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Ironmike
Ironmike, Ford Technician
Category: Ford
Satisfied Customers: 3382
Experience:  30 years ASE Master tech L1 . Ford master
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Fuel Pressure JA: Sometimes things that you think will be

Customer Question

Fuel Pressure
JA: Sometimes things that you think will be really complicated end up being easy to fix with a Ford. The Ford Mechanic I'm going to connect you with knows all the tricks and shortcuts. Tell me a bit more about what's going on so he can help you best.
Customer: when drive it seem the truck does not have the pickup
JA: Are you hoping to fix this yourself?
Customer: yes
JA: Great! What have you tried so far?
Customer: I just check the fuel pressure
JA: Is there anything else important you think the Ford Mechanic should know about your Ford?
Customer: I have a code P420 I just replace the cat year ago now it back again
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the Ford Mechanic about your situation and then connect you two.
Submitted: 9 months ago.
Category: Ford
Expert:  Ironmike replied 9 months ago.
greetings, what is the year and model and engine of the ford truck? how many miles? what brand cat did you use?
Customer: replied 9 months ago.
2007 ford expedition 125000 ford cat
Customer: replied 9 months ago.
The old cat fail apart inside
Customer: replied 9 months ago.
You look inside cat in the front it looks perfect but when I took the o2 sensor out that when I found small pieces
Expert:  Ironmike replied 9 months ago.
yep, somewhat common. they have 8/80 federal emissions warranty on catalytic converters
Expert:  Ironmike replied 9 months ago.
there are 2 catalytic converters. you could need the other one replaced now.
Expert:  Ironmike replied 9 months ago.
did you ever replace the spark plugs? any other codes or just the po420
Customer: replied 9 months ago.
I change the plugs about 2 month ago 2 plugs where loses on bank 2
Customer: replied 9 months ago.
Just code p420
Expert:  Ironmike replied 9 months ago.
if you have misfires it can take out a cat. coils and plugs go on these.
Customer: replied 9 months ago.
No miss fire
Expert:  Ironmike replied 9 months ago.
did ford do the cat. I have seen aftermarket cats not California emissions last a short time
Customer: replied 9 months ago.
The SUV just does not have the pickup do you the fuel pressure is a problem
Expert:  Ironmike replied 9 months ago.
p0420 is low cat efficiency on bank 1(passenger side)
Expert:  Ironmike replied 9 months ago.
could be. worth at least checking it. P0420 is not a problem unless the cat is clogging.
Customer: replied 9 months ago.
Yes bank one is the cat i change and when I did the plugs there were 2 loses plugs because the where leak exhausted
Customer: replied 9 months ago.
The fuel stay at 70 psi and does not change
Expert:  Ironmike replied 9 months ago.
that is good for fuel pressure. You could clean the MAF sensor. parts stores sell spray cleaner for this. If they get contaminated it will cause performance issue. will not read how much air is coming into the engine properly
Expert:  Ironmike replied 9 months ago.
where did you get the cat?
Customer: replied 9 months ago.
Cat came from a ford dealer it was $2,000.00 had all the connection
Customer: replied 9 months ago.
I will check the MAF I have cleaner for that
Customer: replied 9 months ago.
One thing I noticed is the exhaust pipe by the tire it alway white not black like most car it been like this all the time I own it about year
Customer: replied 9 months ago.
Some people said the fuel should not be over 45 psi is this correct.
Expert:  Ironmike replied 9 months ago.
did you replace the cat monitor(02 sensor in the cat). I have seen when the cat fails and the element breaks apart it damage the sensor
Customer: replied 9 months ago.
I did not change the o2 sensor
Expert:  Ironmike replied 9 months ago.
it might have gotten damaged. if you have a scanner we could see if it is working. vehicles like this really need live data to diagnose performance issues. I have an APP on my phone(torque pro 4.99$) from google play and it works with a OBD2 blue tooth adapter(under 30$ off e-bay)
Expert:  Ironmike replied 9 months ago.
it works great with my Samsung phone, pulls codes, clear codes and shows live data
Expert:  Ironmike replied 9 months ago.
great too for DIY guys on the newer vehicles
Customer: replied 9 months ago.
I did live data it moving up and down my fuel trim on bank was reading 99.2%
Customer: replied 9 months ago.
The data read short term fuel trim bank 2 sensor 2 99.2%
Customer: replied 9 months ago.
O2b1s1 sensor reading between .095 -760
Customer: replied 9 months ago.
O2b1s2 reading between .095-.775
Customer: replied 9 months ago.
O2b1s1 reading between .065-.780v
Customer: replied 9 months ago.
O2b1s2 reading between .170-.800v
Customer: replied 9 months ago.
Any reading would you like me tell you?
Expert:  Ironmike replied 9 months ago.
bank 1 and bank2 sensor 2 should not change that much. sensor 1 sensor should change .1-.8
Expert:  Ironmike replied 9 months ago.
when cats work the cat monitors should read .4 or .5 some what steady
Customer: replied 9 months ago.
