Solved CODE P0171-P0174.

[Josergiraud]

Got this code for my '07 4.6. By reading previous posts it could be the intake gasket. I also have a strong fuel smell on he cabin, but no fuel leaks whatsoever. Do a faulty gasket will produce the fuel smell? I like to research before changing parts that are not the solution. Thanks in advance

 

[BrooklynBay]

Welcome to this forum! Spray intake cleaner on the side of the manifold then see if the idle changes for a few seconds.

 

[Josergiraud]

I'll let my mechanic know. I'm still replacing the intake gasket because the fuel smell.

 

[Josergiraud]

I replaced so far the intake manifold gasket, fuel pump, MAF sensor, gasoline filter, fuel pressure sensor and now the truck hesitate to start, it cranks for like 4 seconds before turn over. Don't know what else to do. Sometimes gives me the code P0174, P0171

 

[Rcflyer330]

I replaced so far the intake manifold gasket, fuel pump, MAF sensor, gasoline filter, fuel pressure sensor and now the truck hesitate to start, it cranks for like 4 seconds before turn over. Don't know what else to do. Sometimes gives me the code P0174, P0171

Is it a slow crank?
How about when was the last time plugs where changed?

 

[Josergiraud]

Is it a slow crank?
How about when was the last time plugs where changed?

I also replaced the battery, spark plugs and the rubber boots

 

[Josergiraud]

I also replaced the battery, spark plugs and the rubber boots

And both O2 sensors

 

[loooney2ns]

Has a mechanic looked it over? You're just throwing money at the problem. Get a good mechanic to look it over correctly and find out what's wrong with it before spending any more money.

 

[D Hook]

I also replaced the battery, spark plugs and the rubber boots

By rubber boots, do you mean the coils?

Did you use the motorcraft coils?

 

[Josergiraud]

By rubber boots, do you mean the coils?

Did you use the motorcraft coils?

Hi guys, this was the problem. For the delay at starting after 4-5 seconds cranking, was the fuel pressure sensor, it was bad and all the fuel wad leaving the system and of course, to start up again needed to build it up. I replaced about a year ago but I bough a cheap one in ebay. Lesson learned.
For the codes, the park plugs were messed up, my guess is it was a snow ball efect from the sensor. I also had a bad coil. The shop replaced the coil, the sensor, the plugs and the truck is running flawless.
I spent a lot of money chasing a rabbit when I should get a trap. As I mentioned, lesson learned.

 

[BrooklynBay]

Thanks for the update. Your thread is now marked as solved.