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Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Tue, 10 Aug 2010 10:00 +0000
by Monster Rides
Hey Fellas,

A good mate of mine is having all sorts of issues with his Hilux D4D going into limp home mode.

Here is a basic rundown of symptoms, and whats been done so far with no success to fix it, as cut and pasted from a email:

"Talking about the daily limp mode scenario of the Lux

It’s done it for about 2 years but a lot less maybe every 3 months back then

Being auto the Lux will go into limp mode at different speeds rev range and even gears!

It will re-start once key has been turned off and restarted 20 seconds later!


The Spider performance module and exhaust was done 9 months ago but its only been last 2 months that the almost daily limp mode had been happening.
Exhaust is 2.5”


Our scanner found the fault code P1251 and its even been to a 4wd dyno testing place which has also failed to determine problem which sort of tells me its more electrical

That fault code says stepper motor but apparently can be caused by a few other things,

Turbo has been removed, Pressure sensor switch has been replaced, MAF sensor has been cleaned, Negative contact was loose on body now tightened,


I was about to get another turbo control board but thought I’d source an auto elec instead of replacing the “maybes”

Anyway if there’s anyone who knows anything which could help, I’d appreciate it


Cheers"



So there you have it.

Limp home mode was happening on the stock vehicle, then more frequently with the chip and exhaust.... now daily.

If anyone might shed some light on this issue it would be handy.
Toyota has been no help, and yes... the truck is out of warranty.




Cheers
Matt

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Tue, 10 Aug 2010 11:06 +0000
by toyboata
just lifted this from another forum....looks like it should provide an answer to ur problem
http://www.4wdaction.com.au/forum/showt ... hp?t=73628

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Wed, 11 Aug 2010 7:07 +0000
by crosssport
If it has no cat converter it will cause boost spike which then makes engine go into limp mode. Had a patrol 3 litre doing the same thing. He had an exhaust made up with no cat and that's what happened. If this is the case either fit a high flow cat 100 or 200 cells, or I can supply a boost cut unit which allows you to run more boost without causing limp mode issues.

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Wed, 11 Aug 2010 8:04 +0000
by jap
On a diesel I would recommend a 100cpi cat to keep restriction at a minimum.
F**k it, go the boost cut defender too :twisted:

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Wed, 11 Aug 2010 12:47 +0000
by GreenHilux Guy
get your friend to call Kerry at Taipan XP exhausts. He has developed a custom relay and fuses which bypass toyota's sensativity to turbo PSI.

This relay wasn't available for me when I was having problems with my old green ute but after fitting a digitial Turbo Boost gauge I could prevent it by happeneing by letting it go higher then 19 - 20 psi for exteneded periods. He might also consider an air/oil seperator which could prevent build up which is dirtying some of the sensors.

Is he running a OEM air filter or an oil based one? This apparently is where my problems started...

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Wed, 11 Aug 2010 4:13 +0000
by Monster Rides
Thanks Guys,

Much appreciated, I'll pass on the info and keep you informed of progress.

He mentioned that the exhaust has a catalytic converter, so scrap that idea.
But I might suggest he goes back to a stock exhaust and see if that fixes the problem.

Don't suppose anyone in the Melbourne area has a stock exhaust lying around?



Cheers
Matt

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Wed, 11 Aug 2010 6:39 +0000
by Hilux Max
yeah, i might have......

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mode

PostPosted: Wed, 11 Aug 2010 7:43 +0000
by Monster Rides
mmaaxx wrote:yeah, i might have......


Legend.

Thanks Mate

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Tue, 07 Sep 2010 3:20 +0000
by smaca
Any status on the progress of this problem?

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Wed, 08 Sep 2010 12:42 +0000
by Husky77
Out of curiosity, is his O2 sensor functioning properly? Had a similar problem on a different car several years back, my oxygen sensor somehow developed a bad earth along the negative wire which caused all sorts of issues.. took over a year to trace it back to that but was good as gold after we fixed it. Just a thought..
Hope he tracks it down i know how frustrating these things can be! :evil:

Craig

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Wed, 08 Sep 2010 7:31 +0000
by smaca
I have his exact problem and have tried everything!!! Been over a year now and I still haven't resolved it. Toyota has no effing idea, they just charge by the hour and keep on telling me they need more time!

