I\'ve almost had it with my FD now.
I had a problem with my FD a while back as detailed in this thread (http://www.mazdarotaryclub.com/forums/showthread.php?threadid=10142&perpage=15&pagenumber=1).
And the problem didn\'t really go away. It is, however, slightly different now.
This is the problem:
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The car runs absolutely fine when cold.
As soon as it warms up (water temperature reaches "quarter to" position), the strange behaviour starts.
I thought it was "limp home mode", but I don\'t think it is anymore, as the engine management light doesn\'t come on, and no fault codes are stored.
The "strange behaviour" is that if you apply more than just a little throttle, the power cuts completely out and it backfires.
You can ride the clutch (to get the revs up without applying heavy throttle) and get the car to accelerate up to 40/50mph+, but as soon as you put your foot harder on the accelerator, the power cuts out and it backfires.
If you pull over, turn the ignition off, and then start the car again, the car will drive fine once more - for about 200 metres, when it will go into the strange behaviour again.
If you stop and let the car cool down to 0 again, it will drive fine for a while, until the engine heats up again to normal operating temperature and the problem starts again.
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So there you go - that\'s the problem. My Dad is a mechanic but hasn\'t worked on FD\'s before, so we\'re struggling to determine whats causing it. I would take it to a specialist, but I don\'t really have the money, and I don\'t want to spend lots of money getting a specialist to fix it, when my Dad could do the labour if we knew what the problem was.
If anyone has heard of this before and knows what it could be, please let me know!
Thanks in advance
Luciano
I would have a look at the engine coolant sensors, there should be two, one for the ECU and one for the gauge. My 323 drove terribly when the ECU coolant sensor plug came loose because it would try and run in cold start mode when hot.
is the MAP sensor connected?
Regards
Carl
Map sensor is connected
Are all of the earths well grounded and clean on the contact points?Do you have a stock ECU?
Regards
Carl
I think the ECU is stock (I haven\'t changed it, and it looks stock to me)
I will check the earths - any in particular I should look out for? If an earth wasn\'t grounded well, wouldn\'t it mean that the problem would occur even if the car was cold?
Thanks,
Luciano
MikeLMR, would you please expand on this? I didn\'t know there were two. Any chance of a diagram to point out the locations please?
Thanks
(I may have a similar problem)
I think it could be your coolant sensors aswell, they are on the back of the theromstat housing, one has a green plug and one underneath is black, I think this is the one, but check both.
Does the power cut when the turbo starts coming on, if it does it could be the charge control solenoid.
Jason
on other Mazda\'s the green one is the ECU temp sensor
the black one is either for the gauge or may be the sensor for the fan.
What you are describing is almost identical to mine, except mine is more intermittent. When the fault is there, it stays there until you do anything to clear it. Then it works for several weeks or more before it fails again.
I haven\'t got to the cause of mine yet, but this is what I have discovered. There is a actuator known as the charge control valve. It\'s function seems to be to hold a valve closed on the outlet of the second turbo when the second turbo is not in use. When mine runs properly, I can measure about 600mm hg continous vacuum at this actuator, which seems to hold the valve closed properly.
When the fault occurs, the vacuum drops to around 400mm hg at idle, and this drops off as you open the throttle. As it drops to about 200mm hg, the car cuts out. I\'m guessing that 200mm hg is not enough to hold the valve closed, and so the output of the first turbo is free to flow into the outlet of the second turbo, which has the wastagate open and the charge relief valve open venting back to the air filter. I don\'t know why it causes the apparent cut out, and there is no ECU light, but Im sure that reverse flow down the second turbo is not a good thing!
You might want to measure the vacuum to the charge control valve, and if it is low or not there, trace back toward the solonoids to try to find where it has gone.
I have no idea why the car runs fine when its cold either. I\'m guessing that it might be associated with the activation of the double throuttle valve, but haven\'t worked out why!
Rgds
Keith
That definately sounds like my exact problem!! It used to be more random with my car too, but now I\'m making regular identical journeys, I can identify more of a pattern.
Someone must know why the Vacuum drops like this...?
I\'m going to replace the engine coolant temp sensors, and also the turbo actuators, and see if that solves the problem.
