Loss of power & rattle, help!
#50
Joined: Nov 2007
Posts: 7,521
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From: Caput Mundi
Check your flash before replacing parts. Older flashes had lower metering rates. The omp's shaft also wears under some circumstances, causing it not to immediatly "engage" the stepper motor.
Apparently you're bringing the car to marketing specialists as they keep suggesting that you buy parts...
Why use protek when there are oils of which the formulation is clear and have known properties?
Using less premix is not a wise idea. 200\240grammes is fine for a normal "fill-up".
Apparently you're bringing the car to marketing specialists as they keep suggesting that you buy parts...
Why use protek when there are oils of which the formulation is clear and have known properties?
Using less premix is not a wise idea. 200\240grammes is fine for a normal "fill-up".
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From: Great Britain
It's been back to the Mazda dealers for the latest PCM upgrades a while ago, the only one it hadn't had was the 'hard to start' reflash. They haven't investigated any of the running problems for me and the local Mazda dealer doesn't even have a rotary compression tester.
Do you have a link for checking the OMP for wear?
I haven't taken the car to any marketing specialists. The only suggestion Haywards came up with was that the rear silencer was rotten and needed replacing, I didn't even buy my new exhaust from them. The rest of the work has been carried out by me, mostly guesswork really as there wasn't a lot of info to push ahead with.
I'm not using Protek at the moment, just some Castrol 2-stroke oil. Protek looks a little on the expensive side to me, what is your recommendation?
Do you have a link for checking the OMP for wear?
I haven't taken the car to any marketing specialists. The only suggestion Haywards came up with was that the rear silencer was rotten and needed replacing, I didn't even buy my new exhaust from them. The rest of the work has been carried out by me, mostly guesswork really as there wasn't a lot of info to push ahead with.
I'm not using Protek at the moment, just some Castrol 2-stroke oil. Protek looks a little on the expensive side to me, what is your recommendation?
Driving Lady
Joined: Jul 2011
Posts: 6
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From: Singapore
Hi Boys,
Any follow up for this? Mine's stuck at the garage now, we're waiting to see if a fully de-cat cat put in would make a difference now. Have changed my o2 sensors and it's not the problem.
My problem here: https://www.rx8club.com/series-i-trouble-shooting-95/power-loss-about-7k-sputtering-no-cels-no-other-vital-signs-219208/ ---> basically a loss of power at 7K rpm with no CELs, sputterings and no other signs, everything else seems dandy after checking and there's still no answer.
Hopefully the de-cat would do the trick. Suspect it may be like one of the dudes here whose cat was stuck way back rather than at the surface.
Thanks
Any follow up for this? Mine's stuck at the garage now, we're waiting to see if a fully de-cat cat put in would make a difference now. Have changed my o2 sensors and it's not the problem.
My problem here: https://www.rx8club.com/series-i-trouble-shooting-95/power-loss-about-7k-sputtering-no-cels-no-other-vital-signs-219208/ ---> basically a loss of power at 7K rpm with no CELs, sputterings and no other signs, everything else seems dandy after checking and there's still no answer.
Hopefully the de-cat would do the trick. Suspect it may be like one of the dudes here whose cat was stuck way back rather than at the surface.
Thanks
Driving Lady
Joined: Jul 2011
Posts: 6
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From: Singapore
Hi Manic, none of my valves/ports are stuck =) update on my thread.
Hi Bro,
We've did a switch on coils yesterday just to be sure and it didn't work. Still the same.
Our Cat has been cleared to a straight pipe. But this time, the engine seems confused. After a reset, we've found that the sputtering occurs randomly throughout the 4k rpm range and beyond. We can work the car but not redline it constantly, and after it warms up considerably, the sputtering and random slight lurches (like we've released clutch in first gear at low speed) seems more eminent.
We had a fuel pump problem previously that was changed about 4 months thereabouts ago. We had a loose fuel tank seal previously as well that had been changed. We suspect that the fuel pump may be the culprit again as the sputtering seems to attribute to some fault with the fuel injection to the engine chambers (or some sort as my fiance explained).
We were wondering if it could be a possiblity with the fact that after the reset, could the default fuel trims (I understand that there should be a long term FT map and a short term one) be unable to deal with the fact that we've been revving it to test if the power loss is still present? We're of the opinion that the car needs to learn the driving pattern and adjust the FT to the necessary before it's able to communicate rationally with the rest of the vehicle. Right now, could it be a case that the fuel is running too thin?
