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I have tinkered with my Stag and brought the boost up 3psi by bypassing the bleed solenoid. The car ran great for a few day but has now seemed to have learnt it has no control over the boost level and fuel cuts my fun.

Has anyone worked out how to bypass this??? I noticed there is a boost sensor in adition to the MAF.....I figure I could bleed off air to the MAP but the MAF would still read the same.....

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I don't know how your boost cut works. Apparently on the R34 there is a sensor which cuts boost that can be fooled by a resistor in the circuit (its somewhere here on this site) but I don't know about your v6. I gues it depends on your long term plans. With the range of cars that you have i guess this is not going to be your drag car so you won't want to fork out for a Vipec ecu. I would suggest you build a DFA or buy a SAFC and fit that to give your engine some tunability.

It Fuel cuts, It seems to learn that it can't control boost. If i use snow mode its ok for a while then cuts again. How have you installed your boost controller?

All I have done so far is removed the std high-low valve. gives High boost all the time. instead of retarding it in low RPM.

did you unplug it? or leave it plugged in?

try the opposite of what you have now. i remember some nissans have a sook if you left them plugged in, or not plugged in when it wasnt being used..... might be worth a try!

It Fuel cuts, It seems to learn that it can't control boost. If i use snow mode its ok for a while then cuts again. How have you installed your boost controller?

All I have done so far is removed the std high-low valve. gives High boost all the time. instead of retarding it in low RPM.

In my car i have a apexi boost controller that controls the boost levels and i left the existing boost solenoid plugged in electrically but blocked off all the hoses.

  • 1 year later...
i know its a while back.

but did it make any difference?

If you loop off the boost solenoid and then run the line from the intake in to the suction pipe it will allow the boost level to build a lot higher.

Cheers

Andy

If you loop off the boost solenoid and then run the line from the intake in to the suction pipe it will allow the boost level to build a lot higher.

Cheers

Andy

Potentially catastrophic levels.. Id get a decent (read, doesn't max out at 15 or 20 psi) boost gauge to ensure youre not making too much if you do bypass the boost solenoid

Potentially catastrophic levels.. Id get a decent (read, doesn't max out at 15 or 20 psi) boost gauge to ensure youre not making too much if you do bypass the boost solenoid

With an Impul, yes... but not so with the Stock ECU.

If I loop the solenoid line and bypass it with the intake line, I max out at 1bar (where I hit the cut) whereas if I leave it plumbed as per stock, I hit around 1.3bar or so before cut

Edited by iamhe77

if youre taking the factory solenoid out of the equasion and have the boost line from the intake going down to the wastegate actuator, then youre running whatever the actuator is set at. if you remove the pipe to the actuator completely, then youre running whatever the turbo can do. ie, the wastegate will probably not open at all! dangerous for more than just your turbo.

just go EBC and make sure youre exactly where you want to be.

If you remove the pipe to the actuator completely, then youre running whatever the turbo can do. ie, the wastegate will probably not open at all! dangerous for more than just your turbo.

Only if the restrictor is removed from the solenoid line.

if there is no air going to the actuator due to the lack of vacuum pipe going to it, then it wont matter where the restrictor is :)

however, the restrictor is the first mod that should be done to all turbo cars :D

With an Impul, yes... but not so with the Stock ECU.

If I loop the solenoid line and bypass it with the intake line, I max out at 1bar (where I hit the cut) whereas if I leave it plumbed as per stock, I hit around 1.3bar or so before cut

yeh mine seems to climb to about 16-17psi before hitting cut. i dont know if its when i did the BB conversion, apparently the turbo guy likes to put washers on the Actuator flap to hold boost a little better..

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