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Mon, 13 Sep 2010 6:41 +0000
by TuffluxOffroad
Hey Guys

This is my first post, The Lux with the Limp mode problem is mine, Matty has been helping me out with a post or two which I appreciate maaate!
Anyway I still have the same problem with the fault P1251 and going into linp mode intermittantly, the problem isnt happening as often so I think were on the right track, after spending big dollars and a lot of different input
Ive had it on the dyno where Toyota sends its jobs to, its had a ptressure sensor replaced the turbo removed cleaned adjusted via veins and the gate, Its been to my auto elec who found a loose connection on the stepper motor and a loose earth wire, Ive removed the MAF sensor and scanned it which came up a totally different fault code, cleaned the sensor anyway, I cracked the shits and swapped the Stepper motor from the other hilux in our workshop { yeh he cried} and its still doing it but not as often,
Any other Guys had any luck?

Cheers Guy
Tufflux Offroad

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Thu, 23 Sep 2010 1:58 +0000
by smaca
I changed the EGR assembly hoping that it would fix the problem, but i'm still getting the error.

I give up!

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Mon, 27 Sep 2010 6:31 +0000
by 269LUX
Hey mate it sounds like a problem i had which was carbon build up in the turbo. Toyota told me to throw the turbo over my shoulder and get a new one! so i took it to a turbo specialist. he took it apart cleaned it out and it hasnt happened since mate. hope this helps although it sounds like you may have already cleaned out the turbo ay? I feel your pain F#%ck toyota service i say!

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Tue, 28 Sep 2010 11:04 +0000
by smaca
Wish it was that easy. I replaced it with a new turbo (as per Toyota's advice) and it's still doing it.
Now I have a spare perfectly good turbo lying around!!!
I agree with you.....F#%ck Toyota service, they are a rip off

Resolution to D4D Error Code P1251 & Limp Home Mod

PostPosted: Tue, 05 Oct 2010 12:11 +0000
by Hilux Max
269LUX wrote:Hey mate it sounds like a problem i had which was carbon build up in the turbo. Toyota told me to throw the turbo over my shoulder and get a new one! so i took it to a turbo specialist. he took it apart cleaned it out and it hasnt happened since mate. hope this helps although it sounds like you may have already cleaned out the turbo ay? I feel your pain F#%ck toyota service i say!



you are dead on he money here mate! I have finally found what the cause is and what you said is 200% correct, not mentioning who the sources were but pretty much straight from the horses mouth!

This concern with your mates Hilux can be attributed to carbon build up or even rust forming on the turbo internal variable vanes.
What happens is that the turbo vanes are trying to move a certain way upon deceleration and can't move quick enough and then the ECU picks it as an overboost and logs the code.
If he has an Intelligent Tester you can do an active test on the stepper motor about ten times and it may loosen the vanes off a bit but there's no guarantee.
The end result could be a new turbo?


stepper motor-turbo.JPG


so bottom line is a carbon or rust build up on the turbo vanes....how that happens? not sure, bad fuel, water in fuel?

hope this helps.

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Wed, 06 Oct 2010 6:51 +0000
by smaca
I replaced mine with a new turbo and i am still getting the problem. Mine goes into limp mode when I accelerate not when decelerating.

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Wed, 06 Oct 2010 7:52 +0000
by Hilux Max
smaca wrote:I replaced mine with a new turbo and i am still getting the problem. Mine goes into limp mode when I accelerate not when decelerating.



It seems the problem is with the ECU registering an Overboost....if you have replaced the turbo with a new one then something else in the system must be triggering an overboost signal.

have you fitted any other mods to your hilux that may be causing this? powerchip/exhaust etc?

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Wed, 06 Oct 2010 8:08 +0000
by smaca
It used to have a Humex 3inch exhaust but I removed it because Toyota told me that it was causing the problem. I replaced it with the factory exhaust but still the same problem. Toyota now scratching their heads! Only other extra it has is a Safari snorkle, no powerchips.

Re: Tech Help Please? - D4D Error Code P1251 & Limp Home Mod

PostPosted: Wed, 06 Oct 2010 8:10 +0000
by Hilux Max
keep us updated with whatever they find....I know, it must be heartbreaking and ball breaking...good luck.