2005 auto rx-8 engine pinging or knocking
#1
2005 auto rx-8 engine pinging or knocking
Hi,
I'm having issues with the engine knocking(pinging, detonating) the car is a 2005 auto transmission completely stock with no modification whatsoever and it shows no trouble codes on the scan tool. Already replaced coils, plugs, cleaned fuel lines and injectors, de-carbed engine using water and wd-40 premix(compression is at first rotor at 77,78,79 psi and at the second rotor is 83,85,88 psi) checked fuel pressure at 48psi. any help with somebody having same issue with an auto RX-8 will be greatly appreciated.
thank you in advance.
I'm having issues with the engine knocking(pinging, detonating) the car is a 2005 auto transmission completely stock with no modification whatsoever and it shows no trouble codes on the scan tool. Already replaced coils, plugs, cleaned fuel lines and injectors, de-carbed engine using water and wd-40 premix(compression is at first rotor at 77,78,79 psi and at the second rotor is 83,85,88 psi) checked fuel pressure at 48psi. any help with somebody having same issue with an auto RX-8 will be greatly appreciated.
thank you in advance.
#2
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Can you explain why you think it's pinging/detonating?
It's almost always not audible on our engines. Even a deadly detonation isn't really heard. I'm guessing you hear something you think is pinging, but is actually something else.
It's almost always not audible on our engines. Even a deadly detonation isn't really heard. I'm guessing you hear something you think is pinging, but is actually something else.
#4
thanks!
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What fuel are you using? Reg or Prem?
I did this and it helps but when the engine is HOT only Prem Gas will help....
https://www.rx8club.com/rx-8-discuss...iac%2A-121249/
I did this and it helps but when the engine is HOT only Prem Gas will help....
https://www.rx8club.com/rx-8-discuss...iac%2A-121249/
Last edited by Old Rotor; 04-25-2013 at 05:12 PM.
#6
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So to me, it just sounds like you are chasing the wrong problem and only think you are hearing knock.
Example on what knock sounds like when it doesn't immediately destroy the engine: https://www.rx8club.com/series-i-tec...cluded-243347/
I'll bow out though, and see where this goes, if you are so sure.
#7
What fuel are you using? Reg or Prem?
I did this and it helps but when the engine is HOT only Prem Gas will help....
https://www.rx8club.com/rx-8-discuss...iac%2A-121249/
I did this and it helps but when the engine is HOT only Prem Gas will help....
https://www.rx8club.com/rx-8-discuss...iac%2A-121249/
Last edited by rxtii; 04-25-2013 at 11:50 PM.
#8
I may be wrong, but I'm pretty sure that by the time the pinging is audible on a rotary the seals are already long shattered, and you would have heard the engine chewing up the seals, followed by severe lack of power and a general inability to start the engine.
So to me, it just sounds like you are chasing the wrong problem and only think you are hearing knock.
I'll bow out though, and see where this goes, if you are so sure.
So to me, it just sounds like you are chasing the wrong problem and only think you are hearing knock.
I'll bow out though, and see where this goes, if you are so sure.
#9
What fuel are you using? Reg or Prem?
I did this and it helps but when the engine is HOT only Prem Gas will help....
https://www.rx8club.com/rx-8-discuss...iac%2A-121249/
I did this and it helps but when the engine is HOT only Prem Gas will help....
https://www.rx8club.com/rx-8-discuss...iac%2A-121249/
#10
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When ambient air temps increase, as in your case, the engine is more susceptible to detonation. Also a restricted catalytic convertor will cause a build up of extra heat in the engine due to exhaust gas restriction.
Have you ever changed the ignition coils? Have you checked the Cat visually? Is the engine temperature gauge moving? If it moves the engine coolant temp is above 230+ degrees. This will also cause an increase in the chance of having detonation.
What brand of fuel do you use? Not all brands are good.
Detonation is caused by excessive heat in the combustion chamber. Causing the fuel to ignite under compression from being too hot. One must look for the cause of the excessive heat build up in the combustion chamber. Cat clogged, bad fuel octane rating, to lean a mixture A/F. Overheating coolant/engine. Does it run better when the car is cool?