Also, is the turbo actuator the same as the turbo solenoid and the same as the charge relief valve? If not, what is the difference, and which do you recommend I replace?
Thanks!
:)
Just out of interest, how do you know if ECU codes are stored? And how do you read them?
Is nobody local with Apexi and Commander.
The Commander provides diagnostic readings for all sensors and its very easy to swap stock ecu for apexi (5 mins max.)
I will oblige if your in the northwest area !!
Thanks for the offer. I\'m in the North East, but have no way of getting the car to you unfortunately!
How far north and how far east.
I\'m running in at the moment, so may be tempted to cross the mountains!! to put some miles on engine.
Give me a call on 0780...... wait a minute.. I\'ll PM you.
I\'d better not publish mobile no. on forum, you know its full of \'fruit loops\' !!
hey guys, can you keep me up to date whats happening here..... having a very similiar problem - i pm\'d you my number.
heres the full story.....
To begin with my primary turbo was working ace, nice transition to second turbo too but at this point I would lose a few psi of boost
Boost pattern was 10.5…..7…..8
Couldn’t find anything obvious so decided to attempt the “vac hose adventureâ€. All went well with it â€" took me a couple 0of afternoons but I got there. Didn’t take the solenoid rack out but of the 4 hoses you need it out for none of them were hard â€" I think they must have been changed at the rebuild about 18 months ago. Every other hose was changed though.
I also replaced the following as there was more damage down there than I knew about
1. Acv Assembly (I cracked it when I was screwing it in!)
2. Air bypass solenoid (the front nipple was snapped off and not connected)
3. Charge control solenoid (same as above)
4. Aluminium Pcv valve as it was busted
5. 2 of the check valves too
Got the car back together but it wouldn’t boost above 8 psi regardless so went looking for the cause ….. I did remember that the restrictor pills weren’t as snug in the new hoses as the old ones so I used the smaller diameter of hose and squeezed them in. …. Put it back together and now on primary it’s hitting a slightly dangerous 13/14 psi….. Can’t really check if the second turbo is coming on as I’m very reluctant to boost it that hard with so much boost.
Anyways went under for another look on Saturday there and noticed the gasket on the acv was leaking so I replaced that too. Also when I was doing the vac hose replacement I noticed a vac hose that vented to atmosphere â€" as I was replacing the hoses on a one for one basis I left it to atmosphere….. Now a week later in my search for problems I realised that this hose was the second hose in the “impossible to do without removing the solenoids†list and was supposed to be connected to the block….. I then proved that you can JUST replace this one without removing the solenoids and hooked it back up. So put it all back together again and took the car out for a test…… Now it’s doing the same 13/14 psi on the primary. Did keep the foot down longer (still haven’t opened the throttle fully as I don’t want to bust the engine) and kept it boosting around 10 psi - about ¾ of the throttle and when the revs got a little higher it seemed to “buck†and lose power - hard to explain â€" it just seemed to falter for a bit (bit like fuel cut though not as sudden and no warning on the dash either) so I quickly let the throttle out and continued normally. Tried this again and same thing. I think it might be at the point the second turbo is coming online? Sorry can’t get rpm’s as I had to keep an eye on the cars in front and I don’t want to take it anywhere at the moment if I can help it.
so does seem a little like your problem! My theories are the charge control actuator or te turbo control actuator. It really does sound like the Charge control actuator ..... sounds as though it\'s opening a little but not all the way. I\'ll know more when i get the car back tomorrow -- it was in for the last week getting a boot install done! Anyhow ive me a phone tomorrow if you like and we can compare notes on it.....
I don\'t think its the same problem to be honest - mine is almost definitely linked to engine temperature.
My replacement engine coolant temp sensor has arrived (Thanks Dragon) and I\'ll fit it at some point over Christmas (probably boxing day).
I\'ll let you know how I get on.
Incidentally, if it still doesn\'t work, I\'m going to change the charge control actuator, and if *that* doesn\'t work, I\'m going to send the car to a specialist.
Just pointing out that I normally drive the car like a hearse until the temp guage actually reads halfway..... so i have no idea what it\'s like before that.....could be the same.
definately not the same problem... you know when my car isn\'t running right because if you apply more than 10% throttle it cuts out and starts backfiring... so doesn\'t matter how gently you drive - you\'d notice!
