Hey guys, did a search and couldn't find anything (which REALLY surprised me)... just wondering what you guys thought of doing a 5.0 MAF swap. the ones off the 5.0 cobras, with a string sensor. IMO, most efficient and apparently a very smart sensor.

 

my friend did this on his 3.0 taurus and it killed his cats... so i would not do it

 

Hmmm.

 

lol! For all I dissed Dave on this issue, if you put the calibration out too far, for too long, you can do damage. You have NO IDEA what the calibration of the 5.0 MAF is and just swapping it is not sensible without a lot more information.

 

And you won't know until it's too late.

 

my cats are gone so it doesnt matter

 

Cue the violins!

Actually, if you pay more attention to detail than I did, you can use a scanning tool that allows you to watch PID's to verify that your not at the extreme limits. Had I done that, Doc would not have gotten the CEL on the MAF mod on his truck.

So you CAN know before it's too late -- you just have to actually LOOK!

 

Who'd a thunk it

 

Each MAF sensor design has a unique transfer function that describes the mathematical relationship between the sensor voltage and the measured air flow. This is arrived at empirically and flashed into the PCM. Mixing MAFs and PCMs from different applications is asking for fueling errors and their consequences.

 

Absolutely. For some reason, when cut, the 3.0's don't move so extremely far off the curve, and the 4.0's do.

It's strange to me because the 3.0 sensor fills more of the cross section and I would expect the change to be more severe when cut. But in fact it's the other way around.

 

Anyone seen any info on this? It is a very convincing switch to me, but I can't even find any pics of the string MAF...

 

I've seen no info, and what we just told you should make it a less convincing switch. THINK ABOUT IT: that MAF is designed to scale the signal for the full range airflow of a 5.0L, high output engine. Do you really think it's range is going to be even CLOSE to the right range for a 4.0L Ranger SOHC?

What is it exactly that is convincing to you about it?

 

Which PID is that?

 

Excuse my ignorance but what is a MAF "string sensor"?? Are we talking about a common hot-wire sensor here or something else? If it is not a hot wire sensor, the chances of it even functioning with a calibration set up for a hot-wire sensor is just about nil.

 

I already posted that, Dave, in the other topic: LTFT and LTFT2

I take it you know what they represent and how they are derived?

 

Long term fuel trim will not tell you what the catalyst temperature is, that why I thought you must be talking about something else.

 

I never said it told catalyst temperature. I said it would tell me if the MAF was out of range and causing a lean or rich condition. You indicated that you needed those conditions to damage the CAT. Hence, if fuel trim is "under control", there would be no catalyst damage from a lean conditions. Q.E.D.

 

If fuel trim was under control you would not have had any CMDTC's.

 

Gosh, you don't read anything I actually type do you, Dave?

I SAID I didn't read the LTFT's above idle when I FIRST did the mod, and missed that it was at the limit. I said that was a MISTAKE and I should have done it. When Doc came back I DID read them, and discovered the reason for his CEL.

You don't let up in the face of facts, do you, lol! If you read my topic on it, you would have known you are running a rabbit trail on this one. I've already answered your questions and challenges, before you posted them. Are you just ANXIOUS to make a negative point, or are you interested in what actually happened?