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Discussion Starter · #1 ·
Have had the td04 in now for about a month (been taking it real easy on it to make sure didn't have any other problems first) and have found that the turbo does seem to boost at a higher rpm then my stock t25 did, but I am only get about 7psi in each gear (lower in 1st and 2nd around 5psi). I have not done anything to the ecu yet and still waiting to get the dp but can't figure out why the dramatic loss in boost???
 

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Do you have a MBC? When I went from T25 to TDO4 I had to turn the MBC way up just to match what I was running befor the swop, no tune as well then. If you don't have a MBC then I would say you have a leaky delivery system. So if you removed piping to do the swap check there first. good luck

JT:)
 

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Check your BPC fuse....
Had that problem when i switched from t25 to td04....

was running like that for a week....then figured it was the fuse when i tried 3 different bpc.
 

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Discussion Starter · #4 ·
Check your BPC fuse....
Had that problem when i switched from t25 to td04....

was running like that for a week....then figured it was the fuse when i tried 3 different bpc.
Where is this BPC fuse? I looked around and nothing, went online to look it up and found where an APC fuse goes under the hood, but in my car did not have a fuse in the spot and nothing there if you try to put one in (#13 7.5 under engine bay).

I've also been checking all tubes and piping for any leaks and nothing yet;oops:

Any more ideas would be great...Thanks guys!
 

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checking for boost leaks

A good way i have found to look for is a boost leak is to:

1st start your car let it run at idle.
2nd take a small propane torch open the flow valve on the torch so the gas starts to flow out.
3rd take it along all your seals such as gaskets and hose linkages.
4th if you have a leak when you go over it with the torch it will suck in the the gas and you should hear your engine rev.
5th hopefully this will help you find a leak that's if you have one.
 

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Ooo, is urs a 93 or ng900?? it might be a different set up...but i dunno
i know i had a fuse there and it was broken, then i changed it with one of the spares and im good to go!

u should still have a fuse tho....wierd?

have u check the bpc??? it could be sticking....

thats it for now, unless a boost leak...but u would hear that!
 

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A good way i have found to look for is a boost leak is to:

1st start your car let it run at idle.
2nd take a small propane torch open the flow valve on the torch so the gas starts to flow out.
3rd take it along all your seals such as gaskets and hose linkages.
4th if you have a leak when you go over it with the torch it will suck in the the gas and you should hear your engine rev.
5th hopefully this will help you find a leak that's if you have one.
Cept with a T25 the intake manifold is atmosphere + at idle, just check your BOV.
-Cm
 

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Have had the td04 in now for about a month (been taking it real easy on it to make sure didn't have any other problems first) and have found that the turbo does seem to boost at a higher rpm then my stock t25 did, but I am only get about 7psi in each gear (lower in 1st and 2nd around 5psi). I have not done anything to the ecu yet and still waiting to get the dp but can't figure out why the dramatic loss in boost???
In your sig it says 01 So that makes it a airmass based t7 system. Airmass is calculated from flow volume and density(pressure+temperature) Your new turbo moves the same airmass with less pressure required. At same pressure it will move more airmass. So the ecu in its quest to reach target airmass will use less pressure to do so.
 
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