or anything at all. Once it catches, it will idle around 100-300 rpm for 3-5 seconds as if it's going to die, unless I give it some gas. My car only has 30k miles on it so what the hell?... :/
Fyi, my dad's 2011 GT does the same exact thing. So, Idk if it has anything to do with old parts, maybe its just something that is inherent with some fords?
Any ideas? Does anybody else have the same problem? Thank you!
Once in a while, after the car has been warmed up, I'll go into a store and when I come back out and try to start it will crank for about 5 seconds before it does anything. The cranking sounds normal, not slow or anything at all. Once it catches, it will idle around 100-300 rpm for 3-5 seconds as if it's going to die, unless I give it some gas. My car only has 30k miles on it so what the hell?... :/
Fyi, my dad's 2011 GT does the same exact thing. So, Idk if it has anything to do with old parts, maybe its just something that is inherent with some fords?
Any ideas? Does anybody else have the same problem? Thank you!
Last edited by brkro86; 06-20-2011 at 03:47 PM.
#4
It is a common issue, heat soak vapourises the fuel in the fuel rails and the start-up AFR goes lean.
There is a function in the tune named Cranking A/F Ratio that can maps ECT against AFR while starting the engine--this can be tweaked to make it less of a problem...
Here are the settings I run:
You can see that I enrichened the mix at 200°+ ECTs...
There is a function in the tune named Cranking A/F Ratio that can maps ECT against AFR while starting the engine--this can be tweaked to make it less of a problem...
Here are the settings I run:
You can see that I enrichened the mix at 200°+ ECTs...
#6
Nope, my car doesn't have that gauge. Wouldn't it crank for a long time on cold starts too then b/c the pressure isn't built? It only does it on warm starts (and it only happens once in a while as I mentioned), also I always wait a couple of seconds with the ignition on before starting for the fuel to build up a lil bit.
#7
Nope, my car doesn't have that gauge. Wouldn't it crank for a long time on cold starts too then b/c the pressure isn't built? It only does it on warm starts (and it only happens once in a while as I mentioned), also I always wait a couple of seconds with the ignition on before starting for the fuel to build up a lil bit.
#8
Nope, my car doesn't have that gauge. Wouldn't it crank for a long time on cold starts too then b/c the pressure isn't built? It only does it on warm starts (and it only happens once in a while as I mentioned), also I always wait a couple of seconds with the ignition on before starting for the fuel to build up a lil bit.
Telling the tune to make the cranking mix richer by lengthening the injector pulse. It is still partially vapourised fuel passing through the injector, but there is more of it.
My '03 did this quite a bit here in Florida before I altered the cranking AFR function. There was a narrow window of time during which it did not like to start, 4 to 7 minutes. If you started it again almost immediately, or 10 minutes later, there was no problem; but inside that window...
#9
Thanks cliffyk, that makes perfect sense. And sorry that I didn't respond to your first post, I actually didn't notice it until now.. I need to start going through the thread each time lol.
Also thanks prometheus for your help too. If this issue does get worse (past the limits that cliffyk mentioned) then I will suspect a fuel issue.
Also thanks prometheus for your help too. If this issue does get worse (past the limits that cliffyk mentioned) then I will suspect a fuel issue.