Sorry for the long title firstly :)
Picked up my new Rex off of Shark yesterday and love it :) though after i had brought it home i went to take it out and found that i dont have the first turbo working, have done some searching here and found others stated their first turbo worked when second had come on boost and revs were still 2k+ in that gear so tried this and sure enough the first turbo worked 100%
On the search most of the threads i have found havn\'t had a solution stated though i have read that it could be due to a one way valve in the rats nest?
Can anyone confirm this at all?
Cheers,
Alex
Could be a dodgy solenoid, bad one way valve or a leaking vac pipe.
What level of boost is the car running when you get boost ?
Shaun
ok i have had this problem for ages now and no one could diagnose it and after about 7 hours looking on forum after forum and posts i have found what it is doing it.
TEST
start the car up and look at the valve that lets the second lot of boost through on the pipe coming from your second turbo to the y pipe.
it should be closed on tick over mine isnt so all your boost is going through the relief valve but when you get past a few revs it finally closes and you can build up boost until it opens and doesnt shut again.
i bet this is your problem it is not damaging anything i have not yet fixed it but you can then find the vacuum diagram and find out which solenoid valve and pipes that connect to that change them all and should be fine.
if you need more help email me at cushingx@hotmail.com (cushingx@hotmail.com) hope i have helped i have had it for 3-4 months now not having boost all the time its annoying lol
Quote from: shaunwil;571077Could be a dodgy solenoid, bad one way valve or a leaking vac pipe.
What level of boost is the car running when you get boost ?
Shaun
around 0.1bar building up to about 0.3 by the time second turbo comes on at which point it boosts to the normal 0.9/1.0 bar on that turbo
Quote from: cush;571121ok i have had this problem for ages now and no one could diagnose it and after about 7 hours looking on forum after forum and posts i have found what it is doing it.
TEST
start the car up and look at the valve that lets the second lot of boost through on the pipe coming from your second turbo to the y pipe.
it should be closed on tick over mine isnt so all your boost is going through the relief valve but when you get past a few revs it finally closes and you can build up boost until it opens and doesnt shut again.
i bet this is your problem it is not damaging anything i have not yet fixed it but you can then find the vacuum diagram and find out which solenoid valve and pipes that connect to that change them all and should be fine.
if you need more help email me at cushingx@hotmail.com (cushingx@hotmail.com) hope i have helped i have had it for 3-4 months now not having boost all the time its annoying lol
Not looked at the RX7 engine bay Y pipe etc setup to be honest so will take a look at that when i get a chance :o
May well give you a shout once have had a chance to take a look at it all.
Cheers,
Alex
Could be a solenoid problem. Anything over stock boost levels of 0.7bar reduce the life of the solenoids forcing them to stick.
More likely a vac line has popped off, usually you would see more boost.
Shaun
What turbo are you running ?? The stock twins will only do 1bar with some fuel and cooling mods.
Shaun
As far as i know its stock twins, running Apexi induction, Kakimoto (sp?) catback exhaust and has a Apexi FC which was mapped by Carl
Had a quick look around it but couldnt spot any visual problems though i didnt take the inlet plenum off (is this a big job?)
Just had a quick look at FDowners.com and seems a easy enough job, will have a look at it tonight more than likely also look at taking it apart to check the Y pipe :)
Def sounds like a sticky solenoid.
I had a similar prob and a pressure regulator worked a treat. basically I set the regulator to 10psi and this stops any pressure over this getting to the control systems of the turbos and screwing them up, i\'m running 14psi and at that pressure the solenoids are next to usless so limiting the pressure that gets to them fixed my probs.
But only try that once your checked the one-way pills and the solenoids themselves.
Getting the phlenum off is not a big job TBH, just take your time and check EVERYTHING is unconnected before you lift it off, so many people have snapped nipples off the double solenoids (myself included), there is some info on how to remove it here bud: clicky (http://robrobinette.com/manifold.htm)
What you describe sounds very strange.
Typically you will not see ANY boost from the second turbo if the first has not first hit 7 PSI. The fact you are making any boost at all after 4k RPM is odd (at least, not an issue I had heard of).
There are plenty of known issues and fixes for the second-turbo not coming on line. You\'re issue is the opposite though?!
I recommend popping down the A34 to Carl. I\'m pretty sure he knows this car, and has done the servicing on it previously.
The 1st turbo is making boost other wise the 2nd would not work, the boost is not going through the engine tho, so it has to be a control issue.
Hello,
don\'t want to jump on your thread but i have the same problem with my 1st turbo.
No more than 0.16 kg/cm of boost on the 1st turbo through 1st 2nd and 3rd gear and no more than 0.05 kg/cm in 4th and 5th gear.
