Mazda Rotary Club

General => General Technical => Topic started by: goggs78 on May 22, 2007, 07:55:50 PM

Title: FC turbo 2 boost problem
Post by: goggs78 on May 22, 2007, 07:55:50 PM
I have no boost at all, the guage goes up to zero (sometimes just past it) and gives up, it\'s not the guage because there is definete lack of power. I think it\'s a split pipe somewhere unless someone has another possible cause. To make my hunting eaiser, how many pipes are the coming of the turbo? and which ones are likely to fail. Any help will be much appreciated, cheers.

:eek: This smiley looked funny so I put it in.
Title: FC turbo 2 boost problem
Post by: drutin on May 22, 2007, 09:46:57 PM
howzit :)

check your oil level too :)

the pipes to check would be firstly your intake pipes to the turbo from the airflow meter to the front of turbo they usually crack next to the turbo, because its airflow metered they run crap
then check the rubber hose coming from the outlet of the turbo snail to the plastic or alloy (depending on series ie 4/5) then check the rubber hose on the other side of join to the intercooler

usually the intake pipe is crack or the outlet rubber hose or the pipe to intercooler blows off

hope helps
let know what you find :)

later
glen
Title: FC turbo 2 boost problem
Post by: goggs78 on May 22, 2007, 10:01:33 PM
cool, will hopefully have a look tomorrow, I\'ll let you know.
Title: FC turbo 2 boost problem
Post by: goggs78 on May 25, 2007, 11:46:13 PM
Had a bit of a look, not much time to do anything major, checked all the hoses, they seemed fine, then I checked the wastgate arm, which seemed like it wasnt on the pin properly, so I wedged it back into place with a REALLY big screwdriver. not 100% sure if it was out of line enough to cause no boost, but when I get paid I will test drive it and see if it worked (i\'m poor this month). I\'ll keep you posted.
Title: FC turbo 2 boost problem
Post by: Brett on May 26, 2007, 10:17:52 AM
I think its a fairly common fault for the pin to drop out of the waste gate arm - Have a feeling Grinder found his arm hanging off....
Title: FC turbo 2 boost problem
Post by: goggs78 on June 03, 2007, 08:31:37 PM
I seem to have more boost now, but I dont think I quite have enough, It goes up to where it says x10 on the guage, is this right?
Title: FC turbo 2 boost problem
Post by: goggs78 on June 10, 2007, 10:42:57 PM
pleeeease help
Title: FC turbo 2 boost problem
Post by: Prof on June 10, 2007, 11:31:50 PM
You still having boost issues ?
 
It could be the boost solenoid or the piping leading to it.  There is a hose that joins up with the small pipe that comes off the compressor out side (the vertical pipe coming up from the turbo and going to the intercooler) and goes to the wastegate.  It\'s job is to blead off some of the air to the wastegate, delaying the opening till a higher pressure is reached.
 
If this pipe is blocked or the solenoid is not woking, then the turbo will only make about 5psi before the wastegate opens.  With the boost solenoid working, it should reach 8+. (you will only get top boost in the higher gears - 3rd, 4th and 5th)
 
The solenoid itself is normally located on the oil filler neck unless it\'s been moved.
Title: FC turbo 2 boost problem
Post by: goggs78 on June 11, 2007, 10:02:31 PM
Mine goes halfway then stops. sounds like the solenoid is the problem, I think I found it but I\'m not sure, can anyone post a piccie of it and tell me how to test it cheers.
Title: FC turbo 2 boost problem
Post by: Prof on June 11, 2007, 11:32:30 PM
Heres a pic from the service manual.
 
The solenoid is fed with a pulsing signal from the ECU, so a bit difficult to measure with a meter.
 
However, if you disconnect the plug from it, you can measure the resistance of the coil.  It should be about 50 ohms.  If you then apply 12v across it, you should here it \'tick\'.
 
Another test you can do, is to detach the vacuum pipe that comes from the turbo to the solenoid, and block the hose with a bolt or something similar.  Then test drive and see if you make the same boost levels.  If you do, then the solenoid is faulty and not opening.
 
Good luck.:Thumbs-up
Title: FC turbo 2 boost problem
Post by: goggs78 on June 11, 2007, 11:54:48 PM
ok, cheers for your help so far, I will try this tomorrow and let you know.
Title: FC turbo 2 boost problem
Post by: Brett on June 12, 2007, 08:38:20 AM
Bear in mind 90% of TII boost guages dont work properly - none of mine ever went beyond the half way point, so you may be making maximum boost and not realise it.  I\'d hook up another guage to be sure.
Title: FC turbo 2 boost problem
Post by: goggs78 on June 12, 2007, 07:10:42 PM
the car definetly feels underpowered, either that or I have extreme paranoia!
Title: FC turbo 2 boost problem
Post by: goggs78 on June 12, 2007, 08:27:14 PM
neither of the two pipes go to the turbo, they both loop back up and connect into a block with 4 different colour connectors on it.
Title: FC turbo 2 boost problem
Post by: goggs78 on June 12, 2007, 10:08:13 PM
I took it out for a run today, it got more boost, but when it got to 3/4s (as high as it went) the boost started droping off. It seems to have good and bad days and I really cant figure out what\'s causing it.
Title: FC turbo 2 boost problem
Post by: goggs78 on June 13, 2007, 08:42:49 PM
Quote from: BrettBear in mind 90% of TII boost guages dont work properly - none of mine ever went beyond the half way point, so you may be making maximum boost and not realise it.  I\'d hook up another guage to be sure.
where\'s the best place to do this?
Title: FC turbo 2 boost problem
Post by: grinder on June 13, 2007, 08:59:40 PM
look on the drivers side shock tower and there is a little box with a pipe running out of it - i spiked my boost gauge from this point

if you follow the pipe it will split off - so just add another T piece in one of the lines

i then mounted the boost gauge in a pod by the idiot lights in the centre top of the dash and picked up the illumination feed from the back of the cig lighter

hope this helps

Stu

( you can see the boost gauge right at the top of the pic )
Title: FC turbo 2 boost problem
Post by: goggs78 on June 17, 2007, 11:07:34 PM
turned out it was a dodgy guage after all that. thanks for your guys, very much appreciated
Title: FC turbo 2 boost problem
Post by: Brett on June 18, 2007, 10:02:44 AM
No worries - I spent about a month checking and rechecking everything to find out the guage was duff! :Thumbs-up