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Hello, I bought my 05 RX8 about 3 months ago and it always ran really strong, never had issues until recently only sometimes (quite rare) when I go to start it, it would be hard to start and if it did start it would be as if it ran on 1 rotor but then would be better after it rev'd a bit and then brought back down.
Now here's the thing. Last time I drove it home it had NO issues, ran great and I parked it in the parking spot. Now its a no start issue, towed it to the shop and they claim its a bad motor with coolant in the motor. Any thoughts on this? It never blew white smoke out the tailpipe.
They claimed they spent 3 hours and multiple techs looking into this. They informed me they pulled the spark plugs and found coolant in the motor.
Here is my troubleshooting while it was at the house. I assumed it was a fuel issue since trying to start had no positive results but when turning the key from off to acc 5 times in a row the motor wanted to start and attempted to but it would immediately die.
Yeah, just pull the plugs and crank the engine with the gas pedal all the way to the floor.
Any liquid(coolant, fuel, etc.) should get swept out.
If there is indeed coolant, you don't want to leave the engine sitting for long... The rotor is made of cast iron and can rust easily with coolant/water in the engine.
Yeah, just pull the plugs and crank the engine with the gas pedal all the way to the floor.
Any liquid(coolant, fuel, etc.) should get swept out.
If there is indeed coolant, you don't want to leave the engine sitting for long... The rotor is made of cast iron and can rust easily with coolant/water in the engine.
Cool! I did not know this thanks! I will do this. The shop quoted me 6600 for a used motor with 1 year warranty and I think 8800 for a new motor with a 2 year warranty. I definitely plan on getting the car back and doing my own troubleshooting to verify any of what they said is true. Thanks for your help guys and things I can do to troubleshoot
A Mazda reman motor (90% new parts) is US$3000 + freight. Add in an extra US$1000 for tools, parts, incidentals, etc. Add in another US$1200+ for removal/reinstallation.
Sure, sure, and how long would those "running RX-8" last?
Running doesn't mean "running well".
Running doesn't mean "makes as much power as it's supposed to."
Running doesn't mean "will last more than a year or two".
Running doesn't mean "isn't a total basket case in every other area".
Maybe you're in a position where taking on that kind of risk sounds like a good plan. I'm not. I just want my car to work and the best way to guarantee that is to start with a known quantity and add more known quantities.
I got the Rx8 back at my place and I pulled the plugs. It appears that the trailing plugs are flooding with oil and isn't able to spark properly. I did not see any white on the plugs or signs of coolant.
I cleaned the plugs and cranked over the car while the plugs were out to help deflood the motor of whatever is in there. I then put the plugs back in the car and then the car started right up but then died again. I pulled out the trailing plugs again and they were filled with oil, is this normal? Is there something that is controlling the oil to be injected into the motor? What is the next thing I should be looking for? Just pulled the plugs on one of the rotors and this is what they look like. The plugs on the other rotor are the same way. Cleaned the plugs. This is after the car started and then me pulling it out again.
I assume you will be getting your money back from the garage who can't tell oil from coolant?
Take apart your intake. Is it soaked in oil? Is the oil level above full on the dipstick?
If oil is overfilled it can end up being pushed up into the intake via the fill neck. Also, if there is an excess of blowby pressure the same thing happens.
Clean up the intake and especially the MAF sensor if oily and try again. It might smoke for a while.
I assume you will be getting your money back from the garage who can't tell oil from coolant?
Take apart your intake. Is it soaked in oil? Is the oil level above full on the dipstick?
If oil is overfilled it can end up being pushed up into the intake via the fill neck. Also, if there is an excess of blowby pressure the same thing happens.
Clean up the intake and especially the MAF sensor if oily and try again. It might smoke for a while.
Yeah they actually did not charge me but I bought them all drinks the next day "thinking they were nice about everything" but turns out this situation is getting more far from what they told me. Figures. Honestly I'm really thankful for all of you to help me walk through this.
The oil is actually at the low line on the dip stick. I will check the intake and maf for oil thanks for the direction! I will reply back with details on my findings.
Well pulled apart the intake Hose going up to the throttle body and I see some oil on the bottom of the intake housing but the throttle body looks clean and opening the butterfly up amd feeling around it appears to be dry. Is there still possibly an oil issue in my intake and I need to dig further into my intake or is there something else I should be looking at?
Is there anything specific that controls the amount of oil getting injected into the motor?
