Help Boosting Problems

[Sooperkent]

Alright guys

Dont really know where to start here

Bought an FD a week ago and we are partaking in the long process of fixing all the small niggles

When i give it abit of "lead foot" in second gear it revs right up and it feels like both turbos kick in about 0.7bar boost but once i shift to 3rd or 4th its like it hits the brakes - its a noticeable pulling back of the car and it looks like mega vaccuum on the boost gauge (which would suggest the throttle body is closed)

I dont know if this is fuel cut/Boost leak/wastegate not opening or maybe solonoids?

Can anyone give me any heads up please?
Or even what to search for in the forums? lol

[Sooperkent]

What are the symptoms of a boost leak
And the symptoms of fuel cut?

[neil_jdmr]

If it boosts up ok in second gear to 0.7 bar then it\'s not a Boost leak. From your description it\'s set up to run non sequential ( both turbos at once, boost from 3k). Fuel cut feels like you have stomped on the brakes hard,

To help more info is needed mate,
Standard ecu?
Full exhaust, filters etc
Cat still there
Turbo pattern etc etc

[Sooperkent]

Ok, it seems as though im hitting fuel cut then - feels like hitting brakes hard.

Standard ECU - Cat back exhasut (came this way) i think both the cat and precat are still there.
Stock air filter (which needs changing)
Also as far as im aware this is still the twins you can feel the second tubby kick in, in second gear
Turbo Pattern? Sorry mate can you explain this one?

Could this be Fuel cut due to boost creep? and if so a manual boost controller might sort it?

[Sooperkent]

Right chaps - did some more testing.
Removed the pipe with the pill in it and put in a straight unrestrictive pipe so that i am running only .5bar boost while trying to find this issue.

Seems to me like the second turbo isnt coming on, Hits fuel cut in second gear at about 6k revs and my boost controller isnt showing any spikes or anything

Floored it in 1st and it revs to redline but feels like 2nd turbo in non existant

4th bogs down at 50mph and hits fuel cut and 5th at 55mph - really am stumped as where to go from this

Any extra advice needed?
Now if its a case of the second turbo not coming on - then why am i hitting fuel cut?

[clive]

Do you know if the car is non sequential or still sequential, if its sequential it will feel like fuel cut at the point where it tries to bring the second turbo in and can\'t  ?

Does it have any mods ?

Are you able to go back and ask the seller if he had these problems before you bought the car ?

[neil_jdmr]

If you are now only boosting to 0.5 bar then the second will not engage as your boost is too low for the solenoids controlling the secondary transition to operate. You say your boost controller is OK but with a Boost controller plumbed you wouldn\'t be using the pills mate.

Again more info on your set up is required for us to help.please list your mods etc,

[neil_jdmr]

Where does it build boost from 1800rpm or 3k, are you on a standard ecu are the first questions?

[boosted]

mine was non sequential and ran front turbo outlet to actuator pipe so only actuator spring to control boost...0.5 bar and would boost all day long....as soon as i plumb it for 0.7 bar it would fuel cut in 2nd about 4-5 K...what happens on half throttle? and 3/4 throttle?..i could get mine to redline with right foot regulation....in the end boost controller and apexi with remap.
Where are you measuring boost from? UIM?

Plumb from front turbo out connector to Wastegate actuator ...there 2 actuators there 1 is precontrol and the other wastgate...that will take out the solenoid valve and limit boost to 0.5 bar. non seq or seq this should boost all day long and prove whether you have a 2nd turbo issue.

need to be very careful....as rotarys do not like detonation and you risk fracturing you apex seals.

[boosted]

This is non seq? or we dont know?

[Sooperkent]

Just so we are all on the same page here - When i bought the car the seller told us it was all standard apart from the Cat back exhaust

I have a boost controller but it is not fitted yet. And yes i am measuring the boost off of the UIM

we have to assume that the car is running sequential twins.

I only just removed the pipe with pill in it today to try and reduce any boost spiking although as iv read here its not ideal as the second turbo wont engage?

Before we removed the pill it was showing the same symptoms - what feels like someone slamming on the brakes while revving in any given gear (foot 3/4 or more down)

I can take it to redline if i rev up slowly and the boost doesn\'t build very much

In 2nd gear im sure the boost starts to build at 2.5kish? (id need to double check this)
and then hits the fuel cut at 6k revs while boost is at 0.5without pill or 0.7 when the pill was in.

So first off i should be eliminating the second turbo to see if its still cutting fuel? I cant make too much sense of "Plumb from front turbo out connector to Wastegate actuator" Boosted  Is there already a vacuum hose on the front turbo connector?
i know the wastegate actuator is the one on top.

[neil_jdmr]

We still don\'t know mate, it sounds like it and if so I\'ll part out as seq is my limited field ;-)

[boosted]

Forget that mate..only works if you non seq...

[neil_jdmr]

What you say about hitting the brakes sounds like fuel cit tbh,I will also guess it\'s standard ecu then. Firstly put the pill pipe back in So it boosts to 0.7 on the primary and next Check the plugs and Change the fuel filter. Fuel cut usually is only active if the standard ecu detects excessive boost which you don\'t seem to have so I would check the pipes to the wastegate. Also have a read through fd3s.net and robinette site as they cover seq turbo probs very well

[Sooperkent]

I will put the pill back in and report back - on the plugs all im looking for is fouling? the pipes to the wastegate actuator were fine (checked when i removed the pill) had a look at the robinette site and unfortunately i dont have the tools to vacuum/pressure test solonoids.

Really am stuck here - not too sure what to do next