Stumbling Starts
07-24-2014, 09:52 AM
#1
Member
Thread Starter
Stumbling Starts
Good morning, folks. I've been experiencing a nuisance issue with my truck lately, and was wondering as to who out there may have any insight as to what could be causing my issue.
My truck is a '08 Supercrew FX2 Sport.
Purchased with 70,xxx miles
Odometer now reads 115,xxx miles
Here is a list of all maintenance that has been performed by myself within the time that I've owned it.
VCT solenoids replaced (Ford Motorcraft part)
Cam Phasers replaced (Ford Motorcraft part)
FPDM replaced (Ford Motorcraft part)
Plugs replaced (none broken
)
Transmission serviced
Rear serviced
Fuel Filter regularly changed
Air Filter regularly cleaned (K&N High Flow Element)
Throttle Body and MAF regularly cleaned
Full cooling system drain, flush, fill with new thermostat
Oil changed every 3,000 miles with Mobil 1 and Mobil 1 filter
Brakes always changed when needed
I am psychotic when it comes to maintenance on my vehicles. I perform all work myself and I've worked on vehicles and machines for a great deal of my life, so nothing about our trucks is that complicated to me. But this issue I'm having lately has me a bit stumped, So I'm asking for the community's help on this one.
As most of you know, starting crank intervals are monitored and controlled by the PCM on later model F-150's. What that means, is that you don't need to hold the key in the start position to keep the starter cranking until the engine takes off under its own power. Simply bump the key into the start position, and the engine will crank on its own until it takes off. Within the past week, I've noticed that my engine likes to stumble, more so often than not, whilst starting. It will crank for longer intervals, or seem as if it's just about to take off, then as it's about to die...the starter keeps cranking until it does take off. I can't quite put my finger on what could be causing this issue. Is it improper spark delivery? Improper fuel pressure regulation? Perhaps a Crank Position Sensor that is starting to go out on me?
I should make note, that this truck is a tank and I've never had a CEL come on. She runs just as well as the day I bought her...and I don't have any issue with power and torque. My only issue is just with starting, not with how the truck runs. I would just like to hear some ideas as to what someone might thing this could be. Thanks, guys.
My truck is a '08 Supercrew FX2 Sport.
Purchased with 70,xxx miles
Odometer now reads 115,xxx miles
Here is a list of all maintenance that has been performed by myself within the time that I've owned it.
VCT solenoids replaced (Ford Motorcraft part)
Cam Phasers replaced (Ford Motorcraft part)
FPDM replaced (Ford Motorcraft part)
Plugs replaced (none broken
)Transmission serviced
Rear serviced
Fuel Filter regularly changed
Air Filter regularly cleaned (K&N High Flow Element)
Throttle Body and MAF regularly cleaned
Full cooling system drain, flush, fill with new thermostat
Oil changed every 3,000 miles with Mobil 1 and Mobil 1 filter
Brakes always changed when needed
I am psychotic when it comes to maintenance on my vehicles. I perform all work myself and I've worked on vehicles and machines for a great deal of my life, so nothing about our trucks is that complicated to me. But this issue I'm having lately has me a bit stumped, So I'm asking for the community's help on this one.
As most of you know, starting crank intervals are monitored and controlled by the PCM on later model F-150's. What that means, is that you don't need to hold the key in the start position to keep the starter cranking until the engine takes off under its own power. Simply bump the key into the start position, and the engine will crank on its own until it takes off. Within the past week, I've noticed that my engine likes to stumble, more so often than not, whilst starting. It will crank for longer intervals, or seem as if it's just about to take off, then as it's about to die...the starter keeps cranking until it does take off. I can't quite put my finger on what could be causing this issue. Is it improper spark delivery? Improper fuel pressure regulation? Perhaps a Crank Position Sensor that is starting to go out on me?
I should make note, that this truck is a tank and I've never had a CEL come on. She runs just as well as the day I bought her...and I don't have any issue with power and torque. My only issue is just with starting, not with how the truck runs. I would just like to hear some ideas as to what someone might thing this could be. Thanks, guys.
Last edited by JByrd825; 07-24-2014 at 09:55 AM.
