twin turbo probs

[gavink]

Hi....

Ive got a few boost problems with my rex (95 FD)..

The problem im getting is intermittantly the boost takes a long time to build up...example...

Ill be cruising along at 60 mph in fifth then floor it and the boost will shoot to .8 bar (runnung base map on apexi ecu)..thats fine no problems there..

Then ill be cruising again at 60mph and floor it but this time the boost takes along time to get to .8 bar (just creeps up on the commander display) but WILL get there over approx a 10 second period..and the car does feel flat.

Ive ran a boost check and get .8 .7 .8 so thats ok.

Now the problem is intermittant so i dont know how im going to find it....any one got any ideas
Ive checked the obvious vac lines etc - all ok (would be there all the time anyway)

thanks

gavin...

[BlitzBoy]

boost leak somewhere, check your intercooler piping rubber coupling check for splits, jubilee clips may hide the splits, when cold the splits dont really open up hence u see no boost problem to begin with, as the car warms up the spilts open up more hence your slow build up of boost.

[Fish]

Could also be a pipe collapsing.

Fish

[gavink]

Originally posted by BlitzBoy
boost leak somewhere, check your intercooler piping rubber coupling check for splits, jubilee clips may hide the splits, when cold the splits dont really open up hence u see no boost problem to begin with, as the car warms up the spilts open up more hence your slow build up of boost.

Thankyou for the reply..

All hoses are ok,i had them all off when checking the vac pipes..

It doesnt matter if the engine is cold or not, one min it will boost fine one min it wont...Wish i had the money to go single !!!:rolleyes:

gavin..

[BlitzBoy]

well not the hoses themselves, the actual rubber couplings which connect the twin turbo pack to the crossover tube and the rubber couplings that connect the boost hoses to the intercooler, take these off completely and inspect them the splits are sometimes hard to spot.

Other then that all I can think off you may have a kanckered wastgate actuator

[gavink]

Thankyou for the replys

IVE COME TO THE CONCLUSION THAT I DONT HAVE A PROBLEM...

I got told to read through this on another website and it describes what i thought to be a problem as normal..

this is what it says

Ok, now for a couple of notes. The turbo system goes into twin mode when you pass the transition point (about 4500 rpm at WOT, later for partial throttle). It does not return to single mode until you go below 3000 rpm. So, if you go past the transition and then coast down to 3100 rpm or so and floor it again, it will be a little slow building boost because both turbos are still on-line. It is supposed to work that way.

Now that is exactly what im getting...Little did i know that once i go past 4500 with WOT that the car then stays in twin until i drop below 3000 rpm....

Live and learn



gavin..

[TonyBlair]

So glad I spotted this thread. I don\'t think I have that much of a problem anymore; http://www.mazdarotaryclub.com/forums/showthread.php?s=&threadid=14648  

I\'m still losing boost from somewhere though. My boost gauge never goes above 0.6 bar :mad:

Cheers
Jon