The sensor on the intake is a MAP sensor as well (technically TMAP as they measure both pressure and temperature). I've removed the sensors from both the intercooler and the intake and they are the same. I haven't removed the third sensor on the intake manifold but it is my understanding that all three are identical.

 

Thanks for confirming the typo in the manual!

It makes a lot of sense that the sensor on the air box would also measure temperature so that the ECU can see directly how much hotter over ambient the charge air about to be injected into the engine is.

When you say "identical" do you mean identical in appearance, or identical part number stampings in addition to identical in appearance?

All the best,
Mark

 

Lm stone 510 -

Its a bit more complicated. Generally speaking, tmap is a lower cost way of determining maf. Tmap senors are less expensive than maf senors. By measuringmtemp and pressure, and determining displacemnt or "pumping capicity of engine" ( fixed variable)' and rpm, it is pretty easy to determine mass air flow. The problem is the approach is a little indirect. I would guess that maf equipped cars are easier to hot rod by chipping or adding flow improveemnts ( free flow exhaust). Not sure about t map, because it depends on a look up table to figure out maf which is in theroy is based on the baseli e engine pumping capacity.....not compensated by improvements.

Hopefully this is not total confusion.....

My opinion ....maf is probablt best....but i am not sure we have one.

(Focus st is still a great car....either way .)

 

I ran a MAF on my 05 turboed focus. We were looking at relocating it from behind the filter to close to the throttle body for better tuning. With a map I would belive you get better data since it is in three locations. Much easier to see what the air is doing. Also this allows those who want to run a bov to do so with out running super rich everytime there car releases pressure.

Sent from my Galaxy S3.

 

Looking at the diagram in post #1, it seems that the three sensors are all designated differently:

• The sensor on the intake (8) is labelled MAF.
• The sensor on the intercooler (5) is labelled MAP.
• The sensor on the intake manifold (3) is labelled MAPT.

I thought they were all identical, but I could be mistaken. Alternately, the different names might be to make it easy for people to know exactly what sensor is being referred to. I'll have to let someone more knowledgeable chime in, since bad information is worse than no information at all.

 

No maf on this vehicle. That drawing from the Ford manual was deemed a typo a year ago by me

Speed density vehicle.

 

Same we we don't have multi disc clutch

 

Just to set the record straight.

Fuel injection depends on actual mass air flow. Most direct way to measure is by a maf sensor. Tmap determines maf indirectly by calculating what it shoul be based on temp, pressure, ( thermodynamically, pv=mrt), and rpm. Tmap can be made to work very well.....but it cannot ever be as versatle as a maf sensor which is generly the most acurate measure of maf.

All the best

Giff

(The company i work for manufactues automotive sensors)

 

Does the ECU literally use the ideal gas law for air? (Perhaps only a Ford engineer would know that...)

Doesn't that relationship go in the crapper at high pressure (turbo), high heat (turbo) and multiple species (humid air)?

 

This is all good info, thanks! I like facts...

This is my first car with MAPT sensors; previously only had MAF sensors. The problem I experienced had to do with the hot wire giving false readings due to either/both of voltage fluctuations and or gunk on the hot wire.

I asked because long term I'm considering an FMIC change and am concerned that the increase in FMIC volume will screw with the mapping.

Thanks,
Mark

 

Yes, reality is always a bit more complicated....my point is with temp, pressure, and engine speed mass airflow can be determined.....most likely a look up table vs a calculation. This to me is not as good as actually measuring maf. I would guess that our system is less adaptive to breathing improvements vs maf. The general trend is towards tmap vs maf.....

Best regards
Giff

 

Thanks Giff,

If all three sensors are indeed tmap, I confess I like the redundancy of the two sensors located in the cold side of the intercooler and on the intake manifold.

I'm still concerned that a significant percentage increase in the volume caused by upgrading the FMIC needs to be accounted for in the mapping. I know in most custom tunes there is a parameter for FMIC volume, presumably to compensate for the increased turbo lag a larger FMIC volume would otherwise create.

But, to my knowledge the major tune providers do not alter their maps based on FMIC volume; you get the same map whether you've put in the monster cp-e/Steeda FMIC or not. So perhaps the 3-sensor mapt system compensates on its own... Perhaps I'm overthinking all of this?

Thanks again,
Mark

 

Mark-
You are not over thinking it. I am sure there is some type of increase inperformance without a re-map. But, i think the big gains you could see with breathing increases will not be seen with mapt without a remap. My 95 taurus sho could see as much as a 50 percent increase with flow improvements. That said our little 4 cylinder puts out 20 percent more than my stock sho. Basicaly i am satisfied so far....but the big increase from flow improvement might not be had as easily as in the maf days.

Btw, where in maine? Used to live in alfred back in the 80's....still have friends in the pine tree state.

Best regards
Giff