---===The Official MAFT-Pro Thread===---

[f100skipper]

Hello to you guys from another UKer.

I currently have a MAFT Pro running speed density on a 1993 GTO TT. The car has 13T turbos,550 injectors,Walbro fuel pump with hotwire.

I initially had the car running with a bin file kindly donated on our UK GTO owners forum. Tha car ran reasonably well for a few test runs, then next time I came to start it, nothing!

The car cranks over ok and stinks of fuel but will not fire up.I suspect it could be the MAP sensor. I have checked for voltage at the sensor and all seems ok. When I checked the sensor status in the MAFT Pro MP was giving a reading of 280 KPA with the ignition on and no change when cranking the engine over. I'm sure I have read that the reading shoud be around 100 KPA.

I would very appreciate any input.

Regards

Mark

[TurboBob]

You are absolutely correct. That MAP reading is way too high and will prevent the engine from running.

It sounds like the ground connection to the MAP sensor is bad. But you should chase all the MAP connections and the grounds for the Pro.

Bob

[f100skipper]

Thanks Bob

Will check it out tomorrow morning!

Mark

[f100skipper]

Just ran outside and had a check

These are the readings I took from the back of the 6 pin plug with ignition on.

MAP sensor Pwr = 4.96v
Map sensor signal = 4.30v

MP still reads 280 ?????????

Regards
Mark

[TurboBob]

measure the ground at the MAP sensor.

[f100skipper]

Thanks !
Will check it out.

Mark

[msassoon]

I tried out 4.85, but to be honest, this is not helping me. The pt tracking delay means the car is still cold when the pt cuts in. I still think the ability to extend the afterstart time would be more useful. Just my thoughts.

Also, it seems I have a problem with WOT, and not sure if the Pro can help. At 4000 rpm and WOT, the AFR starts to drop off the scale, but AFR Tracking is trying to adjust to get to 11.5. It adds 25% and gives up as it has reached the limit. Does the user tune get added to the AFR Tracking? So can I add more fuel in the Low/Mid user tune or Mainscale to help? Or should I be looking at fuel pressure and injector sizes?

[TurboBob]

We should talk more on the afterstart stuff, I'm sure we can figure out a way to improve your issue.

On the AFR, when you say "dropping" do you mean going lean?

You absolutely need to be sure your fuel pressure is up to snuff. Fuel delivery (pumps, wiring, etc) is one of the biggest issues with fuel injected cars. Watch the injector dutycycle on a logger and make sure you are not maxing out.

The AFR correction is on top of the other tune variables. The idea is to tune the main tuning pages to reduce the ammount of AFR correction required. I typically tune on the rich side and let the tracking pull some fuel out.

On the Pro, you need to be absolutely sure that the wiring and hose connections to the MAP sensor are perfect. All fuel delivery in Speed Density mode is based on the MAP signal.

Bob

[msassoon]

Yes, going lean. I have checked all the appropriate things, I just guess my exhaust and intake changes are causing more fuel to be required.

[TurboBob]

once you are sure your fuel pressure is ok, you can add some fuel in the high load page to fix it. If you want to dig deep into it, you could tweak the VE table in the Pro...... The end result is pretty much the same tho.