dv86

So a few weeks back I made a thread stating; I had replaced my fuel pump, fpdm, fuel filter, both cam position sensors and both vct solenoids (rough idle). Cranks but still doesn't start first thing in the morning. I can crank on it till the battery drains but doesn't start. Once the sun hits it for 30-60mins it starts right up and will continue to start all day. No check engine lights no security light problems. I've even taken it a Ford dealer and let it sit there for two weeks with no fix. They changed the pump I had already replaced say it was defective. Said it was my driver module so they even put there's on and same problem. $800 later and still at square one. They did say it might be my PCM but that's a $250 gamble. I'm at a loss so any and on tips or advice is appreciated? Oh and the truck only has 129k.

redfishtd

Need to pin down fuel or spark problem . When was your last plug change . The newest plug for the 5.4 is the sp546 the 515's were trouble . Has it got new boots on plugs, moisture will make bad boots short out spark, always put new boots on with a small amount of dielectric grease on ends . This engine very fussy about plugs if not correct it makes too many odd symptoms . Guys have even replaced transmissions when it was just misfires . You may need to get amazon spark tester on it when shes dead . sounds like moisture problem to me shorting out spark .
If you get spark circuit up to par then we need to look at fuel . The fpdm is the main failure point on rear axle . But not only that the gasket in the connector can roll and cause this ,I had to pull mine out and it's been fine now for years .
Heat can effect electrical connections, may cause loss of spark or injector power . Using a voltmeter on the cops and injectors look for 12vdc on one side of each as the pcm just pulses the grd . You can use a noid light to check for this also.
Fuel pressure is not easy to check, some guys rig a tester in filter line under drivers door or get an inline tester . When she sits overnight fuel pressure bleeds down and sensor on fuel rail calls for the fpdm to start pump . Cold fuel may effect sensor if she's bad .
I would also clean the throttle body and maf , that's good maint anyway .
Too many guesses at this point .

Ecobuilder

Since the FPDM was replaced, I'd recommend to unplug it, give the connector a blast of air if possible, and securely plug it back in until you hear a click.

If it's not making good contact, it will give you the crank/no start condition.

Daz73

Aside from suggestions mentioned in above posts, to me this sounds like a classic poor connection issue...if it was pressure, I would think that no matter what you do the issue would stay. some more tests may be needed to eliminate the bleed down thoughts.

• Spray Contact Cleaner in your connections if your pulling them apart and make sure there no "tarnish" on the pins
• Does it start at 2am in the morning?...this may indicate if it was a bleed down issue over time or purely temperature issue.
• I'd be interested if you have the same problem if the vehicle was kept undercover overnight
• Where is the sun shining...(on what part of the car)....is your bonnet up and engine in the sun?
• Will it start if you leave it until midday in the sun with out trying it fist thing in the morning?

I wouldn't think that 30 mins of sun would generate enough heat to the engine if the bonnet was down...but i could be wrong as here in Aus we don't get snow in Winter unless your high up in the snow resorts!
**side note my 07 F150 is from Canada...I found a AC power cable under the bonnet and wondered what the hell it was there for....it's for the block heater..... Even in Winter the coldest we get is -10deg C (14F)

dv86

​​​​​I've been working out of town a lot but when I am home I have tried starting it at all hours. If I leave it b in the morning and try Monday, no problems. I have checked as late as 11pm after it had sat since about 5 and wouldn't start. That's kinda why I only drive it when the sun's out/ warmer days. It sits in the driveways facing south with the garage in front, hood closed. When the sun does hit it it hits the cab more than the hood. I do plan on checking my cops and injectors this weekend. What I haven't done since I got it back from the dealer is pull the line at the filter on a no start cold morning to c if there's anything. Before when I did this it was dry. Hence y I replaced the fuel pump, fpdm, and filter. Would a common auto parts store have a mood light? I have a volt meter. On another thread I was reading it that it could be the connection/wiring with the crank position sensor or the sensor itself but I have no codes. I will check my pressure, coils, and injectors this weekend and get back with u.

Daz73

Thanks for the response, The giveaway there is the fact it starts no problems if its been in the sun for a few hours... (I took it "Monday" is "Midday"). This almost certainly eliminates the loss of pressure from sitting.
I suspect a connector that's having a hard time when its cold and going open circuit...hence no codes. Can you hear the fuel pump turn on when warm or cold? It should run for a brief period when the ignition is on.
Perhaps as already suggested check your FPDM connector. As crazy as this might sound, and if possible, heat up the connector with a Hair Dryer to see if it starts one morning...perhaps even the fuel pump connectors or the connectors along the side. If you can simulate the "warming' effect you can be pretty confident of finding and fixing the issue.
If the Cab is warming up, this may point to the culprit also...more heat in the cab...maybe you key is having an issue in the ignition when cold...Double check all your fuses that control the engine, also...give them a wiggle it may be a simple dirty fuse.

redfishtd

I would agree with DAZ on a few points ,I have used heat to check for electrical conn problems as well as freeze spray . The cab is the first thing to heat up due to the closed windows . So yes a bad connection anywhere in there may do it . Key here is there is a missing history fuel portion of this . So anything in the fuel electrical path would bear some looking at . A voltmeter would help to see what's missing during the cold as well as a fuel pressure tester . Some off this may be done first just by using a electric heater carefully in cab . Should not take long to see if it starts. Then another cold morning a heat gun on specific areas of cab . Circuit boards are famous for cracks and doing this . It is very hard for a shop to take the time over days to check for an intermittent like this . Plus they use a heated shop .
Cleaning all connectors is not a bad idea but you may clear the problem without pinpointing it so it can pop up again .
Fuel should take awhile to warm up but fuel rail may warm up faster with fuel bled down overnight . which can happen faster with a dripping injector .




As you can see the pcm relay controls the signal first , then to the fuel relay ,to inertia crash switch then to the fpdm . Note that these points are controlled by the 12vdc path but also the body grounds which are highly subject to corrosion . Especially the fpdm above the rear axle . Clean all these grounds .

dv86

Ok I took all your guys advice and when thru a whole slew of testing, cleaning and heating to no avail. I used a hairdryer and started in the cab heating the dash, steering column, and fuse box. After that I went under the hood and heated all electrical components I could think of. After that I heated the fuel pump connections and all wires leading to the fpdm. I went ahead and replaced the crank sensor just cuz it was a cheap part. I bought a multimeter and test the fpdm, inertia switch, swapped relays, and coils. I also bought a obd ll. I used a a whole can of sea foam direct injection into the throttle body(hot soak). I cleaned the throttle body and maf sensor. I'm leaning towards a fuel issue is because if I spray starting fluid into the intake it starts up but just dies off. It has had a new fuel pump I installed but the dealer said it had a bad check valve so they installed another. It has a new fpdm and filter. All of this has been done within the last month. Still doesn't want to start when it's cold in the morning. I've done nothing but read and read to try and figure this out. I'm thinking about installing a block heater. With Summer coming along I don't see the weather giving me problems. So now I'm prepping to install a cam phaser lockout kit with a new tune. I just would like to fix the cold start problem. Any other ideas or areas to look.

Ecobuilder

Try to shift into neutral(N) with the emergency brake on when it does this and see if it fires up.

Just another attempt to see what works or doesn't and eliminate possible cause.

Ecobuilder

Also, if you haven't done already, check condition of fuse #102 and relay #203.

LINK to diagram.