As an aside... maybe our problems are caused by Mazdaspeed MS01 alloys, I notice we both have them ;)
damn.... probably the only thig i never checked so far!!!:eek:
any idea where to get centre caps? mines have vanished..... you been in scotland recently?;)
This may seem daft but a lot of the probs sound like a split gasket sucking in air at the manifold or a primery/secondary injector not seated/worn and sucking in air past the injector as it fits into the rail.:wave if it\'s the later then you will see a type of black burn mark at the point the air is being sucked in. The reasons for stating above are that the former happened to me and it was poping and banging like a gooden with power failure just when you felt it was all well. This problem got worse over time. The later was also happening without me knowing it at the same time until Geff fitted my FC /Commander and it was hunting when the aircon was switched on. He knew what is was immediately and pulled everything out down to the fuel rails and bingo. I must say i was very impressed when he put it all back together and it sorted the problem.
QuoteOriginally posted by Luciano
definately not the same problem... you know when my car isn\'t running right because if you apply more than 10% throttle it cuts out and starts backfiring... so doesn\'t matter how gently you drive - you\'d notice!
Your engine is going into \'limp\' mode,without a doubt.It is probably the metering oil pump.Follow the wiring underneath the waterpump to the oil pump and check for damage.The wire rubs on the belts if not secure properly.If that is OK,get another pump and plug it in to the engine loom,put the pump somewhere out of the way.Test car,and if that cures it,change the oil pump.A pig of a job!
mines has now decided to imitate yours!!!!
any throttle that takes the boost over 2/3 psi the ecu cuts the fuel!
grrrr
Can you tell me where the water pump and oil pump are btw?
**update**
Changed the engine coolant temp sensor today (quite difficult to get to, but not too tricky).
PROBLEM STILL THERE
Going to see a mazda dealer tomorrow... :( not sure what else to do :confused:
QuoteOriginally posted by Luciano
**update**
Going to see a mazda dealer tomorrow... :( not sure what else to do :confused:
Read my post above!
Tim,
I saw your post - thanks a lot for responding :)
I checked the wiring to the oil metering pump, and it was safely secured and well away from the belts. I was thinking of replacing the oil pump - but as I don\'t know for sure if it\'s the cause, I could spend lots of money replacing the pump only to find out it was something else.
I\'m hoping that if I take it to a Mazda dealer they\'ll diagnose the problem (perhaps using their electronic diagnosis equipment?) and then I can repair whatever is wrong.
Is there anyway that I can test the oil pump, without replacing it?
I normally use //www.iluvmyrx7.com to download sections of the RX7 workshop manual, but the site has now been removed. I believe Section D contains information about the metering oil pump..
Without the manual I\'m not sure if I can diagnose the oil pump as being faulty, unless I replace it..
Any advice greatly appreciate - thanks again for replying
:)
Hi Luciano,
I am sure that Tim would post you one and it may not cost too much.Most of Tims parts are very reasonably priced so you maybe suprised!
Give him a call in the week on 01725 516462
Hi Tim,nice to have you on here helping out a little,we need more of those who work on rotaries to give advice.
Regards
Carl
I\'d love to find out what\'s causing this as I\'m getting the exact same problem, with varying degrees of severity. If I\'m stopping and starting all the time now and again it\'ll try to stall with more than 10% throttle, though cycling the ignition usually fixes this. More often it feels like I\'ve lost 50% power though it\'ll accelerate at 100% throttle. Building revs up when it\'s like that sometimes produces a very strange sucking (sounds bronchial!) sound between gearchanges. This has only happened since I\'ve had it serviced and is getting more common...
I\'ve been fiddling around and I\'ve found out that when the engine warms up and the problem starts, the vacuum at the double throttle control actuator disappears. Because there is no vacuum, the double throttle control actuator doesn\'t function and this is the problem. But where does the vacuum go? Hopefully Mazda will tell me this tomorrow... (my thinking is faulty Double throttle solenoid? - but then why would this only happen when the car is warm?)
I\'m going to a mazda dealer tomorrow morning, will keep you informed.
vacuum hose split somewhere?
but if it was a split hose, why would it only lose vacuum pressure when the engine warmed up to normal operating temperature? Surely it would leak at any temperature?