Once above 4k (most of the time sticking on 1st turbo) the second turbo the boost is 0.77kg/cm in all gears and flies along lovely :driving
What does this sticking and lack of boost on 1st turbo mean?
^^ Knackered solenoid bud, mind did exactly the same thing yours is doing, you need to replace the 2nd solenoid back (from the front of the car) with one that can hold the boost you\'re running.
Did intend to take the car with me to Newbury on thursday (my works HQ is there) and see if i could pop to Carl while i was there but ended up taking the company car as was in meetings all day anyway so couldnt get out of the office unfortunately.
Bobbit when you say you used a pressure regulator what exactly was used?
Intend to take a look at this issue after i\'ve serviced the car this morning... now where did i put that spark plug thread :wiggle
Also forgot to mention but when so revving to 3.5-4k or so and letting off get a woosh of air kind of noise, sounds kind of like an owl? assume this is the air that should\'ve been going in my engine :(
Cheers,
Alex
have a look here bud: clicky (http://www.rx7club.com/showthread.php?t=480079)
it will be that the actuator charge control is not shuttiong so all your boost is going through the relief valve i am fixing mine today
For the record, this was not happening at the time of sale, when I took Alex out in the car prior to sale and I have never had a single day of trouble with the car. I don\'t want anyone thinking I sold a broken car.
To try and be helpful:
From experience of resolving boost problems with the FD I had before this one, the best way to resolve is to understand what should be happening at each stage...
I believe the most likely culprits from what you have described are either:
[LIST=1]
- Turbo Control Valve / Turbo Control Actuator
- Charge Control Valve
If this Turbo Control Valve is open then exhaust gas is being split between both turbos all the time - explaining low pressure below 4500 revs because the pressure is reduced and the secondary turbo is not a closed system - venting it\'s boost pressure and so I suspect spinning pretty freely.
The Charge Control Valve isolates the secondary turbo until ready to supply boost so if open then all boost will be venting until after 4500rpm.
If memory serves you can get to the actuator from under the driver\'s side behind the front wheel worth checking the control arms which I know have popped off on other FD\'s. Naturally as these are attached to the turbos expect them to be warm for some time after the engine is switched off.
All this is based on looking at Vacuum diagrams and understanding how the system works. Information for review can be found here if you look about halfway or so down the page - clickety click (http://www.rx7.org/Robinette/boost_note.htm)
If others can contradict or correct me on these points then please feel free, but this is where I would focus my attention rather than taking the plenum off and risking damaging solenoids that are probably fine or you wouldn\'t have correct boost on the secondary turbo.
Hope this helps you out.
Hi guys thanks for the replies :)
The car went to see Carl and the guys at Hayward Rotary yesterday, repairs/investigation were both a bit more extensive than i would of liked but cant fault the guys dedication to getting the car to a point where it was driveable for the time being - top guys i must say.
Anyway onto the cause of my issues.
First turbo wasnt boosting due to a faulty solenoid, once this was replaced I took it out for a test drive and first turbo boosted brilliantly however had at this point lost the second turbo with the boost just trailing off.
Left the car in the guys capable hands while i returned to work at this point and once had been dropped off again afterwards the problem with second turbo had been traced down to the Apexi PFC not controlling boost properly, so a standard ecu was fitted for the time being and it runs brilliantly.
Was intending to get a new PFC straight away however due to finances think this may be delayed a bit unfortunately.
But in the Interim the car runs brilliantly, it does very very occasionaly have a millisecond of stutter going high up the revs which is a breakdown on the ignition amp so will be taking the guys advice on fitting a small power boost type wire to there to help this out :D
Huge thanks to Hayward Rotary with this and also to all of the help offered in the thread :)
Quote from: Bobbit;573064^^ Knackered solenoid bud, mind did exactly the same thing yours is doing, you need to replace the 2nd solenoid back (from the front of the car) with one that can hold the boost you\'re running.
Hey Bobbit,
(http://i70.photobucket.com/albums/i89/Dmdrifting/rx7solenoid.jpg)
Where is the boost solenoid located? Is it one of the two green ones that bolt onto the intake plenum above?
Anyone have a photo, as i can\'t confirm which is the correct one to replace from the workshop vacuum diagrams?
Hi Bud, the solenoid in question is under the UIM i\'m afraid, so you\'ll have to remove it. Took me about 2 hrs the 1st time i removed it, but be very careful when you do remove it that you have disconnected all pipes etc, otherwise you\'ll snap the double solenoids (the one in your pic) like I did.
(http://i70.photobucket.com/albums/i89/Dmdrifting/Middlevacuumdiagram.png)
Would like some advice on correct solenoid!
It states that solenoid (E) is Turbo Control Solenoid
But in the picture above ^^ it marks \'Solenoid Valve\' (Turbo Control) to the solenoid with the purple vacuum line?
