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Hard to start after engine is warm

I have a 1989 Ford f150 that is hard to crank after the engine is warm/hot. If the engine is cold it will ‘hit’ on the first attempt, but after being driven for a couple of miles it takes several attempts to crank it up. I have replaced the oxygen sensorand the control module (in the distributor) to no avail. I have been told that eventually it will get to the point to where it won’t crank at all. Can anyone help me out? I have taken my truck to two different Ford dealerships and they could not find the problem.

Hard To Crank Or Hard To Start-Up While Cranking Normally?

Are we talking about one problem or two? Does the starter crank the engine over the same whether this thing is going to fire up on the first try or the second or third try? Is the problem just in the spark/fuel/compression area? Is there any problem in the starting system?

The starter cranks the engine over the same no matter how many times I try. I have replaced the spark plugs, rotor button, distributor cap, both gas filters and air filter. I haven’t had a compression check as of yet.

How old are the spark plug wires? How many miles on them. They don’t last forever.

Is there a tendency to have the problem when the humidity is high or it has been raining or snowing?

The spark plug wires are new also and it doesn’t seem to matter what the weather is outside or what the season. I have had the truck on a dianostic machine at two different dealerships and a shade tree mechanic and no one as of yet can come up with a remedy.

Have you figured out yet whether or not it is fuel or spark? Pull a plug or get a tester & check for spark next time it won’t start. If you have spark, blow some starter fluid into the intake and see if that helps - if it does worry about fuel.

Are you smelling any gasoline when you’re trying to restart, and/or if you get it rolling does the exhaust smell of gas? Is this fuel injected or carbureted?

This is a fuel injected truck and I burn regular unleaded.

If no one has, have a look at the fuel pressure pressure regulator - pull the vac hose & see if you have fuel in there.

And add to the list for next time it won’t start - floor it like its flooded, and if this gets it rolling suspect either the fpr or leaky fuel injectors.

I had the fuel pressure regulator replaced a couple years ago all due to excessive fuel usage (I was getting about five miles per gallon). Someone told me that there is a sensor that tells the computer how much fuel to allow to the injectors that might be defective. Is there such a sensor and if so what is it called?

I have a 70 cutlass with a 350 rocket and this happens to me all the time when the car is warm, especially when its above 75 degrees or more outside. And yes I do smell gas, lots of it! I have a rebuilt engine with new distributor plugs wires etc. the thing is it has been doing this the whole time since its been rebuilt. I did put a new edelbrock 4 barrel carb and manifold in it when it was rebuilt. I never considered that it could be the compression, the car doesn’t have as much get-up as I expected when it was redone. can be sluggish at times when its warmed up and hot outside. Thanks for any advice!