I think the key questions I have unanswered are: what switches on (or off) when the engine warms up to normal operating temperature. And then, why does this cut vacuum pressure?
Hopefully Mazda can answer this tomorrow morning with their diagnostics...
The heat can warm the pipes and hoses up, so a hose or pipe that is fine when they are cold might hold boost, whilst a warm flexible hose may be able to open up and reveal a split and leak boost. It\'s something to ponder about anyway!
Possibly, and that\'s been suggested as a possibility to me before. But why does cycling the ignition often fix the 10% throttle cutout problem?
QuoteOriginally posted by Luciano
but if it was a split hose, why would it only lose vacuum pressure when the engine warmed up to normal operating temperature? Surely it would leak at any temperature?
I think the key questions I have unanswered are: what switches on (or off) when the engine warms up to normal operating temperature. And then, why does this cut vacuum pressure?
Hopefully Mazda can answer this tomorrow morning with their diagnostics...
When on \'limp\' mode,the ignition and injection amount is fixed,that is why you have less vacuum,because the engine is not\'happy\'.Whatever it is ,Mazda will be able to read the fault code.
Mazda\'s diagnostics reported error number 27 (ECU fault) and advised I needed to replace ECU.
Carl (Hayward) and Tim (RXM) told me this was unlikely, but I sourced an ECU locally and tried it. - Did not fix problem.
I will now be changing the metering oil pump as Tim suggests. we\'ll get there in the end! :)
Just wanted to say thanks again to the people trying to help... I\'ve only had the car about 6 months and this problem has stopped me driving it for almost 4 of them! So I much appreciate any help.
On a slightly bleaker note, I got this private message today:
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FROM: padams2002
SUBJECT: read asap
MESSAGE: **** off find it out yaself i know wot it is had da same problem
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What\'s disturbing (apart from his inability to spell) is the fact he actually thinks not telling me his opinion bothers me.
I haven\'t bothered to reply to the message, what a fool...
QuoteOriginally posted by Luciano
Just wanted to say thanks again to the people trying to help... I\'ve only had the car about 6 months and this problem has stopped me driving it for almost 4 of them! So I much appreciate any help.
On a slightly bleaker note, I got this private message today:
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FROM: padams2002
SUBJECT: read asap
MESSAGE: **** off find it out yaself i know wot it is had da same problem
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What\'s disturbing (apart from his inability to spell) is the fact he actually thinks not telling me his opinion bothers me.
I haven\'t bothered to reply to the message, what a fool...
That is pretty nasty and unnecessary,if he did not want to help why be so nasty about it?I am not sure who he is?Can you enlighten us Luciano?
Anyway,glad you have at least eliminated the ECU.
Regards
Carl
Hi Carl,
Thanks for the chat yesterday - I\'m going to call Tim today to order the metering oil pump :)
No idea who \'padams\' is, he must\'ve just seen this thread and then decided to message me.
My dad says that in 12 years of being a Mazda technician they never replaced a Mazda ECU that actually needed replacing (a few people asked to have them changed but did not turn out to be the fault)
I\'m not saying none of hem go wrong but it is a rare occurance. He also suggested that most wiring faults are due to corrosion in plugs and connectors, the ECU uses such small currents that any corrosion can cause big problems.
Again somthing else to think about ?
Hi folks, sorry to say I think I totalled my Rex last nite. :(
Still before I did I solved the probems that were happening.......
Number of little things were causing mines...
1. The large 6mm vac hose to the pcv valve just off the uim was split.
2. An engine earth strap was off.
3. one of the vac hoses to the solenoids ( i think the pressure regulator solenoid) was split too.
4. The vac hose that comes off the solenoid in the rack - the turbo control one - had a hose coming out that had a kink in it - it was kinked against the coil assembly.
5. lastly - I took the car for a test - it was running nice - idling nicebut it was producing way too much primary boost (around 15 psi) so in a moment of inspiration I disconnected the pre control solenoid and hey presto! the car was running beautifully perfect boost pattern 10.5/8/10.5 .... amazing!
Dunno if this is any help to you but it cured my car.
:wave
Now I just need to see if I can get the car back or if they write the poor thing off!
