PDA

View Full Version : GU patrol losing power



Karalyn
23rd September 2021, 04:55 PM
I have a 2001 Nissan patrol 3.0 turbo diesel. The issue I'm having is when I'm driving along it will drop power and I have to let my foot off the acceleration and put it back on and it seems to come right for about 200-500 yards and do it again. It's more on hills too. I've changed the throttle body, put another boost control regulator and cleaned out the intercooler. Not sure what is going on with it does anyone have any tips? Thanks

nipagu7
25th September 2021, 09:39 AM
sounds like you are hitting limp mode . do you have a boost gauge . if your boost is going over 15psi you can hit limp mode , if this is the case try reducing the boost . if you want to run higher boost the only way to get rid of limp mode is a remap .

growler2058
25th September 2021, 05:16 PM
G’day Karalyn welcome aboard
Auto or manual? What boost are ya getting?

phdv61
27th September 2021, 02:26 AM
On a 2001 Di, boost level has nothing to do with limp.
Limp only occurs when the MAF voltage
- exceeds 3.55V below 2000RPM
- exceeds 3.88V below 2500RPM
- exceeds 3.98V below 3000RPM
- exceeds 4.18V below 3500RPM
for more than 4s.

The ECM does not care about the boost level as such.
There is no need to have a huge boost to get limp. in fact down low, it is even counter-productive as all you do is create back-pressure and you just loose energy fighting against it.

> A remap will suppress the limp modes.

> Screwing down a bit the stop screw too.
> Adding a schottky diode or two in serie with the MAF signal will also decrease the MAF voltage a bit and will suppress limp.
However, reducing the MAF voltage will also decrease the quantity of fuel requested by your ECM to your IP.

After testing all systems available I ended up designing and developping my own electronic VNT controller driving the Nissan Solenoid to optimize the quantity of air swallowed by my cylinders at all Revs under load, and suppress limp too.
Search for "MAGIC BOX VNT" on the net if you wish to learn more about it.

Big Girl
5th February 2022, 02:55 PM
Karalyn, did you find your problem?

Regards, Louise