The throttle body is not important. The MAF and air filter are. Clean all of that out thoroughly with the right cleaners (not brake kleen or anything like that).
Possible you took a gulp of oil and need to clear it out. What exactly happened on the drive before you found it to not start?
This is not an oil injection problem. Even at full tilt the oil injection system doesn't flow enough to flood your engine with oil.
The throttle body is not important. The MAF and air filter are. Clean all of that out thoroughly with the right cleaners (not brake kleen or anything like that).
Possible you took a gulp of oil and need to clear it out. What exactly happened on the drive before you found it to not start?
This is not an oil injection problem. Even at full tilt the oil injection system doesn't flow enough to flood your engine with oil.
The intake only had a bit of oil on the bottom. The maf is nice and clean and the air filter is only a little bit dirty.
The car ran smooth and strong on the way back from work. Nothing wrong with the car on that trip and no check engine lights. That's what has me baffold. The next morning I go to start it and it just wouldn't start.
The interesting thing is that I pulled the plugs again and the same thing happened to where the trailing plug is flooded. So I cleaned the plug and tested the plug by grounding it to the body and cranked it over while my Dad checked it for spark. It was indeed sparking but looked like a weak spark. I pulled out the other trailing plug and it was flooded but his time before cleaning it ilwe did the same test and it would not spark! I then cleaned it and it was sparking again but I know if I put it back in the car it's jist gonna get flooded again to where it is not able to spark.
The way the leading spark plug is clean as if there was no oiland the trailing gets flooded immediately and then the car isn't starting. I wonder why this is happening only to the trailing plug on both rotors. Any ideas?
The trailing plugs sit in a little cavity and are swept by the rotor tip before the leading plugs, which are more exposed. So oil gets packed into the trailing plug first, then there is nothing left for the leading. Seems about what you would expect. In fact the little cavity itself may be oily and that's what fouls your trailing plugs, as opposed to any additional oil being packed into it.
So there are 3 scenarios here:
-the oil came in via the intake, which can happen on a tired engine at high rpm or if oil is overfilled This is why I asked about oil in the intake and how it behaved on the last drive. This is treatable with a catch can.
- the oil is coming in via failed oil control rings. The only treatment is a new engine.
- the shop who was diagnosing your car added oil via the spark plug holes in an effort to get it to start and now everything is covered in oil
I'm really hoping we can confirm or eliminate the first or 3rd, before concluding it's the second.
What's the current state? It cranks and cranks forever but doesn't fire? Does it sound like it is trying to fire? Have you tried the deflooding procedure? Do all 4 spark plugs spark? Do you hear the fuel pump run/prime? Is there fuel going into the engine?
The injection system is computer controlled based on load and rpm, but it also has physical limitations. The amounts injected even at peak is fractions of a milliliter per revolution. So I don't think it's capable of delivering the amount of oil you're seeing.
The trailing plugs sit in a little cavity and are swept by the rotor tip before the leading plugs, which are more exposed. So oil gets packed into the trailing plug first, then there is nothing left for the leading. Seems about what you would expect. In fact the little cavity itself may be oily and that's what fouls your trailing plugs, as opposed to any additional oil being packed into it.
So there are 3 scenarios here:
-the oil came in via the intake, which can happen on a tired engine at high rpm or if oil is overfilled This is why I asked about oil in the intake and how it behaved on the last drive. This is treatable with a catch can.
- the oil is coming in via failed oil control rings. The only treatment is a new engine.
- the shop who was diagnosing your car added oil via the spark plug holes in an effort to get it to start and now everything is covered in oil
I'm really hoping we can confirm or eliminate the first or 3rd, before concluding it's the second.
What's the current state? It cranks and cranks forever but doesn't fire? Does it sound like it is trying to fire? Have you tried the deflooding procedure? Do all 4 spark plugs spark?
The injection system is computer controlled based on load and rpm, but it also has physical limitations. The amounts injected even at peak is fractions of a millimeter per revolution. So I don't think it's capable of delivering the amount of oil you're seeing.
Loki thank you so much for all of your input and direction, I really appreciate it.
I will try to get a catch can setup into place and let you know how it goes afterwards.
I did replace the oil filter just to see if the last one was clogged and causing extra pressure to go into the intake but that was not the case.
