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Hi guys,
I have a 2004 3lt DI. I have done some mods. Blanking plate EGR, Dawes and needle valve, catch can, upgrade inter cooler, HPD MAF housing and air box lid, k&n air filter, 3" exhaust.
Max psi is at 15psi trying to eliminate boost.
Have an extra MAF sensor from another car that has no faults in other vehicle but my patrol still goes in to limp.
Need help to fix, driving me crazy.
HELP!!!
Scott
 

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My sons car went into limp mode. The computer showed fault as low boost. Turned out to be a blocked fuel filter. This was telling the ecu low fuel delivery so ecu was turning down boost.
Is your check engine light on?
 

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Hi Covo71, it seems odd that you are still getting the limp with the larger HPD MAF housing. The idea of this housing is to lower the MAF voltage because more air flow is passing than the MAF is reading. BUT this will initially make it feel guttless as the ECU is reading lower air flow and giving less fuel. I have a chip on mine and had it turned up to compensate. Now I also have a MAF voltage modifier so I can adjust the MAF to bring it back up slightly in the mid range.

So are you sure it is actually going to limp or fuel cut (does it accelerate well the do a sudden cut and drop power) or is it feeling generally sluggish right from start?


Have a read through this thread. The last few pages, I put up some details of the MAF voltage modifier that I am using - UAFC.
http://www.patrol4x4.com/forum/zd30...ory-snorkle-upgrade-feel-like-new-car-121322/
 

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Y2KGUII ZD Wgn
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Just to add to what Geordie says, limp mode is a combination of things, outright boost being the least significant, the map sensor only cares when you get into the mid to high 20's.

The main contender is MAF voltage, ie hit 3.88v under 2500rpm, 3.98v under 3000rom etc, etc, now this MAFv component also has to exist for a certain amount of time before the ECU calls time out, there is also a TPS component where it may happen at full throttle but not at 3/4 throttle.

The HPD MAF housing you have slows the speed of the air past the MAF giving the ECU a lower reading and therefore it puts in less fuel (something like 15 load points on a MAF voltage modifier that Geordie speaks of), so like Geordie I'm surprised that you have limp with that unit, I would be looking further afield, does your MIL light come on? are there any fault codes (see bible in ZD30DI archives for details on how to extract codes from the ECU if you don't have an ECUTalk)? With limp you won't get past 100k and the boost will drop to 10psi, lift you foot and all comes good until the scenario matches up again.

My 2 cents worth.
 
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