Ok guys attached is the freeze frame data for codes P0171 and P0174. So far the vehicle has had plugs, all intake gaskets, IMTs, PCV and valve cover vacuum lines replaced, fuel filter, air filter changed, MAF cleaned. COILS have NOT been replaced yet.

I am 99% sure there is no longer a vacuum leak that would be substantial to throw the car into RP. Joel clears the codes, starts car and is immediately thrown into RP. After looking at the following data, does anyone see anything?

 

3 & 4 appear effectively not FF data

1 & 2 look the same

The MAF looks low, about 4.7 g/sec, I was expecting more like 7. But also running with lots of extra fuel so you pretty much must have air leak(s). That or I suppose you just about could have a faulty MAF. I'd go for the leak.

 

Thanks John, Joel has more FF coming. He is in class until late afternoon here. I believe he has FF while cruising around 45 MPH as well.

I replaced all but 2 vacuum lines, I did however did the tried and true test for leaks, lots of carb cleaner, not 1 hesitation afterward.

 

Look at the fuel trims at (say) 2500rpm (parked will do). If they head near zero you know you have an air leak - whether you found it or not!

You need an OBD tool that can do live data (data read and recorded and/or displayed in real time). Yeah, even an elm327

 

Using ElmScan 5, see link

http://www.amazon.com/ElmScan-Compac...=pd_sbs_auto_1

 

So look as I said

 

I agree the fuel trims are a bit high.

He mailed his elm327 to the owner of the car (I believe they are 3 or so hours apart) so the owner could scan the car and report back. We'll request that as well.

More to come.

Take care,

George

 

OK.
There's quite a bit of info about hunting lean codes on the net, such as Ford TSB 04-17-4

 

Did I miss the pm about getting to check out the elm? I'll pm my number to you Rick to see if I can meet up and check the elm out if he isnt too far from me.

 

Guys,

Rick I should have bought the scan tool I told you to get. My ebay elm327 wont connect to the software you sent me, so I had to use Scanmaster ELM instead.

I agree his fuel trims are WAY out of line.

Just for reference here's two baseline scans of my healthy 2003 3.0

Both done in park:

At idle:



At 2500 rpm:



Lets get Joel to do the same scans and compare.

Take care,

George

 

I emailed Rick more information from a data scan I did tonight. I need to know what's left to do and what information I need. That would be great, so that I could do this all 1 more time and be over with all the data scans. Rick knows what I've done so far

 

Can I assume that you replaced the lower breather elbow hose?
http://www.gusglikas.com/AutoRepair2...VacuumLeak.htm
http://www.gusglikas.com/images/Auto...otos/P0171.pdf

 

03+ 3.0's don't have one Gus...

Take care,

Goerge

 

Comparison OBD readings - great!

So, the MAFs are quite similar. Good. Unlikely to be the MAF.

But the trims are much richer AND the idle RPM is higher. An air leak would do that.
Remember it's a feedback system (when running CL closed loop), so this is how it will go:
Imagine the PCM would like to run at about 780rpm at idle. MAF says how much air is entering. Fuel added to match. O2 sensors say there's still lots of O2. PCM adds extra fuel until O2s show air/fuel is as it should be. Great, but with more air+fuel it's like having throttle slightly pressed and RPM is bigger than the 780 desired.

If the extra fuel trim needed is past a threshold (about 20%, commonly), codes are thrown to show that something's wrong.

When fixed, you can speed up the relearn of trims if you clear the KAM (disconnect battery if no OBD tool with that feature).

 

So I was told from George first to do the data scan, I was told to save information at 1000 RPM, 2000 RPM, 3000 RPM, and 4000 RPM. I can't get it to 4000 RPM and if I do, the OBDwiz program can't gather the information quick enough. Then I was told to take 2 more at 600 RPM and 2500 RPM. What is the main data I need to save other than Freeze Frame?

 

For some reason (I am a dumbbutt) I cannot post Joels comparison graphs, but reviewing the first FF in post #1 above, Joels MAP is reading 6.09 at 828 RPM, whereas Georges is at 9.87 at 789 RPM. I am wondering if the 39 RPMs make that much of a difference in readings.

 

I did not know that. Thanks!

 

Rick or Joel - email me a copy (you may already have).

Joel what we need is the following in park. First an idle scan. Car running in park, feet off the pedals.

Second, car in park, accelerator held to 2500 rpm.

We can't DIRECTLY compare the scans until we have the same conditions, it appears Joels Posted Freeze Frame data is with the car in motion at 8mph or so.

Take care,

George

 

drum roll..................

The solution is dot-dod-da-da!!!!!!

MAF Sensor!!!! (Autozone $86.00)

Joel replaced the MAF minutes ago and ALL is back to normal!!! No codes or RP.


Thanks to all who contributed!!!! One less vehicle going to the dealer.

AND a special thanks to srjag.....

 

Glad to hear it. What's left to do on this car at your house? I assume Joel will be making one more trip down there....