Cascade Special

My '96 F150 has always started flawlessly. Turn the key and it fires and starts immediately. That is until about a week ago. Now when it's stone cold it still starts like new but on subsequent starts I have to fully depress the accelerator while cranking and then it starts, runs rough for 10 seconds or so, then smooths out and runs fine. Other than that it runs fine, idles and accelerates and decelerates smoothly. Looking for some guidance. Is it a fuel pressure issue? Injector issue? Other electronic issue?

'96 F150 5.0L EFI automatic 2WD 285k miles.

Thanks for any suggestions.

CS

RobertFord

Very rough guess, but could it be a coolant leak into (one of) the cylinders? Would explain the hard start, and smooth out once it's running...

miguel.in.az

Might be a fuel pressure issue, rent a gauge from autozone and see what it read when you start it

Chris_1

iTrader: (1)

Checking fuel pressure hot and cold is a good idea. You should also check the codes, because a faulty sensor usually shows up there.
If you can't "rent" or borrow the tools, it seems pricey to buy them but in the long run it's way cheaper to replace the faulty part than guess and throw expensive parts at it that don't fix the problem.
And if you buy the diagnosis equipment, you still have it after in case anything else comes up down the road.

Cascade Special

Thanks for the responses. I really need some schooling on the fuel system/fuel injection on this thing. Most mechanical stuff I can handle but fuel systems have always been my downfall going back to aspirated carburetor days.

I really should invest in a code reader. Had a problem about a year ago with the transmission not shifting at normal speeds. Took it into the transmission shop with my hand firmly clasping my wallet. Twenty minutes later the mechanic called me and told me to come pick it up. All it was was a bad throttle position sensor. Picked up a new sensor on the way home and changed it out that evening. Thank goodness I know an honest transmission shop.

fltdriver

Until you get a reader the auto parts stores will usually give free readings (depending on state).

Cascade Special

Hopefully this isn't too late a response to avoid being one of those guys that asks for help and then never gives any feedback.

After giving it a full (admittedly long overdue) tune-up and doing all the fuel system checks I could, it ran smooth *** a baby's butt - but still had the same starting symptoms. So I finally bit the bullet and took it down to a local shop for a professional diagnostic. Turned out it was a bad coolant temperature sensor. The sensor read -40C with the engine warm so on warm starts it was flooding itself. Something I never would have thought of. Figures, three weeks of futzing around with fuel and ignition system for a 10 minute sensor replacement.

sdmartin65

With so many open ended threads it's nice to have a member that reports back on what the resolution was. The $20 coolant temp sensor can cause so much grief, it's the reason for more cracked radiators and blown head gaskets on vehicles with electric fans. The ECT won't normally throw a code unless it completely dies or starts reading high and that is rare.

Look into an ELM327 code reader, it's about $25 and is used in conjunction with your smart phone.

marktim

Is there a use by date (just a term ) on the temp sensor units mines the original by the looks of it and would be 25 years old now.
The old girls running well and I've changed everything that was needed to get it to run as good as I can .

fltdriver

The way I look at it: As long as you get a quality sensor the money will be well spent whether it's defective now or not, especially with something that can cause as many issues as the ECT sensor.