Both cat temp is 863
Expert:  Ironmike replied 9 months ago.
not temp, voltage they read
Expert:  Ironmike replied 9 months ago.
if the rear or back 02 sensors move the same as the front it usually indicates a bad cat.
Customer: replied 9 months ago.
I know it funny they both moving about the same s2 they should stay close to 0 volts
Customer: replied 9 months ago.
But bank senor doing the same thing and not get a code for that bank
Expert:  Ironmike replied 9 months ago.
you can try swapping sensors and see if the code switches
Customer: replied 9 months ago.
I will try that first
Expert:  Ironmike replied 9 months ago.
ok, let me know what you find, if the code changes
Customer: replied 8 months ago.
I move o2 sensor to bank 2 and clear code drove it for 15 mins so far no code now bank 2 sensor is read between .415v to .8v and if you press the gas pedal to the floor it does not have any power like no fuel or something when the rpm go up if start to pickup power.
Customer: replied 8 months ago.
Do think a cat could be clogged?
Expert:  Ironmike replied 8 months ago.
since you did one before you can drop the exhaust off the exhaust manifolds and then see if there is more power. That is how we test or we remove an 02 sensor and install a pressure gauge.
Customer: replied 8 months ago.
What about a throttle position sensor?
Expert:  Ironmike replied 8 months ago.
could be but I have never seen a vehicle with electronic throttle control have problems like this and not set codes. This truck does not use a throttle cable, controlled by the PCM. The MAF sensor could cause performance issues and not set a code. I would check the air filter, and clean the MAF sensor. parts places do sell spray cleaner for the MAF.
Customer: replied 8 months ago.
I did clean the MAF and check the signal voltage what I read about it says at 2500 rpm it should be 1.8 v and I see 1.6v and I will do the pressure test. What pressure should I see for normal?
Expert:  Ironmike replied 8 months ago.
you have an exhaust pressure gauge?
Expert:  Ironmike replied 8 months ago.
can you look at camshaft timing? I have seen phaser issues and even the timing chain jump on the 5.4L 3 valve issues. with an advanced scanner like the FORD IDS the tech could look at camshaft advance. if the valve timing is off or does not advance enough it could cause lack of power
Expert:  Ironmike replied 8 months ago.
I have verified a few with phaser issues by looking at the valve timing on live data.
Customer: replied 8 months ago.
Yes I can look timing what range should it be in?
Expert:  Ironmike replied 8 months ago.
IDS show desired and actual. they should both within 2-3%. They should both advance with increase of RPM. With live data you will see it when you compare bank one(passenger side) to bank 2(driver side)
Customer: replied 8 months ago.
Do you know what the MAF should read in grams per second at idea and 2500rpm?
Expert:  Ironmike replied 8 months ago.
let me check
Expert:  Ironmike replied 8 months ago.
still looking, site issues. From what I remember 6-8 at idle and 30-40 2500rpm
Expert:  Ironmike replied 8 months ago.
engine load and altitude do affect the readings
Customer: replied 8 months ago.
This is the reading I have g/s idle 7 to 8 and at 2500 rpm it was around g/s 26 plus LTFT1 is at 2.5 and LTFT2 stay at 0.8 how does this look?
Expert:  Ironmike replied 8 months ago.
what is the short term trim on each bank
Customer: replied 8 months ago.
STFT1 -0.8 to +7.0 and STFT1 -0.8 to +2.3 at idle.
Customer: replied 8 months ago.
What is this short term fuel trim bank 2 sensor 2? 99.2
Customer: replied 8 months ago.
Do you think MAF is reading low?
Expert:  Ironmike replied 8 months ago.
99.2 is for what ?
Expert:  Ironmike replied 8 months ago.
I don't think the MAF is bad
Customer: replied 8 months ago.
I'm going change the cat again they will not warranty it because it failed apart in the middle again the think I have a vibration in the pipe that is cause the cat to break apart. The truck runs great in open loop and when it warm up and go to close loop when it has power issue.
Expert:  Ironmike replied 8 months ago.
what was the short trim for bank 2?
Customer: replied 8 months ago.
Bank 2 fuel trim idle is around 5.0 to -5.0 drive on the highway it could does high as,+15 and if I give a lot of gas it will go to 0 or something I have send +99.5 to -100
Expert:  Ironmike replied 8 months ago.
normal fuel trims(short) should be from -5 to +5 changing . long fuel trims should a close to 0. if the fuel trims are high or in the + in means fuel is being added. if - it means fuel is being taken away. When ever repairs are made KAM(key alive memory) needs to be reset. either with a scan tool or battery disconnect. If the 02 sensors are working properly it show us what is going on. Higher RPM reading will change fuel trims. Lets reset Kam and then see what they are as the truck runs at idle. We might have a bad vacuum leak. Long term also tells us what the PCM has learned and adapted too.