Can / Should the MAP sensor be adjusted in remap

Scullies

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I have my S3 remapped with a custome map. When I drive it hard it gets thrown into limp mode.
I have swapped the n75 for a new one, still get limp mode. I logged the charge pressure (actual value) and noted I get 2530 mbar when it get thrown into limp mode.

17963 - Charge Pressure: Maximum Limit Exceeded
P1555 - 35-10 - - - Intermittent

I read that the MAP sensor is rated at 2.5bar.

Can or should the ecu be adjusted in the remap to accomodate the extra boost.
Or should I get the boost adjusted?
 
That shouldn't happen if the mapping was done right... what was the requested boost when the actual hit 2530?

Yes the MAP sensor is 2.5bar but again not really relevant in this context...

What map is it?

<tuffty/>
 
Thanks Tuffy, I will take it back in the morning and get them to look at it.

We don't have REVO, APR, or GIAC here. The company that did my map does the mapping for the Dubai Autodrome race cars, Seat, Audi and VW Gti.
Dont actually know what map he has done.

This is what I logged.
Image2.jpg
 
Not the best log mate if I am honest... needs to be a full throttle run in third from 2k to redline then you can see the relative data more easily...

The boost deviation looks high but without a proper run I can't tell whats actually going on... if the run starts further up then ideally wanna see the data from the start to work out whats going on

<tuffty/>
 
Actual is passing specified although we dont know what requested is, by more than 300mbr hence the limp mode. This is the charge limit protection kicking in.

This only affects pressures below the 2550mb limit. Above this the map sensor can't measure boost do the difference could be 1000mb and it wouldn't trip.
 
I will go try another run this morning, 3rd gear pull from 2000rpm, but it normally hits limp mode and I cant get to redline.

Are there any specific blocks I should measure that you need to see, or are the ones above ok?

Cheers
 
Like I said above your making more boost than requested and throwing the error. I'd start by checking thè pipe from the n75 to the actuator to make sure it's connected or not split. Also check the n75 is connected the right way round . Also make sure you can manually move the actuator as it might be seized.
 
I will check the hose and manually check the actuator, when its cooled down

I dont get the limp mode on every run, I did a long run this morning, 3rd and 4th gears with no fault.
Then I did a few more little runs and tried another 3rd gear run, and got the limp mode.

Here is the log from the 3rd gear
Image1.jpg
 
I will check the hose and manually check the actuator, when its cooled down

I dont get the limp mode on every run, I did a long run this morning, 3rd and 4th gears with no fault.
Then I did a few more little runs and tried another 3rd gear run, and got the limp mode.

Here is the log from the 3rd gear
Image1.jpg
I'm taking it this log didn't give you limp?
 
I think I need a new MAF, I cleaned the sensor but still get low readings.


Yip, no limp on previous run in 3rd.

But into limp on run as below, started in 3rd all the way to redline, changed to 4th and into limp mode. As you can see I got over 2500mBar in 3rd and no limp mode and the log says I didnt reach 2500mBar in 4th but into limp mode. I was watching my boost gauge while in 4th and WOT ( good thing the roads out in the desert are long, straight and empty :scared2:) boost gauge says I was getting 1.6Bar of boost. So I'm guessing that should be over 2600mBar. Should I also clean the MAP sensor??

http://i1253.photobucket.com/albums/hh584/Scullies/limpstart.jpg?t=1336225290

limpstart.jpg
 
5440 rpm 5640rpm 4 th gear. Specified is 1930 and 1500 and the actual is 2420 and 2210 respectively. This is above 300mb limit. 1930-2420 = 490 . 1500-2210 = 710mb. There's your reason for limp. You can also see the n75 is down at 12% as it tries to gain control of the boost but by then it's too late. Has it done this since a remap?
 
Yes, it never went into limp before remap. Only happened after remap, would you say there is something wrong with the map.
I havent had a look at the pipe work for the n75 yet or the wastegate actuator. Will check those in the morning.

Out of interest what is the specified value? Where does this value come from?
 
Specified boost comes from the load maps. You request a load with throttle and rpm and then the ecu calculates how much boost is needed to create that load value. This is done via the turbo and controlled by the n75. However there is a slight delay from requested to actual and hence boost spikes can occur.

Eliminate hardware issues 1st and then you can then say its the map.
 
Ok, so after I have checked the vacume hoses and replaced the MAF and N75 valve, I was still getting overboost limp mode. Took it back and they said they have adjusted the map. So far no limp mode. I did some logging today, as I feel the boost tapers off pretty quickly after peaking around 1.5bar. Is this normal or does it look like I'm loosing too much boost.
Does this log look OK

logwithmapchanged.jpg picture by Scullies - Photobucket

logwithmapchanged.jpg
 
Looks like something else is intervening as load is dropping off... you are only ever on full load (191.7) for about 1000rpm... something else is pulling load there and the N75 is running flat out for no apparent reason...

Lots of really weird shizzle happening there...

<tuffty/>
 
:sadlike:
Would the temperature here in Dubai have a effect on the g/s figures. I know with customers boats, the inboard V8's lose a lot of power over the summer as the air temp gets pretty warm.
Is g/s value changed in the remap, or is this just a reading from the MAF.

Would the waste gate actuator need adjusting, it feels like the boost is escaping when I get past the 4500rpm area. Should the wastegate stay completely closed until there is a vacuum applied to the actuator?
 
:sadlike:
Would the temperature here in Dubai have a effect on the g/s figures. I know with customers boats, the inboard V8's lose a lot of power over the summer as the air temp gets pretty warm.
Is g/s value changed in the remap, or is this just a reading from the MAF.

Would the waste gate actuator need adjusting, it feels like the boost is escaping when I get past the 4500rpm area. Should the wastegate stay completely closed until there is a vacuum applied to the actuator?

Not to that extent... wastegate is not the issue here its still the map IMO... if done right you will see it on full load throughout the run... if the wastegate was closed and you are still only make that boost then your turbo is shot... thats not the problem here

If you think you have a leak then I suggest you check for that first... you can't trouble shoot this until the engine is in perfect condition... if you have a leak somewhere you will be chasing your tail and making pointless changes to the map that once fixed will throw the map out again...

<tuffty/>
 
Thanks for your input tuffy, I will whip out the boost leak tester and check for leaks, just to make sure. Then back to garage, thinking about asking for my money back and sending my ecu overseas to get mapped !!!
 
get yourself a galletto and files can be sent to you to flash yourself.... if you wanted to do that sort of thing
 
So....... boost leak revealed a nice big leak under the mani. Damn old rubber !!!!
Will need to take it for a drive on a cooler day, today was 44 !!

OOOOH, this galletto sounds fun. I would definately be interested in something like this.
But what stops someone from saving the remap off another car and loading onto their car?
 
So....... boost leak revealed a nice big leak under the mani. Damn old rubber !!!!
Will need to take it for a drive on a cooler day, today was 44 !!

OOOOH, this galletto sounds fun. I would definately be interested in something like this.
But what stops someone from saving the remap off another car and loading onto their car?

if not port read protected nothing..

needs to be identical ecu/software ideally, not just any car

why would you care if its your car/ecu tho?