i have a anoying problem whith my f150 1997 4.2 4x2 the first start is very smouth then when the truck has been running for some time and the engine is hot and you cut it off for 10 minutes and try to start it, the engine shakes violently at first (very rough idle) then if you just touch the gas pedal and give it some gas it settles down. no codes i changed the plugs and wires last year now i changed the maf air flow put a new won i changed the gaz pump and filter and it those the same thing do any body can help me thank you

 

Try cleaning the Intake Air Controller (IAC) and the throttle body plate with spray can cleaner.
Remove the IAC to be sure the internal pintel is free to move and gets all the gum out.
Hold the throttle open by hand and spray all around the inside and on the plate.
Good luck..

 

thank you am goiing to do this today give you the news after if its better

 

I would guess this is a fuel pump issue. When it gets hot it can start shorting out and then smooth out later. Same thing happened to my 99 f-150. Had to replace the pump and it is fixed. If you suspect it is the pump, then I would pay ford to diagnose it first to make absolutely sure as the pump will run you about 400 dollars o.e.m. and you dont want to spend that money unless you are sure. But it sure sounds like the fuel pump to me. Hope Im wrong.

 

I changed the fuel pump one week ago and thats why a put this post my problem is still there when i changed the fuel pump there was a broken canister hose i fix it at the same time but the same thing going on when i start my truc hot after 10 min That the truc is sitting it start but shacks untill a press the gaz pedale if i put it in drive it get idle good yesterday i tied to clean hot the iac it was i little dirty by black gum oil any way i clean this and trottle with trottle cleaner and i dont see any difereence

 

I have never had any luck cleaning the Idle Air Control. It may work for a week or so. Then back to stalling. I invested in a fuel pressure gage to check pressure. You can check function of the regulator too.

 

I didnt see where you said you could give it gas and it then comes out of the bad idle. Sorry bout that. This sounds like it is a idle air control problem. Dont care that you cleaned it or not may not make much difference if it is heating up and then going bad. But it sounds like this is a idle air control problem. Again this is not a cheap part. I wouldnt just guess at this and spend money you dont need to. Take it in and let Ford do the diagnostic for 70 bucks and you will know for sure. I think the idle air control is about 140 bucks or so.

 

Thanks can i try anorher iac from another truc like mine could switch with my frend if this fix my problem go buy won after is this a good ideal thanks

 

No problem. Let us know if that does the trick.

But if for some reason it does not then please go and spend the money to diagnose this from FORD only. They can tell you what for sure it is then you can do what you want. It costs about 70 dollars. YOu would not have wasted the time and probably money on the fuel pump if you would have done this from the start. I think from what you are saying that this is a idle control issue since you can give it gas and it comes out of it, but after you try this if this doesnt do it then I wouldnt waste anymore time or money guessing on this... for what its worth. You have already spent too much time and probably your money trying by putting in a fuel pump you didnt need. Let us know.

 

No luck i did so it runs smooth in my frends truck but in my the it those not change noting i dont think its that the iac looks fine in bot truck i whent to ford dealer and got a date for the 24 april its a long time and the problem is still there its really when the truc is hot and i put the truc motor off when hot and start it 10 min after and it start good but secodes afters it start shaking alot if i press the gaz it calmes it selve after 3 4 shot on pedale when i put in drive and press the gaz it like it missing air but it goes very good after when i stop and go at stop or red light it those not miss at all if i thurn it off and back on it good and smooth if its 1 h after its good and in the morning to its really 10 15 min after shoting off its rough idle thanks for the help need more thanks

 

can this bee related to wen i chaged the camshaft synchronizer 1 year ago the sensor was broken and when a put the new won on i did it by eye is the 54 degres very important and cant this cause my problem thanks

 

Yes is can cause an issue if the unit is not set in and adjusted to spec.
It's controlling fuel injection timing.
Look in a copy of the Haynes manuel page 6-12.