Have you ever changed the ignition coils? Have you checked the Cat visually? Is the engine temperature gauge moving? If it moves the engine coolant temp is above 230+ degrees. This will also cause an increase in the chance of having detonation.
What brand of fuel do you use? Not all brands are good.
Detonation is caused by excessive heat in the combustion chamber. Causing the fuel to ignite under compression from being too hot. One must look for the cause of the excessive heat build up in the combustion chamber. Cat clogged, bad fuel octane rating, to lean a mixture A/F. Overheating coolant/engine. Does it run better when the car is cool?
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If I used 87 octane in either of my last two engines they would pings, and it is VERY audible. If my 8 wasn't in the shop awaiting its third engine I'd throw some 87 in and record the sound for you. LOL Oh, before you ask, Mazda's fix for my engines issue is don't use 87 octane.
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If I used 87 octane in either of my last two engines they would pings, and it is VERY audible. If my 8 wasn't in the shop awaiting its third engine I'd throw some 87 in and record the sound for you. LOL Oh, before you ask, Mazda's fix for my engines issue is don't use 87 octane.
There have been enough noises over the years attributed to knocking/pinging that actually aren't (like intake valve rattle, rotor tips hitting the housing, loose bolts, belts, alternator bearings, etc...) plus engines that shatter seals on a detonation that was otherwise completely silent ahead of time...
...I just struggle to believe you could hear non-deadly knock on these engines, and what people this is knock is usually something else that is being ignored because they are incorrectly labeling it as knock and troubleshooting it as such.
#13
When ambient air temps increase, as in your case, the engine is more susceptible to detonation. Also a restricted catalytic convertor will cause a build up of extra heat in the engine due to exhaust gas restriction.
Have you ever changed the ignition coils? Have you checked the Cat visually? Is the engine temperature gauge moving? If it moves the engine coolant temp is above 230+ degrees. This will also cause an increase in the chance of having detonation.
What brand of fuel do you use? Not all brands are good.
Detonation is caused by excessive heat in the combustion chamber. Causing the fuel to ignite under compression from being too hot. One must look for the cause of the excessive heat build up in the combustion chamber. Cat clogged, bad fuel octane rating, to lean a mixture A/F. Overheating coolant/engine. Does it run better when the car is cool?
Have you ever changed the ignition coils? Have you checked the Cat visually? Is the engine temperature gauge moving? If it moves the engine coolant temp is above 230+ degrees. This will also cause an increase in the chance of having detonation.
What brand of fuel do you use? Not all brands are good.
Detonation is caused by excessive heat in the combustion chamber. Causing the fuel to ignite under compression from being too hot. One must look for the cause of the excessive heat build up in the combustion chamber. Cat clogged, bad fuel octane rating, to lean a mixture A/F. Overheating coolant/engine. Does it run better when the car is cool?
thanks!
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Considering premium is required, I have to agree with Mazda on this. 3rd engine you say? And still using 87?
There have been enough noises over the years attributed to knocking/pinging that actually aren't (like intake valve rattle, rotor tips hitting the housing, loose bolts, belts, alternator bearings, etc...) plus engines that shatter seals on a detonation that was otherwise completely silent ahead of time...
...I just struggle to believe you could hear non-deadly knock on these engines, and what people this is knock is usually something else that is being ignored because they are incorrectly labeling it as knock and troubleshooting it as such.
There have been enough noises over the years attributed to knocking/pinging that actually aren't (like intake valve rattle, rotor tips hitting the housing, loose bolts, belts, alternator bearings, etc...) plus engines that shatter seals on a detonation that was otherwise completely silent ahead of time...
...I just struggle to believe you could hear non-deadly knock on these engines, and what people this is knock is usually something else that is being ignored because they are incorrectly labeling it as knock and troubleshooting it as such.
#17
absolutely! the pinging noise is almost gone maybe the lower intake temperature is helping remember the ambient temperature is 98 degrees but as I said before it could be that the bypass is putting a mask on a problem that is still there because the power loss is still felt at high rpms..
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