I'm not sure what the heck I'm talking about right now, but I only know that the warm up of the vehicle after the initial drive off and rev seems to have balked the engine and confused it. The sputter occurs randomly through and it can be driven but not long distance. We've noted there are no rocks in the engine.
The compression test we did in the last few days was balanced according to our resident Jap boss at the garage and their more or less convinced it isn't a case of poor compression. I clarify that we have power now but the sputter now seems to be hindering the allowance of acceleration, which in the end makes us tap the accelerator more and more gingerly. I have no idea why!
I hope you guys get what I'm trying to say. =)
We'll be running another set of tests today as well as a dyno and removing the fuel pump as well. Will update!
Thanks!
We've did a switch on coils yesterday just to be sure and it didn't work. Still the same.
Our Cat has been cleared to a straight pipe. But this time, the engine seems confused. After a reset, we've found that the sputtering occurs randomly throughout the 4k rpm range and beyond. We can work the car but not redline it constantly, and after it warms up considerably, the sputtering and random slight lurches (like we've released clutch in first gear at low speed) seems more eminent.
We had a fuel pump problem previously that was changed about 4 months thereabouts ago. We had a loose fuel tank seal previously as well that had been changed. We suspect that the fuel pump may be the culprit again as the sputtering seems to attribute to some fault with the fuel injection to the engine chambers (or some sort as my fiance explained).
We were wondering if it could be a possiblity with the fact that after the reset, could the default fuel trims (I understand that there should be a long term FT map and a short term one) be unable to deal with the fact that we've been revving it to test if the power loss is still present? We're of the opinion that the car needs to learn the driving pattern and adjust the FT to the necessary before it's able to communicate rationally with the rest of the vehicle. Right now, could it be a case that the fuel is running too thin?
I'm not sure what the heck I'm talking about right now, but I only know that the warm up of the vehicle after the initial drive off and rev seems to have balked the engine and confused it. The sputter occurs randomly through and it can be driven but not long distance. We've noted there are no rocks in the engine.
The compression test we did in the last few days was balanced according to our resident Jap boss at the garage and their more or less convinced it isn't a case of poor compression. I clarify that we have power now but the sputter now seems to be hindering the allowance of acceleration, which in the end makes us tap the accelerator more and more gingerly. I have no idea why!
I hope you guys get what I'm trying to say. =)
We'll be running another set of tests today as well as a dyno and removing the fuel pump as well. Will update!
Thanks!
Last edited by xladyzstarx; Jul 5, 2011 at 09:11 PM.
Thread Starter
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From: Great Britain
Footman, the premixing has stopped the rattle completely on mine.
Not sure if I have an oil injection issue, it may not be putting enough in the intake through the standard oil injectors - which incidentally have passed the blow through and leak down tests.
Not sure if I have an oil injection issue, it may not be putting enough in the intake through the standard oil injectors - which incidentally have passed the blow through and leak down tests.
#50
Joined: Nov 2007
Posts: 7,521
Likes: 11
From: Caput Mundi
With all the due respect for the british shops, some of them tend to mess these tests up. Ask Shifty about his experience 
Premix IS a band-aid after the problems appear, you should start it earlier to prevent them (or delay...)
Some bogging issues can be solved with an injector cleaning too. Our system is return-less too, under some circumstance other similar things may happen, due to some of the fuel system components.
I'm trying to **** you off, just trying to help since you guys up there act a bit strange at times and tend to believe the "gurus" too much
Premix IS a band-aid after the problems appear, you should start it earlier to prevent them (or delay...)
Some bogging issues can be solved with an injector cleaning too. Our system is return-less too, under some circumstance other similar things may happen, due to some of the fuel system components.
I'm trying to **** you off, just trying to help since you guys up there act a bit strange at times and tend to believe the "gurus" too much
Thread Starter
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Joined: Jul 2010
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From: Great Britain
No problem, I'm still relatively new to the world of Wankelling!
My compression test results were shown previously in the thread, plus just about every brand of fuel system treatment has been used in the past 18 months. Lambda readings suggest fuelling is spot on, coolant temps good, coil packs, wires and plugs brand new, CAT good too.
The specialist I used is a well respected firm, Hayward North in Doncaster. Mazda often take RX-8s to them for repair. Local Mazda dealers don't even have a rotary compression tester, believe it or not...
