Fixing the overboost issues with the MN 2.5HP

[Hugebettyswollocks]

The slight rev on clutching has all started since this problem occured, fuel filter should have been done last year , about 12k kms ago.

Been through and checked all the hoses and everything is fine.

Iam just going to have to get the mechanic to actually drive it this time and experience it for himself, instead of just a quick rev on the garage floor..

[Cowboy Dave]

12,000 is a fair while on the filter. Matter for you but I'd change it just in case unless you have a service due where that will happen anyway.

[biggibbo]

I would not be leaning toward overboost. I would change the fuel filter first and hit the MAF sensor with some cleaner and give it a shot of 2T in the next fill up. If that don't work, I'd be looking at carbon build up in the manifolds. Sounds like it is starving for fuel or air.

[ag9111]

A per gibbo I would suggest fuel starvation.
I had a fuel filter last less than 500km after picking up a loadof crap fuel when starting my last holiday

[rob2263]

Trying to track down one of these for my MN. Does anyone know who sells them or where best to search.
Cheers

[L200Shogun]

Trying to track down one of these for my MN. Does anyone know who sells them or where best to search.
Cheers

Dawes Valve?

[Tony]

I have them, my company "SPV Industries" is a silent sponsor of NTN (tony@spvindustries.com) but a long waiting list for the genuine HD hybrid dawes valve as we like to develop each one as a kit prior to release (test and calibrate). We do not supply the cheap and nasty Chinese knock offs.

[rob2263]

Hi Tony, I sent you a PM and an email but didn't hear back from you. If you can get back to me so I can give you my details and requirement.
Cheers

[Tony]

Sorry, think is in my urgent pending list. I'm away till Wednesday so will try and work through it after that.

[hvac guy]

Me to dont forget

[rob2263]

Hi Tony, not sure if you are getting my messages or not, can you let me know if you are getting them.
Thanks
Rob

[biggibbo]

Hi Tony, not sure if you are getting my messages or not, can you let me know if you are getting them.
Thanks
Rob

Email him mate - tony@spvindustries.com

He get tons of private messages.

[Earthmover]

Hey guys,
I've been having problems with overboost on my 2012 MN manual, I've got a scotts rods 3" system(with cat and muffler) on it with a DP Chip, snorkel, k&n filter.
Has anyone had any luck eliminating the issue by going back to a smaller dump pipe and then into the 3" system?, if so what sizes have people tried?
Very frustrating, you spend all this money to get better performance but then have to baby it up the hills when you need the power the most, I tow a 1.6 tonne fuel trailer and have had some seriously scary experiences overtaking trucks on hills...
I'm at the point of putting the stock system back in if I can't find a permanent fix, so any advice is greatly appreciated.
Cheers.

[biggibbo]

Will still do it with the stock exhaust as well, just not as often. Just need to learn to drive around it. Backing off on the throttle a few times up hills seems to work.

[srb]

Make sure you let Scott's Rods know the trouble you are having, and explain how it has nearly killed you! They seem to think the issue doesn't exist with their cat systems.

There are ways to minimise the chance of it happening, clamp map voltage and use a dawes valve. In the meantime just pulse your foot off throttle for a split second every 30sec when you're hard up it, this will stop it limping.

[scumbag]

where would you find one of these voltage clamps?
would it be possible to use a combination of the voltage clamp and a dawes valve set up to run more boost?
25-30psi might put the wind up it abit?

[Cowboy Dave]

Talk to Tony. He's your one stop shop with this stuff.

[Earthmover]

Make sure you let Scott's Rods know the trouble you are having, and explain how it has nearly killed you! They seem to think the issue doesn't exist with their cat systems.

There are ways to minimise the chance of it happening, clamp map voltage and use a dawes valve. In the meantime just pulse your foot off throttle for a split second every 30sec when you're hard up it, this will stop it limping.

Will still do it with the stock exhaust as well, just not as often. Just need to learn to drive around it. Backing off on the throttle a few times up hills seems to work.

Thanks fellas, yeah I've been feathering the throttle up hills but the anticipation of "is it going to happen?" is worse than climbing over an electric fence
I never had it happen when it was stock and I used to pull up long hills flat foot in fourth gear.
I might have to look into the dawes valve again, I sent Tony an email a couple of months ago but didn't hear back, I'll have to try again and see if I can get on the waiting list

[Jacks Home]

Come across this from Taipan exhaust website which talks about some vehicles, including Triton 2.5 litre, needing a 2.5 " dump pipe with their 3" system to prevent overboost. Bought the 3" Rods exhaust and I'm now reluctant to fit it.
http://taipanxp.com.au/the-taipanxp-difference/

[NowForThe5th]

Yep. Bigger is not better.

[Redneck198033]

wow how dangerous is this fault, I had my first case of this issue while hauling my 1.5tonne van. I have hauled this van heaps of times before putting on the fuel saving chip & exhaust.
I think this might be the first time after installing my roo's system exhaust & chip 12 months ago.

I was climbing fairly steep hill, in third, almost at the top when all hell broke loose, had NFI what was going on, engine light & ASC lights came on, I guess this is the limp mode.

So is there a real fix for this issue yet?

Mitsi was useless they said put the old exhaust back on.
Roo' system are useless as, well the fella on the other end of did not want to help or assist in anyway. great support.

also my stats are 2010 MN GLX-R, new motor after it cooked at 60k now at 70k. long range tank, 265-65-17 on stock rims, front bar with winch, rear bar, extra final filter fuel manager 2 micron, catch can for rocker cover oil, tough dog suspension, canopy.

A fix for this overboost besides putting the old exhaust back would be good.

Also I have cleaned the MAF, this seemed to give me more time before the fault came back e.g. 15 sec flat in third forth before issue, I have also ordered a new final filter.

CHEERS

Mick

[snakesoup]

from what I have heard here on the forum mate is that it's possible to drive accordingly to avoid this happening, something to do with backing it off for just a sec and then getting back on the gas to resume the climb up the hill, so flat to the boards for 20 secs then blip the throttle then back on the gas etc.. hopefully some one that does this and can chime in and tell you what they do
think it might have been SRB that was talking about this ...good luck with it

[coughy]

yes that is correct in throttle technic
i find it is a bit random in its happening sometimes take longer than other's
im still working to find out where the cut out is in this as are a couple of others in the platinum section of the forums

[Redneck198033]

Surely this is not a real fix, throttle backing off then back on, the ECU should be picking this up & change the turbo pressures to suit.

Does anyone know what the vacuum pressures are when the valve fully closed the turbo vaines?

Does anyone know what the PSI turbo pressures should be at max load, this must change depending on the RPM's?

I'm taking my rig into a Diesel mech. to look over it, he is looking to take the chip out, because he is a steinbauer rep & believes his product is much better.

The roo chip is working fine so far, fuel savings are good & power is good, I have not had any issues till now with me towing my van.

[Cowboy Dave]

It's the exhaust. You can't blame mitsy for something you've caused by putting too big an exhaust on it. It's just a shame the exhaust retailers aren't more knowledgeable on the product and what it will do to these cars.