The leading spark plug looks to have a better design honestly especially for not being able to flood as easily due to the cuts in the plug. Is there by any chance I can run a different design plug in the trailing position? If so do you have any links to ones I can get at amazon or autozone? I know this will be solving a symptom and not the issue but none the less I would like to look at all options.
Er wait a catch can isn't going to help you start, it'll only help you not have this happen again. The plugs are designed the way they are for many reasons, I wouldn't mess with them. Keep in mind that neither is designed to handle the volume of oil you're seeing.
I would really question if this oil is actually from the shop's attempts to start the car. Is the oil on the plugs as clean as on your dipstick? If that's the case we should probably focus on ignition and fuel delivery.
Technically you should still be able to start the car without the trailing plugs firing. Please describe exactly what it does when you try to start it.
Er wait a catch can isn't going to help you start, it'll only help you not have this happen again. The plugs are designed the way they are for many reasons, I wouldn't mess with them. Keep in mind that neither is designed to handle the volume of oil you're seeing.
I would really question if this oil is actually from the shop's attempts to start the car. Is the oil on the plugs as clean as on your dipstick? If that's the case we should probably focus on ignition and fuel delivery.
Technically you should still be able to start the car without the trailing plugs firing. Please describe exactly what it does when you try to start it.
Understood, thanks for the clarification on the catch can.
When I first blew out the plugs with compressed air I also took my air compressor and blew in the spark plug holes to get all the junk out of it as possible. I also cranked it over a few times with the spark plugs out of the motor and my gas pedal to the floor to help clear out additional fluids. After I did that the car started right up and rev'd to 2-2.5k Rpms but then immediately started sputtoring and then died. Then I was not able to turn it over any more.
I really like your statement about the shop. They could of added oil to help compression but I feel like I did a good enough job flushing it out.
After cleaning the plugs by just wiping them up with a rag and putting it straight back in the car it would start too about 1k rpm then die immediately. I assume this was cause I did not flush it out as well as the first time.
Invest $15 in a HEI ignition tester to verify the coils are good.
You can get a spark checking the old way like you're doing, but the tester will show you if it's a good spark.
Idk what's wrong, but I'd suspect that or possibly fuel delivery.
If you plan on keeping it, you could try testing the fuel pressure if possible.
I'm on my 3rd fuel pump in 6 years, so maybe yours is weak.
Before you start changing parts, try a proper troubleshooting method.
If you haven't seen this thread yet it may help.
Invest $15 in a HEI ignition tester to verify the coils are good.
You can get a spark checking the old way like you're doing, but the tester will show you if it's a good spark.
Idk what's wrong, but I'd suspect that or possibly fuel delivery.
If you plan on keeping it, you could try testing the fuel pressure if possible.
I'm on my 3rd fuel pump in 6 years, so maybe yours is weak.
Before you start changing parts, try a proper troubleshooting method.
If you haven't seen this thread yet it may help.
Scrolling through this I saw the ESS mentioned.
Did you clean that?
Also be aware anytime you mess with the ESS, MAF sensor, or unhook the battery, you need to do the 20 brake pedal stomp.
(Resetting the NVRAM)
Ah so it does start. That's different. Definitely test for spark and make sure the spark plugs are wired to the correct coils. With so many hands in there, someone could have messed it up.
The above is good advice ^^
Beyond that, check for loose/cracked/open hoses or ports in the intake. There should not be any.
The only spark plugs I know for this car are from either NGK or Denso. Denso leading spark plugs lack the grooves, but I have zero trouble starting anyway. The trailing plugs have the same design.
Originally Posted by BigCajun
If you plan on keeping it, you could try testing the fuel pressure if possible.
I'm on my 3rd fuel pump in 6 years, so maybe yours is weak.
Seeing you are keeping it long term, maybe it's time to grab an S2 unit and mod it according to that DIY thread.
Also, the 20 brake stomps technically only resets ESS data. It's quick and easy so doesn't hurt to try. If you want to reset fuel trims and other such data, disconnect the battery and wait a few minutes(10 should be good). IIRC the earlier models also need to relearn idle after a battery disconnection.
If you decide to change the fuel pump, be aware there is a recall for the fuel pump pipe, so it would be a good idea to change the pump first.
I think they put a new fuel pump ring on it, but I'm not sure.
I chewed mine up pretty good the first time before I got the handy dandy BHR fuel ring tool.
You can check to see if that and all other recalls were addressed here:
05-14-2019, 02:35 PM
Engine Coolant in engine?
