Issues with a PO171 code? 5.4L

[BCam]

Before you remove the sensor to replace it or go to any great diagnostic links, unplug your sensor and clean the contacts on the plug and the sensor with spray electronic contact cleaner. This worked like a charm with my fuel rail pressure sensor on my E350 V10. WD-40 makes a contact cleaner.

[JWA]

Originally Posted by BCam

Before you remove the sensor to replace it or go to any great diagnostic links, unplug your sensor and clean the contacts on the plug and the sensor with spray electronic contact cleaner. This worked like a charm with my fuel rail pressure sensor on my E350 V10. WD-40 makes a contact cleaner.

That's a great idea BUT if you go that route please make sure you're using a dedicated electrical contact cleaner/lubrication product, one specifically for the automotive industry would be best.

Not sure this is helpful but most any vehicle electrical connector I'll lightly coat the terminals with dielectric grease. Since these tend to have a self-wiping action the actual contacts achieve great contact, the surrounding areas somewhat well sealed against moisture or humidity.

[lashidalgo]

I also have the p0171 in a 5.4!
I'm at 198***mi with the 5.4l on a 2002. I've had this code for the last 2 years. Over the 2y I've changed O2, maf, redo all vacuum and fuel hoses, EGR and selenoid, purge valve, coils, plugs, pcv, iac, fuel pump, throttle body gasket, tested cats. My trims are off the charts -30,+10 ... At this point, I'm suspecting an exhaust leak. The van has enough power to move around.
Sometimes when is cold I hear this humming sound, I traced it back to one of the cats, it might have a hole somewhere or maybe is up the line, you know a broken stud....

[deserteagle56]

Originally Posted by lashidalgo

Sometimes when is cold I hear this humming sound, I traced it back to one of the cats, it might have a hole somewhere or maybe is up the line, you know a broken stud....

When my rig (2007) is cold it sounds like it is falling apart, what with the racket coming from underneath. But it has 4 cats on it and all that noise comes from the heat shields attached to the cats. I confirmed this by climbing underneath it and just by pressing down on the heat shields I was able to abate the noise. One of the spot welds holding one of the heat shields broke and that one really caused a racket until I put a clamp on it.

[leemyrah]

I hope this message doesn't hijack the thread.

I have a 2001 E250 PleasureWay conversion with a 5.4 L. How do I tell if it is a 4R100 or a 4R75?

Thanks.

[JWA]

Originally Posted by leemyrah

I hope this message doesn't hijack the thread.

I have a 2001 E250 PleasureWay conversion with a 5.4 L. How do I tell if it is a 4R100 or a 4R75?

Thanks.

Its certainly out of place, would have been better posting this as its own thread or question. I've posted an ID image that will be helpful.

[Cyrull]

Here are the most common issues as it relates to your code.

[BroncoHauler]

Originally Posted by leemyrah

I hope this message doesn't hijack the thread.

I have a 2001 E250 PleasureWay conversion with a 5.4 L. How do I tell if it is a 4R100 or a 4R75?

Thanks.

Originally Posted by JWA

Its certainly out of place, would have been better posting this as its own thread or question. I've posted an ID image that will be helpful.

Yeah, it's not keeping with the thread issue, but more importantly for you at least, is that you're less likely to get a reply to your question.


Herb

[AdventureVanNW]

Thanks everyone, turned out to be the intake manifold gasket. Appreciate all the help.