I fully believe that premixing is covering up a problem, but I'm wondering if the issue with mine is isnufficient oil injection causing poor sealing under load.
My compression test results were shown previously in the thread, plus just about every brand of fuel system treatment has been used in the past 18 months. Lambda readings suggest fuelling is spot on, coolant temps good, coil packs, wires and plugs brand new, CAT good too.
The specialist I used is a well respected firm, Hayward North in Doncaster. Mazda often take RX-8s to them for repair. Local Mazda dealers don't even have a rotary compression tester, believe it or not...
I fully believe that premixing is covering up a problem, but I'm wondering if the issue with mine is isnufficient oil injection causing poor sealing under load.
Dodging those Corollas
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Joined: Oct 2006
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From: Stouffville, Ontario, Canada
I've done BG44K AND a can of seafoam in the gas tank, so I've ruled out all fuel injector issues.
I refuse to put seafoam into oil reservoir because we know an oil change doesn't change all the oil in the entire system (some in coolers still).
I'm thinking of doing a seafoam into the induction side of things directly into the combustion chambers next.
I refuse to put seafoam into oil reservoir because we know an oil change doesn't change all the oil in the entire system (some in coolers still).
I'm thinking of doing a seafoam into the induction side of things directly into the combustion chambers next.
Thread Starter
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From: Great Britain
Do the seafoam method shown on here, with the hot engine/starting disabled/1 hour soak (think that's what you're referring to).
If you haven't tried, chuck 150ml of 2-stroke oil in the gas tank before you fill up, that amount won't do any harm and it might solve things to give you some direction for fault finding.
If you haven't tried, chuck 150ml of 2-stroke oil in the gas tank before you fill up, that amount won't do any harm and it might solve things to give you some direction for fault finding.
Dodging those Corollas
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From: Stouffville, Ontario, Canada
I've done BG44K AND a can of seafoam in the gas tank, so I've ruled out all fuel injector issues.
I refuse to put seafoam into oil reservoir because we know an oil change doesn't change all the oil in the entire system (some in coolers still).
I'm thinking of doing a seafoam into the induction side of things directly into the combustion chambers next.
I refuse to put seafoam into oil reservoir because we know an oil change doesn't change all the oil in the entire system (some in coolers still).
I'm thinking of doing a seafoam into the induction side of things directly into the combustion chambers next.
Oil catcher
Joined: Dec 2010
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I had the same problem. Premixing made it disappear... but after some months it came back again even if still premixing. Now I'm waiting for an engine swap cause mine completely died some weeks ago. Good luck :-/
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I posted this ona similar thread....
I had a similar problem recently.
After new coils, leads and plugs, the problem still wasn't resolved.
Diagnostic codes all coming up clear.
I borrowed a friends scanner and did a snapshot of the ecu/pcm.
I then printed it out and read through the displayed values for each sensor and settings.
When I got to the ECT it was showing that it was requesting a voltage of 134V...Huh?
OK, I thought I'd get a sensor as they should be cheap and an easy thing to do.
I'm in the UK and a local Mazda dealership wanted 55 pound plus tax.
Did a bit of research and found it's a fairly generic sensor that comes in a multitude of cars.
Got one from an aftermarket parts supplier for 12 pounds all in.
Spent 25 minutes skinning my knuckles getting the old one out. Slipped the new one in.
Issues sorted, car runs sweet as a nut.
A little bit of Internet searching shows the ECT to be quite a common failure.
It then supplies the wrong values to the PCM/ECU and consequently the car fuels incorrectly.
Trust me, for a few dollars/pounds it's worth a try.
I had a similar problem recently.
After new coils, leads and plugs, the problem still wasn't resolved.
Diagnostic codes all coming up clear.
I borrowed a friends scanner and did a snapshot of the ecu/pcm.
I then printed it out and read through the displayed values for each sensor and settings.
When I got to the ECT it was showing that it was requesting a voltage of 134V...Huh?
OK, I thought I'd get a sensor as they should be cheap and an easy thing to do.
I'm in the UK and a local Mazda dealership wanted 55 pound plus tax.
Did a bit of research and found it's a fairly generic sensor that comes in a multitude of cars.
Got one from an aftermarket parts supplier for 12 pounds all in.
Spent 25 minutes skinning my knuckles getting the old one out. Slipped the new one in.