Which one is the correct one to replace?
And, are all these solenoids the same unit, or will Solenoid (E) not work in solenoid (F)\'s place?
HELLLLLLLLLP me :confused: :2Confused
The solenoids are interchangeable in as much as if one breaks then a spare is exactly the same as any other solenoid. Best thing to do is what I did and test all the solenoids to check if one is not working, I did a write up on how to check here bud: clicky (http://www.mazdarotaryclub.com/forums/showthread.php?t=44377)
I did not think it would be that easy ARGHHHHHHH, do they sit in a row under the UIM? Any answers to the post above^^?
Love the video signature hahhahahaha
Thank you thank you thank you thank you thank you :god
No probs bud, the solenoids sit in a row when you get the UIM off, mine was the 2nd back frm the front, so i\'d suggest trying that one first. Good luck bud!
Quote from: Bobbit;578707The solenoids are interchangeable in as much as if one breaks then a spare is exactly the same as any other solenoid. Best thing to do is what I did and test all the solenoids to check if one is not working, I did a write up on how to check here bud: clicky (http://www.mazdarotaryclub.com/forums/showthread.php?t=44377)
http://robrobinette.com/images/hoses.gif
So the one i need to replace is the second one back: Solenoid (F) - Charge Control? As seen in the link above!
And not Solenoid (E)
I don\'t have the tools to test the solenoids at the moment, will change and confirm the outcome
I think it is E bud, think the above pic is for an automatic and they have more solenoids but i\'m not 100% sure TBH. I basically bought a whole replacement set and between the one\'s I had and replacements I\'d bought, i had a whole set that works and a few spares. All pressure tested to 15psi so if anything goes again I have a few spares to replace it with.
But if you can, get a mityvac and pressure gauge, 12V bettery (I used one from my petrol heli, was about £20) and you\'re set, in total should cost about £50-70. In comparison to taking it to a specialist to diagnose it\'s very cheap to do.
i have changed this one 3 times and mine still isnt working can someone tell me which coloured plug goes to which solenoid valve please
Right finally got round to changing the solenoid i had been sent, it was not the same as the one you have advised to change Bobbit but i thought as the UIM is off i might as well replace!
Found a cracked vacuum plug and replaced also
The solenoid i changed is the \'Solenoid Valve - Turbo Control\' situated at the top left of this picture!
(http://i70.photobucket.com/albums/i89/Dmdrifting/Solenoidvalvepicrx7.jpg)
I have put it all back together, now the second turbo will not come on at all????
It sounds like its boosting crazy (Cars is running 2 BOV\'s one for charge and one for BOV) and it always dumps to atmosphere while under load or whilst out of gear and just revving?
Any ideas?
Should i change the solenoids back over as the new one maybe faulty?
(http://www.mazdarotaryclub.com/forums/%5BIMG%5Dhttp://i70.photobucket.com/albums/i89/Dmdrifting/Solenoidvalvepicrx7.jpg%5B/IMG%5D)
Quote from: GhostWKD;573121Also forgot to mention but when so revving to 3.5-4k or so and letting off get a woosh of air kind of noise, sounds kind of like an owl? assume this is the air that should\'ve been going in my engine :(
Cheers,
Alex
Have exactly the same noise (Owl) now that I have replaced the \'solenoid valve - turbo control\' when I rev engine at stand still or while on load driving???
Car will not run onto second turbo, it will release boost through the BOV while car is out of gear?! Shouldn\'t normally do this if im correct?!
Helllp
Would a restricting pill/washer in the vacuum line help in keeping the pressure below 10psi?
Just a thought
Anyone on here?
could this be the the charge relief solinoid?solinoid H on the diagram,looks easy to check if the uim is off as its on top of the rats nest towards the front,if that solinoid is dodgey surley the boost will be dumped all the time? just a thought.
Did you test all the solenoids bud, I can be done in situ but it\'s a bit of a bugger.
Hi all,
Not sure if it helps at all, but as said my problem was down to a solenoid :) second from the back on the right hand side iirc (96+ rats box lol)
I managed to clean the solenoid you mentioned to check, and the one i replaced i swapped back, took the two that sit on the front of the uim off too and clean them up and initially it worked better:
Switched between turbos ok and more boost on 1st turbo, but all night it has had trouble going above 0.4 - 0.5 bar, once or twice in a few hours it went to 0.6 but only on 1st turbo??
Before i was seeing 0.7 - 0.79 on second turbo???
Haven\'t had the time to check them all :(
Random question what noise should the pills make when blown through??
1.Whoosh/rush
2. Squeak
Hard to explain myself but i\'m sure someone will get me?? lol