Another Boost issue thread...

[Locki]

Hi Everyone. First of all I would just like to say a big thanks to everyone here at MRC, I\'ve been here a while now (I WILL renew my membership soon :o) and there are so many helpful, friendly, people here. One day I hope to have as much knowledge of the Rex as most of you, and then I will be able to return the favour a give something back to the site.

Anyway, a while ago i posted a few issues that were bugging me and I got alot of helpful replies :cheers I also had the car booked in at WGT for a health check for this weekend. However, due to a few personal issues i had to cancel the appointment, so I decided to buy a boost gauge for a little "self diagnosis". I read the posts on how to fit it, and on what boost i should be getting etc (thanks again), but to cut this long story short, sometimes my car boosts ok, but then sometimes it doesn\'t (sometimes boosts at 12p.s.i sometimes at 8p.s.i) I\'ve looked at hundreds of posts here, and there\'s obviously quite a few things it could be.

I really want to learn myself, but i have absolutely NO mechanical experience what so ever. I read that there are hoses to check, solenoids, and the "rats nest" etc, but i have NO idea where any of these things are :S. Could someone please be so kind, and either show me some pics of where everything is i need to be looking at (i.e rats nest, which hoses, solenoids etc) or point me in the right direction of a site that has the info?

Sorry for the extremely long post, and for the really noobie questions, but i am really keen on learning everything there is to know. Thanks in advance to anyone that kindly responds.:Thumbs-up

[rustyrex]

hi bud iwas the same just 3 months ago wen i had no boost at all never worked on o rx befor all ican say is read read read till your eyes bleed the get the spanners out and get right down on er
the rats nest nest is ever so daunting but you just gota go for it remember what goes where and think logical all the time your workin on it
however it might not be "the nest" might just have a loose or leaky pipe on intercooler or somthin?youl get there

[JohnP]

read the last post i did, first page in this thread:
 
http://www.mazdarotaryclub.com/forums/showthread.php?t=49240
 
dont be put off by the scary diagram.. the first thing to check is really easy to get to, and was giving me random boost, particularly random above 5k rpm

[JohnP]

infact, where in northants are u?  i\'m at wellingborough. could show u where to start.

[Locki]

infact, where in northants are u?  i\'m at wellingborough. could show u where to start.

Lol, i\'m about 10 minutes away from you mate:Thumbsup! I live in Raunds. I would really appreciate some advice sometime whenever you\'re free? Cheers!

[neil_jdmr]

read the last post i did, first page in this thread:
 
http://www.mazdarotaryclub.com/forums/showthread.php?t=49240
 
dont be put off by the scary diagram.. the first thing to check is really easy to get to, and was giving me random boost, particularly random above 5k rpm

 
The check valve you changed is the same one im having an awful lot of bother trying to get off. one side hose slips off no problem but the side under the uim is stuck solid and i dont want to force it too much as it disappeers under the uim.
 
I have changed two others and both were screwed so im thinking the rest will probably want changing. So any tips on getting the hose of the check valve or do i grow a set and just pull it harder (ooer madam).

[Archbish]

Easy checks first...  If it only boosts when it\'s cooler, and if it\'s hotter and ceases to do so, then check the intercooler or intake hoses.  These can start to collapse as they get older - one of mine certainly did, and that resulted in periodic boost loss.  

Otherwise, the solenoids on the front of the upper intake manifold would be a favourite of mine to have a look at.

[Locki]

Easy checks first...  

Only problem is, I don\'t know the easy checks mate. I don\'t know where the solenoids.etc are, what they look like, or what to look for if they are knackered. I understand what to look for with the hoses (splits.etc) but again, to me there\'s a LOT of hoses under my bonnet, and i don\'t know which ones i\'m loking at :S Lol sorry guys, i guess it\'s like trying to teach a baby how to walk...but feel free to patronise me at any time and speak to me as though i was a foreigner trying to understand english :Giggle

with any luck i\'ll be able to meet up with john sometime and start with some of the basics from there.

Thanks again everyone, before you know it i\'ll be the one handing out advice! :rolleyes:

[sickboy2345]

http://www.autosportracetech.com/RX-7/BoostTest.htm

http://www.autosportracetech.com/RX-7/PrimaryTurboLeakDiagram.htm

http://www.autosportracetech.com/RX-7/TurboTroubleshooting.htm

http://www.rx7.org/Robinette/hoses.htm

that should help mate, im gonn abe reoplacing my vaccum lines next week...my boost was playing up lately too..

[Locki]

http://www.autosportracetech.com/RX-7/BoostTest.htm

http://www.autosportracetech.com/RX-7/PrimaryTurboLeakDiagram.htm

http://www.autosportracetech.com/RX-7/TurboTroubleshooting.htm

http://www.rx7.org/Robinette/hoses.htm

that should help mate, im gonn abe reoplacing my vaccum lines next week...my boost was playing up lately too..

Mate! that is spot on! suppose it helps if you know where to look and what to search for. I\'ll be spending a few hours looking through all this lot. Thanks again mate, just the kind of thing i was looking for :Thumbs-up

[Locki]

One last thing then... If any of the hoses, rubber connectors, or solenoids etc are faulty, where wold be the best place to purchase the replacements? Local mazda garage? or....?

[sickboy2345]

glad i could help

if you want them parts cheap just go //www.fduk.org(and go to wanted section - its free just get registered) , ebay, or here:

//www.jimmys-rx7.co.uk

email to jimmys-rx7 :

ajc@jimmys-rx7.co.uk

just tell them what you need and they might be able to help you.

if you want to go expensive got o you local dealer.

hope that helps

Lucas

[Locki]

Excellent! Thanks again mate! Just been reading up on those sites, everything is starting to look alot clearer now! Guess i\'m gonna be busy this weekend...

[JohnP]

alrite guys, as for meeting up, I wont be able to make this week as me and the mrs are off to france for our first wedding anniversary, but i\'m sure we could sort something for next week.
 
You shouldnt have to go under the uim to get to the check valve i changed. If you look at the actual picture of the valve i photographed, it isnt the one thats in focus, its the slightly blur\'d one behind it which is stated in the post!
 
If the valve is intact, and the hoses secure, I would check AFTER the check valve to see if the hose has popped off at the turbo end (sumwhere under your air intake box/induction kit pipework leading to back of engine bay)
 
Any q\'s, txt me on 07984 190133 and maybe we can sort out meetin up to try and get too the root of it! make sure u txt tho guys cos i work all kinds of hours

[JohnP]

and does your sympton sound like the second one explained in this table:
 
http://www.autosportracetech.com/RX-7/symptoms.htm
 

Primary Only	4,500 RPM	Primary and Secondary	Check
Solid 7 psi	Solid 7 psi	Solid 7 psi	Missing pills for Wastgate and/or Turbo Pre-Control Actuators. Wastegate and Turbo Pre-Control Solenoids are elctrcially unplugged.
Spikes above 14 psi		Spikes above 14 psi	Hose from Primary Turbo Compressor to Wastegate and/or Turbo Pre-Control Actuators has popped off.
Solid 12 psi		5 psi or less	One of the vacuum hoses connected to the pressure tank, pressure tank chack valve, or hose between turbo and check valve. They will come off again unless the hose is replaced or zip-tie it at both ends.
Hear boost leak		Hear boost leak	Y-Pipe coupler