Issues sorted, car runs sweet as a nut.
A little bit of Internet searching shows the ECT to be quite a common failure.
It then supplies the wrong values to the PCM/ECU and consequently the car fuels incorrectly.
Trust me, for a few dollars/pounds it's worth a try.
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Sorry ECT sensor, is the engine control temperature sensor.
It sits in the back of the themostat housing with a two wire multiplug connection.
The one used in the RX8 is actually a very commonplace sensor that is used in a wide variety of cars, (so no need to pay dealer's inflated prices!)
I replaced mine with one from Intermotor, #55123.
Online catalogue at www.intermotor.co.uk shows how widely used it is and cross-references other manucaturers part numbers too.
Initially I was very sceptical that this could be the cause of the misfire and sluggish high rpm running, but after replacement it's been perfect and I've driven ca. 900 miles since replacing it.
As I said the PCM interrogates the data output from the ECT sensor as one of it's variables used to create the correct fuel/timimg trim, so if it's faulty it means the PCM fuels incorrectly.....
My car was showing no DTC codes, but I had the opportunity to delve a little deeper with the scanner/computer and read through the values stored in the PCM for each sensor..... I really thought it was too easy a fix, but I was pleasantly surprised....Hopefully the same applies to the o/p
It sits in the back of the themostat housing with a two wire multiplug connection.
The one used in the RX8 is actually a very commonplace sensor that is used in a wide variety of cars, (so no need to pay dealer's inflated prices!)
I replaced mine with one from Intermotor, #55123.
Online catalogue at www.intermotor.co.uk shows how widely used it is and cross-references other manucaturers part numbers too.
Initially I was very sceptical that this could be the cause of the misfire and sluggish high rpm running, but after replacement it's been perfect and I've driven ca. 900 miles since replacing it.
As I said the PCM interrogates the data output from the ECT sensor as one of it's variables used to create the correct fuel/timimg trim, so if it's faulty it means the PCM fuels incorrectly.....
My car was showing no DTC codes, but I had the opportunity to delve a little deeper with the scanner/computer and read through the values stored in the PCM for each sensor..... I really thought it was too easy a fix, but I was pleasantly surprised....Hopefully the same applies to the o/p
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From: new york
my car did this for the first time yesterday. It was about 90 degrees outside. I was shifting down to accelerate onto the highway and the car was struggling to go. I have an AEM intake and the noise it made was twice as loud as the normal AEM intake sound. BUT i wonder if getting a shutter valve stuck open code 6 months ago could be the culprit? I haven't seen the code pop on again yet though. This didn't do it all today and ran just fine. Im leaning towards the ssv and possible carbon buildup?
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From: Great Britain
Engine coolant temp sensor.
Dude, seriously - have you tried any of the things already suggested in the thread, namely go and get a compression check done, try a bit of premix? The premix costs pence, sorry cents to try and in some cases fixes all the problems. Your issues sound identical to mine but you won't follow the advice from people on here...?
Dude, seriously - have you tried any of the things already suggested in the thread, namely go and get a compression check done, try a bit of premix? The premix costs pence, sorry cents to try and in some cases fixes all the problems. Your issues sound identical to mine but you won't follow the advice from people on here...?
Dodging those Corollas
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Joined: Oct 2006
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From: Stouffville, Ontario, Canada
Premixing is something the factory did not intend on doing, and thus I will not do premixing even if it "supposedly" fixes the problem. I also believe that pre-mixing is simply a bandaid solution to a problem and eventually it will re-surface.
Compression check, I will do that when all my options are exhausted. I have been very busy lately, still haven't had time to do a seafoam induction cleaning yet, so that is next on my to do list. Also, I have an appointment with dealership next Saturday Aug 6 to check the CAT for warranty claim because I had the CAT removed and I looked at it myself and found a crack line going all across the honeycomb.
Dealership wants $160 for a compression test, and my car does not have the symptoms of low compression. No hard starts when hot, no idle issues.
Compression check, I will do that when all my options are exhausted. I have been very busy lately, still haven't had time to do a seafoam induction cleaning yet, so that is next on my to do list. Also, I have an appointment with dealership next Saturday Aug 6 to check the CAT for warranty claim because I had the CAT removed and I looked at it myself and found a crack line going all across the honeycomb.
Dealership wants $160 for a compression test, and my car does not have the symptoms of low compression. No hard starts when hot, no idle issues.