Guess what? my cheap rotary has a misfire
03-26-2022, 04:56 PM
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Guess what? my cheap rotary has a misfire
'i bought a rotary!'
'good luck'
My RX8 is misfiring terribly, so much so it smells an idles like a two stroke. The car wouldn't start originally, but that turned out to be the main fuse.
The car was owned by my friend, he drove it into his driveway and it stopped. main fuse as before mentioned was the cause of no start, a few people before me tried to get it to strat and replaced the starter and so on. the friend in question actually just bought the car and then drove it home, decided he was too funky and sold it on, so i cant speak for how well it ran before exactly. (hes always been honest, and said it ran well)
I replaced the ignition coils and leads. I thought the Spark plugs were good, but couldnt check since i dont think i have the correct socket. Anybody know the size?
Im fairly certain i have the wires to the correct plugs, ive a diagram that im going to reference tomorrow. im a bit upset that the ignition coils and plugs didnt fix it, even when they have white burn marks on the back.
ive yet to clean the MAF and so on, but i struggle to believe something like fuel trims could make the car shake and misfire so bad it backfires on and off throttle. Is this engine rebuild time? it was 400 euro....
'good luck'
My RX8 is misfiring terribly, so much so it smells an idles like a two stroke. The car wouldn't start originally, but that turned out to be the main fuse.
The car was owned by my friend, he drove it into his driveway and it stopped. main fuse as before mentioned was the cause of no start, a few people before me tried to get it to strat and replaced the starter and so on. the friend in question actually just bought the car and then drove it home, decided he was too funky and sold it on, so i cant speak for how well it ran before exactly. (hes always been honest, and said it ran well)
I replaced the ignition coils and leads. I thought the Spark plugs were good, but couldnt check since i dont think i have the correct socket. Anybody know the size?
Im fairly certain i have the wires to the correct plugs, ive a diagram that im going to reference tomorrow. im a bit upset that the ignition coils and plugs didnt fix it, even when they have white burn marks on the back.
ive yet to clean the MAF and so on, but i struggle to believe something like fuel trims could make the car shake and misfire so bad it backfires on and off throttle. Is this engine rebuild time? it was 400 euro....
03-27-2022, 10:27 AM
#2
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How many miles/km are on the engine? (gives indication of engine lifespan)
How many on the car? (gives indication of other components on car)
Can it Cold start + crank time? (gives indication of charge system health)
Can it Idle until hot? (gives indication of timing/fuel/ignition/vacuum issues)
Can it idle when hot? (gives indication of low compression85%, ignition7%, vacuum5%, or fuel3% issues....my general rx8 estimated chances knowing it can idle cold fine) (compression gets lower as the engine heats up)
Can it Hot Start + crank time? (indication of low compression....again just in general for rx8s)
New plugs, Clean the maf, check the front O2 sensor, and check if your Cat is clogged. The rear O2 is really just to see if you have a cat or not.
From my extensive experience with dying renesis engines if you are misfiring and running rich all the time then you will likely be fouling plugs. Getting new plugs+leads+coils is a smart first choice, just know that these may not be the entire issue. If there is another issue causing you to run rich or lean you may potentially foul your new plugs quicker than you think and symptoms will return.
Even if you end up fixing the issue I'd suggest either getting a compression tester or finding someone in the area with one. Compression will give you a good indication on how much life the engine has left. One of the first signs people come across with low compression are longer and longer hot starts until the car can't hot start. Then the car won't idle hot, which at this point I would expect extensive wear on the engine. Rebuilding before these symptoms occur could potentially save you from excessive wear or catastrophic damage. Always check the price of reman engines before buying individual engine components.
How many on the car? (gives indication of other components on car)
Can it Cold start + crank time? (gives indication of charge system health)
Can it Idle until hot? (gives indication of timing/fuel/ignition/vacuum issues)
Can it idle when hot? (gives indication of low compression85%, ignition7%, vacuum5%, or fuel3% issues....my general rx8 estimated chances knowing it can idle cold fine) (compression gets lower as the engine heats up)
Can it Hot Start + crank time? (indication of low compression....again just in general for rx8s)
New plugs, Clean the maf, check the front O2 sensor, and check if your Cat is clogged. The rear O2 is really just to see if you have a cat or not.