Hi Luciano,
Been away and only just seen this thread and l am seriously not impressed with Mr Adams mail to you :reallymad
First let me apologise on behalf of MRC that you had this happen, and secondly l can tell you won\'t have that again through this Club as l have just banned him on the grounds of, this is a club that helps each others members with no tolerance for this type of behaviour also the guy has had more than enough time to apologise if he was just having a bad day letting of steam to a stranger :(
BTW, he did not have your problem as he had a split inlet gasket
( checked the guys posts)
I dont recall who padams is but the name is familiar - was it def some thing he\'d sent? theres been some wierd stuff on these forums this last year with people mssing about, eh?
Just cant see why he would send that a) cause its some thing a pr#ck would do and I vaguely recall having spoken to this guy at some point and usually remember pr#cks :) and b) its obviuosly so traceable??
If he\'s guilty then yep, of course ban him. Any one know the guy?
Hi Rich, Happy New Year to you and all in the Club.
Turns out Geff mended his car so maybe you met there.
Hi Clive, Happy New Year to yourself and Lisa too - sure its gonna be a good one :)
Hmm, I thought the name was familiar. Not sure if I\'ve met him or not - doesnt sound too pleasant a guy if it was truely malicious :reallymad - did you hear back from him about being banned?
R.
No worries clive. I\'ve forwarded you (and 20b_boy) a copy of the PM just to end any discussion about whether I was lying or not. I have to say I\'m not bothered about the message, but equally if he\'s banned I don\'t think it\'s a huge loss to the club.
Sorry to hear about your car Dale, hope you get something sorted out - let us know what the insurance says.
I will fit the metering oil pump at the weekend, and check the various hoses that were mentioned below. I\'ll then put a post up saying what the cause of the problem was (assuming I find it!) Might be helpful if someone has similar symptoms.
Gotcha, ta. I wasnt doubting what u were saying though at all! Just seems a bit dim of the guy, may be he\'s just slow-witted!
Just finished replacing the metering oil pump last night, and... THE CAR WORKS! At last.
I won\'t get to drive the car until next weekend (am away this week) but hopefully the problem will not return after further adn longer testing.
So a big thanks to all who helped!
I think its worth pointing out that Tim (RX Motors) and Carl (Hayward) from very early on said that the metering oil pump was probably the fault... so well done & thanks to them guys.. their knowledge & helpfulness really is second to none.
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So if anyone has the following symptoms:
-Car runs fine when cold
-At 80c has loss of power/vacuum (limp home mode)
-At 80c reads fault code 26 or 27
Then check first of all:
-Wiring to metering oil pump (if routed wrong, it rubs on belts)
-Metering Oil Pump (easy to test, hard to replace)
Other possibilities for similar problems:
-ECU (unlikely but easy to test/replace)
-Map Sensor (Hose disconnects easily so check connection)
-Other hoses (check connections and for splits)
-Engine earths (check for good connection)
-Engine Coolant Temp Sensor (Green ECU one)
And if it is the metering oil pump, good luck to you! Its not that expensive to buy (thanks Tim @ RX Motors) but fitting it is a pig of a job... It requires: All piping/airbox out, air con unit out, alternator out, water pump out etc etc etc - and even then its hard to get to! All in all I\'d allow the best part of a day, although the experienced guys would do it far quicker I would think.
cool glad you got it fixed, Ive been following this thread with interest with its happy conclusion
Great stuff! I\'ll pop my car into my rotary specialist armed with a printout of your post! Thanks!
think my car has similar probs, havent tested the omp :(
Try and get hold of a known good OMP, plug that in place of yours without taking yours out! it the fault clears you know your OMP is duff! if you cant change it and you suspect the OMP add premix as a precaution,to protect yout rotors etc. untill you get it sorted, do a search on OMP i\'m sure Kbareham replaced his, and he is a helpfull chap.and knows what he is doing. you could find his posts on this. Good luck.
Bob
If the OMP is duff then the car will hardly run and it will not rev ezcept on really light throttle as it will go into limp mode.
Tharek, your car did not have that fault when it came to me.
In either case,iof the car will only just drive,but not rev out then yes,it could be on default.(And in Limp mode)
Regards
Carl