Mazda Rotary Club

Cars by Model Type => 2nd generation RX-7's => Topic started by: TRex on February 23, 2005, 01:20:08 PM

Title: Boost cut?
Post by: TRex on February 23, 2005, 01:20:08 PM
Hi guys

 91 TII, stock/standard never modded.

 While cruising at or below 3K(rpm) in say 2nd /3rd gear then floor the throttle
BOOST...........then at 5K (rpm) massive surge for a second then boost continues........
 Does this in pratically all gears while changing up with full throttle!

 Is this fuel cut or a boost cut(over boost protection)???

 Any input welcome and ideas............ cures etc.....:god

 Ta.....
Title: Boost cut?
Post by: grinder on February 23, 2005, 02:45:34 PM
if its COMPLETELY stock with NO MODS at ALL ( as from factory )

my idea would be  .... bad earths

the yanks go on about it all the time - but its usually at about 3500RPM

not sure if its the same thing - but have a look at rx7club.com and find a thread relating to "hesatation"

that might help you

failing that - when you hit this power loss - whats the boost gauge showing ??

hope this points you in the right direction

stu

when you floor the throttle - are you litteratly banging it to the floor ??? i wonder if you are sending too much fuel thru - try flooring it but do it in a fluid montion - rather than just metal to metal

another thing to try - this is fun - drive at 80mph in 3rd - now turn the cruise control on , now slow down to about 3K RPM - but dont brake or press anything - leave it in 3rd - now reactivate cruise contol - this will force the car to accelerate up to 80mph as fast as it can ( very ammusing when the pedel just goes away from your foot ) - the car is now controlling how it accelerates - so does it still do it ?

ta

stu
Title: Boost cut?
Post by: TRex on February 24, 2005, 11:03:14 PM
Stu
 It seems mainly at or around 5K.... in all gears!

 Yes and only if it\'s full pedal to metal it happens, as if I go gradually on the gas or even almost close to the floor(80/90%) throttle..... seems ok.....????.......

 Another thing, when the engine is fairly cold/warm (just about warmed up), this symptom above is worse as after the spike it just hesitates(judders like) feels struggling for boost/power all the way up the revs!
 The warmer(hotter or correct operating temp) it gets, then it runs sweet............ But with the surge....

 Supprised no other takers on this......

 I\'m new to these cars/motors and just asking for any experience out there before I have a crack myself.

 Had a very similar snag with one of my Impreza\'s and it was the boost selenoid needed cleaning(had oil etc).  Common with them!

 Grinder thanks m8, I\'ll have a look on the rx7.com site...... haven\'t been there yet!
 
 Oh, I\'ll have a try at the cruise control test tomorrow, hopefully less snowy ****e roads then..........:reallymad

 Ta.
Title: Boost cut?
Post by: Gman on February 24, 2005, 11:07:32 PM
Not come across this myself, i would have a look on //www.teamfc3s.org/forum
Title: Boost cut?
Post by: TRex on February 24, 2005, 11:10:02 PM
Way heyyyyyyyy.

 :god :god :yes

 I believe I final fixed the demon........

 No not the car, for weeks I was having nightmares trying to post in the forums. I kept getting logged out instantly!!!
 
 Was ****ing me off big style!  E-mail to Glen in the club here and he directed me to \'V-Bullitin\' for the problem and seems many people have the same problem....
 So not being a IT major (can just hold my own) I had a dabble and hopefully it seems to be sorted now!    
 \'We\'ll see\'................. :evillaugh

 That reply above was made since yesterday and I have tried probably 30 + times trying to post the thing in the last 24 hrs!!!

 Dam.........

 Anyway cheers........ :cool
Title: Boost cut?
Post by: TRex on February 25, 2005, 10:09:23 PM
Ok, after playing around some more, it seems to be good ole boost protection............ "Fuel Cut".......

 Had to ratch up an old (proper)Boost gauge and an Air/Fuel mix meter I had laying about to confirm!

 So  THIS (http://www.hksusa.com/products/?id=683&rsku=4279)  baby is on it\'s way..... :D

 Rgds
Title: Boost cut?
Post by: grinder on February 28, 2005, 09:51:42 AM
you should have said - i have a spare FCD in the garage !

the blitz thiny i have has one built in

oh well eh !

ta

stu
Title: Boost cut?
Post by: TRex on February 28, 2005, 06:14:03 PM
QuoteOriginally posted by grinder
you should have said - i have a spare FCD in the garage !

stu

 .:spank