From my extensive experience with dying renesis engines if you are misfiring and running rich all the time then you will likely be fouling plugs. Getting new plugs+leads+coils is a smart first choice, just know that these may not be the entire issue. If there is another issue causing you to run rich or lean you may potentially foul your new plugs quicker than you think and symptoms will return.
Even if you end up fixing the issue I'd suggest either getting a compression tester or finding someone in the area with one. Compression will give you a good indication on how much life the engine has left. One of the first signs people come across with low compression are longer and longer hot starts until the car can't hot start. Then the car won't idle hot, which at this point I would expect extensive wear on the engine. Rebuilding before these symptoms occur could potentially save you from excessive wear or catastrophic damage. Always check the price of reman engines before buying individual engine components.
03-31-2022, 03:46 AM
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Hi, sorry for the late reply, hectic week!
the car has 65,000 miles on body and engine. I’m aware that’s right around engine rebuild time, and I’m fairly certain it’s the original engine. To start the car I’ve gotta keep cranking for 5-6 seconds to start it with a little throttle. I’ve never let it warm up, I know rotaries don’t like that but it runs far to bad to let it. Sometimes it dies out.
I’ll clean the MAF, try afford spark plugs, I’m almost sure there’s a cat but it could be a dummy pipe ( not having a cat is illegal here ). I’ve looked into it further and realise almost anything can get these to misfire bad. I’m a Subaru guy, but bloody hell…
any ,ore tips or what to do it’s great appreciated. Thank MincVinyl
the car has 65,000 miles on body and engine. I’m aware that’s right around engine rebuild time, and I’m fairly certain it’s the original engine. To start the car I’ve gotta keep cranking for 5-6 seconds to start it with a little throttle. I’ve never let it warm up, I know rotaries don’t like that but it runs far to bad to let it. Sometimes it dies out.
I’ll clean the MAF, try afford spark plugs, I’m almost sure there’s a cat but it could be a dummy pipe ( not having a cat is illegal here ). I’ve looked into it further and realise almost anything can get these to misfire bad. I’m a Subaru guy, but bloody hell…
any ,ore tips or what to do it’s great appreciated. Thank MincVinyl
04-11-2022, 07:03 AM
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Hey, i've been having the same issue but it has been resolved now.
Try checking the e-shaft sensor in the front of the engine nere the belts. Give it a quick clean and make sure the plug is making a good connection. Then turn the key to run/start (without starting the engine) and spam the brake pedal fully on and off till the oil pressure gauge moves up and down (you have to do it for at least 10sec). Then turn the car off and go for a start. For my understanding this calibrates the sensor. There is a few posts on here about it.
In saying that i have a sneaky suspicion that may not work because when i was having a misfire issue it still idealed and started fine, not the best cold tho. Worth a shot, as its free to try.
Also if it has a really strong petrol smell and on a cold starts with no/little wind it make your eyes water when you get out of the car. IT DEFINITELY DOES NOT HAS A CAT. Don't ask me how i know that
Try checking the e-shaft sensor in the front of the engine nere the belts. Give it a quick clean and make sure the plug is making a good connection. Then turn the key to run/start (without starting the engine) and spam the brake pedal fully on and off till the oil pressure gauge moves up and down (you have to do it for at least 10sec). Then turn the car off and go for a start. For my understanding this calibrates the sensor. There is a few posts on here about it.
In saying that i have a sneaky suspicion that may not work because when i was having a misfire issue it still idealed and started fine, not the best cold tho. Worth a shot, as its free to try.
Also if it has a really strong petrol smell and on a cold starts with no/little wind it make your eyes water when you get out of the car. IT DEFINITELY DOES NOT HAS A CAT. Don't ask me how i know that
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