2012 stx550 Limp mode

[calvin stewart]

I have a 2012 stx550 which recently started going into limp mode when towing trailer with 600kg utv on it so not overly heavy. Just preceding the limp mode there was a pinking type noise around the turbo and limp mode set in. On investigation the code showed that it was turbo solenoid was faulty so replaced it. Next trip it goes into limp mode again but this time I didnt notice the pinking noise and it wasnt as severe going into limp mode as on previous occasions. There is no codes showing on the scanner and my mechanic has looked at it and cant understand why it is faulting and ideas would be greatly appreciated. It doesnt do this when not towing trailer. My mechanic who is the dealer I got the car of is now saying well it has done 200 000 kms so its to be expected but I dont agree

 

[Old.Tony]

I don't agree either. Mine's done over 380,000km and purrs.

Unexplained limp mode might be the SCV. The very first thing you'd try is throw a bottle of good injector cleaner into the tank and see if it improves. Chances are the SCV is just a little dirty.

If that doesn't improve things, you could examine the SCV (it's on the pump), I don't often hear of V9X SCVs having issues but with the cars getting older it's possible. If you pull the SCV out and it has scoring on it, it's probably the culprit. Another test you could try is driving around with the fuel cap a little loose, if the problem has gone it's almost definitely the SCV.

 

[Fivefivezero]

Also check the hoses from turbo to intake.
My 550 was going into limp for a while usually when punching it up hill(not towing), finally found 2 splits in the hose from underneath, on the intercooler(cold side)

 

[bringthenav]

I was limp moding for a while.
When pushing the accel a bit too hard. 300k on clock.

No longer limp mode at all.

Mind you after diagnostically cleaning the motor air intake, and everything under the sun..
trying to clear carbon, after a dusty dirty that foul air filter that came with it.. it wasnt running so well under load, so i did lots of servicing & fuel treatments and oil change & then i noticed i had both cold & hot pipe clamps that were a bit loose.

I tightened and replaced every clamp & there's no more limp modes.

Check all your clamps everywhere,
Even that hot pipe baffle, seems to be a spot that likes to leak boost.

I removed that junk and just put a piece of steel exhaust pipe i had laying about instead & it is holding.

Later i will install a stainless hotpipe i bought & will be even surer that ot isnt leaking.

So :
*Clamps could be loose
*Soft Hot pipe could be expanding under boost/load !!
*Baffle in front hotpipe might be leaking boost too

I also did a catch can at same time.. which would be helping dramatically with blowby..
I had a small puddle of black oil in my turbo pipe in front of the impeller.
This would just be a bonus that probably is a good mod when your kms are higher & your towing..
Alot of oil and oil vapour would be polluting your system.

I firmly think my limp mode was just from leaking boost

 

[viclord]

While I was doing my weekly routine of checking fluids on my D40 Navara, I could see some leaking black oil in the hot pipe at the top of it where the spring-style clamps are, so I cleaned it up and will check again in a few days but most likely I will be replacing the rubber pipe for a steel one.

Also, I could see some small burned areas on the bonnet protector/carpet:

 

[viclord]

While I was doing my weekly routine of checking fluids on my D40 Navara, I could see some leaking black oil in the hot pipe at the top of it where the spring-style clamps are, so I cleaned it up and will check again in a few days but most likely I will be replacing the rubber pipe for a steel one.

Also, I could see some small burned areas on the bonnet protector/carpet which I understand is another sign that the pipe is expanding too much:

 

[bringthenav]

Hello.


BAFFLE !!

Currently not limping at all & can slam foot to the floor up to 5000rpm every gear..

Just a week ago though i was previously clear of limps for a minute by tightening every boost clamp in the whole bay.

I had been limping when applying more than half pedal, randomly.

That baffles a bitch that likes to leak boost. I noticed some oily residue there a year ago, cleaned it off, tightened the clamps up a bit more.

The oily residue remained.
I read it leaks boost so i replaced it with a steel piece of mild steel i had laying around.

That too eventually leaked boost.
Limp mode. 25 times ive had the limp mode in past 10 months .

The areas under so much pressure.

I now have the steel pipe triple clamped on both ends.

Zero limp mode !!!!!!!!!!
Your welcome

 

[viclord]

I have replaced the hot pipe with a steel one and so happy with the performance. I definitely not losing power anymore.

 

[Ron Micallef]

Do you have a part number, as I am having trouble locating this on their website.......Thanks

 

[viclord]

Do you have a part number, as I am having trouble locating this on their website.......Thanks

I bought it from 4x4 Mods Australia website because of cheaper delivery

The part number on their website is D40NAV-HOT-11ON-STD

Keep in mind that I ordered mine for my 2013 D40 Navara