Rough idle after hot start 2004

[xcvcpbf]

I now have the same issue as many. When car is hot, after sitting for over 10 minutes, it idles VERY rough for almost a minute before smoothing out. Here is what I have done : new NGK Coils, new NGK ruthenium spark plugs, new throttle position sensor, 4 new oxygen sensors, new air filter, thouroughly cleaned every nook and cranny of the Throttle Body (it wasn't even dirty) Cleaned the MAF Sensor (which had been recently replaced) New fuel filter, New Fuel Injectors, New Fuel Pressure Sensor, and Techron and HEET ISO in the gas tank - and it still happens.

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[Mrdan]

I now have the same issue as many. When car is hot, after sitting for over 10 minutes, it idles VERY rough for almost a minute before smoothing out. Here is what I have done : new NGK Coils, new NGK ruthenium spark plugs, new throttle position sensor, 4 new oxygen sensors, new air filter, thouroughly cleaned every nook and cranny of the Throttle Body (it wasn't even dirty) Cleaned the MAF Sensor (which had been recently replaced) New fuel filter, New Fuel Injectors, New Fuel Pressure Sensor, and Techron and HEET ISO in the gas tank - and it still happens.

You need to put a monitor on it and check the fuel trim cold and hot it should stay around 0 - 1 or 2 if it goes positive + 1 or above you have a vacuum leak, or you may have a injector leaking, these are a couple of things I’d check first, it doesn’t sound like a fuel pump issue

 

[Mrdan]

You need to put a monitor on it and check the fuel trim cold and hot it should stay around 0 - 1 or 2 if it goes positive + 1 or above you have a vacuum leak, or you may have a injector leaking, these are a couple of things I’d check first, it doesn’t sound like a fuel pump issue

Another thought is the timing chain tensioner witch is operated off the oil pump, ford over the years had many problems with this on a lot of there engines, I use Amsoil in mine and never had a issue from day one