4.2 v8 sc

PCV. Slowly bringing this old girl back to life, currently dealing with lean codes bank 1 and 2. I’m pretty sure it’s a vacuum leak ltft gets better when i rev. Smoke tested today but couldn’t find a single leak. I took the PCV off and I can blow through it in both directions. Can someone please tell me if this is correct? Thoughts are the Pcv will give me a lean but won’t give me a leak test.

This is my last code to conquer so any help will be appreciated 😀
Please see the thread. I think you’ve read one comment and jumped to conclusions 😜. It’s all there

Which 1 did I read?

You have a “lean code” Which could be caused by your PCV yes, but you have a low fuel pressure reading which funny enough🤔
rail pressure at 1500 rpm is 45 psi which is well within specifications.


Oh 48.5 psi at idle is what I see in the manual I have. (2007 4.2sc)

If you can’t answer simple questions or understand the use of live data then fine.


So crack on pal:p.

J
 
Which 1 did I read?

You have a “lean code” Which could be caused by your PCV yes, but you have a low fuel pressure reading which funny enough🤔



Oh 48.5 psi at idle is what I see in the manual I have. (2007 4.2sc)

If you can’t answer simple questions or understand the use of live data then fine.


So crack on pal:p.

J
You are commenting to two people. Myself the OP and another guy…so absolutely no need to be an asshat but also, crack on pal 🤣
 
You are commenting to two people. Myself the OP and another guy…so absolutely no need to be an asshat but also, crack on pal 🤣
Well for that I will apologise.
I’ve had my computer on it hence knowing what the fuel trims are doing. It’s lean and gets better under load. MAF sensors or fuel starvation wouldn’t get better under load fuel trims would get worse. it would become leaner?. MAF is reading around 5/6gs on idle which is where I’m lean. Fuel pressures are around 35psi on idle give or take. Unless it’s nothing to do with the sensing wire and the MAF is just throwing random numbers in but data streaming shows a very even and predictable reading. So looking at the above that’s how I came to my inclination of it being a vacuum leak but I’m showing no leaks…the only thing I’ve done recently is run some cleaner through the petrol.

But I will refer you to my last post stating what fuel pressure should be at idle.

So I will leave you perhaps not jumping, as it was mentioned in post#7.

which was another reason to ask if you could see/record live data.


J
 
So at idle my 4.2 sc reads,
Maf 6.5-7g of air
40psi fuel pressure at idle after 20seconds
Long term Fuel trims Bank 1 3%
Bank 2 -0.78%

At 1500 rpm stationery
Maf 14g
Fuel pressure 50psi
Ltft bank 1 -2.1%
bank 2 -1.5%

I can only get my fuel pressure below 40psi on coasting throttle while its loosing speed
 
So at idle my 4.2 sc reads,
Maf 6.5-7g of air
40psi fuel pressure at idle after 20seconds
Long term Fuel trims Bank 1 3%
Bank 2 -0.78%

At 1500 rpm stationery
Maf 14g
Fuel pressure 50psi
Ltft bank 1 -2.1%
bank 2 -1.5%

I can only get my fuel pressure below 40psi on coasting throttle while its loosing speed

In true British fashion it’s fixed itself slightly and created something new 🤷🏻‍♂️ yesterday lifts were +18% on idle dropping to near 0

Idle ltft b1 0% b2 7%
MAF 5.26gs
44psi

1500
B1 +10% b2 +13%
MAF 10.4gs
47psi

2000
B1 +4.69 b2 +5.47
MAF 13.48gs
45psi
 
Well, I drove a whole day with no MIL light on…no idea what was wrong or why it was doing it 🤷🏻‍♂️ will await to see whether it re appears.
 
Just one in tank pump, bowl filter as part of the assembly
Service is due and since I’ve had issues with lean etc want to change to fuel filter. Cant seem to find anywhere that gives me any info on it or a price. What’s the crack with it is it? Do you know a part number?
 
Service is due and since I’ve had issues with lean etc want to change to fuel filter. Cant seem to find anywhere that gives me any info on it or a price. What’s the crack with it is it? Do you know a part number?
Iv not changed mine or even been under the back seats of mine 🤣
 
Sure the 4.2 doesn’t have a fuel filter. Iv tried and can’t find any part for it. I did read it’s just a fine mesh over the pump/ sender unit in the tank, a case of leave it then change of it fails.
 
Sure the 4.2 doesn’t have a fuel filter. Iv tried and can’t find any part for it. I did read it’s just a fine mesh over the pump/ sender unit in the tank, a case of leave it then change of it fails.
That’s good to know. I did have look at the assembly yesterday and saw the little cone shaped strainer. It wasn’t dirty but I gave it a clean off anyway since I was already in there
 

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