Limp Mode question

by **rlees85** » Sun Jul 29, 2012 3:15 pm

I was just wondering, on a turbo-diesel, does limp mode cut JUST the fuel, or does it also try to cut boost also (I assume by opening the wastegate fully) ? ?

Just curious...

by **ecuedit** » Sun Jul 29, 2012 5:27 pm

There is limp mode map, fuel cut. Thats all. ;) EDC15...

by **hinkxx** » Sun Jul 29, 2012 6:26 pm

ecuedit wrote:There is limp mode map, fuel cut. Thats all. ;) EDC15...

While limping a few times on the freeway :? , IIRC I could not get past 3000 RPMs or 100 km/h.

How would this look like in a map? Shorter RPM axis?.. or a limit is imposed on map values..?

by **ecuedit** » Sun Jul 29, 2012 6:38 pm

Map 12x1, RPM vs. IQ 0-5000RPM, factor 0,01, you can check in this file:
peugeot-406-2-2hdi-2002-4hx-edc15c2-original-t9

ADDRESS: 689E2

But tuning the limp... :|

by **OdinEidolon** » Sun Jul 29, 2012 11:26 pm

ecuedit wrote:But tuning the limp... :|

:D

by **hinkxx** » Sat Aug 04, 2012 1:10 pm

OdinEidolon wrote:
ecuedit wrote:But tuning the limp... :|

:D

I knew it was a question of time before I stumble on somebody or some software that would exactly this :), and I quote a guy here http://www.vwt4forum.co.uk/showpost.php ... stcount=42:

Please could I advice anyone thinking of having a DPF Delete done on there VAG vehicles to fully check who is doing it as there are many in the UK offering this server now due to a "Patch Software" called "ECUSafe" http://www.ecusafe.com

All these tuning companies do is run the original file they download from you engine control unit through this ECUSafe patch software and the software generically patches the original software.

What it does is kills around 50% of ALL DTC's (YES AND I MEAN MANY OTHER DTCS NOT RELATED TO DPF AS WELL) then it just sets the DPF Matrix to "0" and finally Tunes a "LIMP MODE MAP"

So the ECU itself still is running the DPF system, but not engine management lights will come on due to them being totally deleted and also when the ecu does put it into limp mode it will run as normal as the limp mode map was tuned.

There is only 1 correct way to do a dpf delete and this is to totally turn the "DPF Function" off within the software and this silly patch software "ECUSafe" cannot do that as the "DPF Function" is different on all ecus.

Another software they also use is one called "Swiftec" works that same if not worse that "ECUSafe"

Honestly the only correct way to do this is with using a hex editor and also knowledge of the complete DPF Matrix System

:lol:

I agree with the poster, and the sad thing is that UK is probably not the only country to worry about these cheap tuners :?

by **RPM freak** » Sat Aug 04, 2012 3:06 pm

The poster (a tuning company from UK) is only 50% correct.

They must criticize other people work so they can boost sale on there own remaps. They forget to mention that in some files ECUsafe works flawlessly (no DTCs are erased, no limp mode changed). For Swiftec (a tuning company from Portugal) a can not comment because a have never used there software.

On the end i must say that no mater what software is used to do DPF/FAP off files, the user must exactly know what is he doing and how the DPF/FAP system works in the car that is being worked on.

by **Alex.T** » Tue Aug 14, 2012 1:55 pm

How do you know when you are in LIMP mode?
(besides not being able to get over 3000rpm and 100kph)
From edc15c2 manual I read that ECU manages downgraded modes when some crucial sensor fails.
So I guess you go into limp fo example when your rail pressure sensor fries.
Is that right?

by **ecuedit** » Tue Aug 14, 2012 2:41 pm

You know it when your fuel is cut dramatically.
It happens on some critical errors.

There is a lot of reasons how do you get to the limp mode. Basic thing is the fuel cut when this happens.

by **Relic** » Tue Aug 14, 2012 2:47 pm

In my edc16 honda O actually have two 25x1 tables.
One is NM and one is IQ.
They basically kill the engine at 2000rpm+ or similar and cut power about 50%.

The dpf issue does not surprise me.
Many civics lose cruise control when applying this patch for dpf delete.
WTF!
Says everything really about correct tables and map areas being updated.

Theres one doing egr delete...
...except any logging software shows the egr as fully active and the egr error operational.
They say its simulating...I say...you aint doing it right if you need a simulator :lol:
Theres a 25x1 temp table that kills EGR at 0c or below :roll: