Footman

iTrader: (2)

Hey guys,

I want your opinion and experience on this one. I got these codes, took the car to the dealer, and they decided to change my spark plugs with new ones. I drove out the lot, tried to go up in the RPM's... same issue occurs and CEL comes back. I'm going back to the dealer on Monday to drop the car off for more serious diagnostics.

Going back, in the past 3.5 months of ownership of this new car, I've had been back 3 times for CELs. I've gotten P0103 (MAF Intake too much air), P0300/P0302 Misfire on Rotary chamber 2, and now P0300, P2097 (Air/fuel too rich), P0172 (System too rich).

To describe what's happening... it feels like beyond 4000 rpm, if you are at light throttle... you feel the engine sputtering and hesitating. However, if you give it more gas, it goes away and spins up. It's most pronounced in 1st gear, and gets less pronounced as you go up to 6th gear. Mind you, it's still present in 6th gear, since if I cruise at 135 km/h or so... in 6th gear it's just around 4200rpm or so.. you can feel the car hesitating and stuttering, but it keeps driving. It's like as if there is some throttle chopping going on.

I have looked at all the threads concerning those DTC codes listed; but I want to know some real world experiences that you guys may have come across in your ownership with the 8.


I have several speculations
a) does this have anything to do with the brutally cold temperatures we have this winter in Toronto?
b) does it have to do with me having the MS CAI, so at speeds the air going into the intake isn't stable?
c) all the salt/snow/sand combo we've been getting in Toronto entering the CAI and making it dirty real fast? (I do have the sock installed).
d) These problems never existed in the first 1.5 months of ownership, though temperatures were much warmer then. Is the RX-8 not revvable in very cold temperaures?

The car has been running on nothing but V-power 91, and I do check/top off engine oil with Castrol GTX 5W20. I am very worried about the longevity of the car now. I've been treating it really good ever since mechanically and cosmetically... and seems like it's just not reciprocating the love

spd frk

I have an issue of a similar nature. Ever since I added the RP supercat to my system I have been getting P301 (i think) misfire in Rotary Chamber #1. I sometimes get a little hesitation with a grumbling noise from the motor as I accelerate hard in a high gear 5/6th from about 4000rpm.

I believe dirt on the filter has a lot to do with it (i have athe RB w/air duct) especially in the winter time. I think otherwise the problem is 2 fold.

1) the CAI can really pack a lot of air into the intake at high speed and I think this causes the air to back up from the motor and fool with the MAF readings by flowing across it.

2) the size of the exhaust and the change in cat may be screwing up the 02 readings or putting them to a spec the car can't adjust to.

You obviously don't have the same parts but may be having a similar problem. Depending on your mileage I would also recomment putting in new coils and plug wires. I put in RB plug wires and noticed a smoothness improvment.

Smokin_LaLa

hope this helps.....

https://www.rx8club.com/showthread.p...ht=compression

HEVNSNT

How's the idle? Smooth or rough?
How does it start? Right away or cranks too long?

Footman

iTrader: (2)

It starts right away. Idle's smooth.

HEVNSNT

Then I wouldn't worry about the motor being bad yet. When the CEL comes on does it stay on?

Footman

iTrader: (2)

It flashes then stays on. Then I floored the car to redline in 2nd gear, and then shift, and redline in 3rd gear, and it flashed again.. and then stayed on.

So it went from flashing --> on ---> after 1 minute later, I decided to floor it and then it went flashing ---> on.

HEVNSNT

Sometimes one problem may result in conditions that will trigger other codes. Try to narrow down what code is the source of the real problem. Reset the code by disconnecting the battery for a minute. Run the car again and check the code as soon as the CEL comes on.

My guess (and only a guess) is it's the MAF sensor.

Footman

iTrader: (2)

you can hear the car throttle sound like someone is chopping it.. like there's some air turbelent sound from under the hood...

HEVNSNT

This only happens under load? What happens if you rev it up in neutral (no load)? Does it rev up smoothly? Reset the code and rev it up in neutral, does the CEL come on when you rev up in neutral?

Footman

iTrader: (2)

the CEL is on now... I can't reset it without going to the dealer. I'll wait till Monday to see what happens. They changed my spark plugs today. They will take my car in on Monday and do a full diagnostics in detail.

I will rev it tonight when I get off work in neutral to see what happens at higher RPM's in terms of the "throttle chopping" phenomenon.

DarkBrew

Man that sucks!
Have them check the plug wires and MAF sensor

Gecko69

I have a hiflo cat and mazdaspeed cai...no cels at all.......its a car by car basisis with this vehicle.....my car has been good to me, others haven't had an experiance as good as mine. I have heard of people getting cels from the cai but it does sound like an issue becasue of the cai, maybe a maf sensor issue.....have you tried to clean your maf sensor??? it could be restricting the amount of air its letting in making your car run a little rich??? just guessing but its worth a try.

Footman

iTrader: (2)

Ok guys,

I drove it around for 45 minutes so it's all warmed up. I revved it in neutral, and its sputters past 5000rpm... so it can't possibly be too much cold air rushing into the CAI... something else is wrong.

Hvnsnt, any ideas? dirty MAF (on a 3.5 month car)??? faulty O2 sensor?

Gecko69

spark plugs??? coils??? maf??? I would check those.......and yeah your car is 3.5 months old....but you never know. worth a checking a few things before the dealer makes you sign your life away.

ROCKSTAR RX8

I had the same problem on my car... it came from the CAI when it's cold and you have some water on the filter itself....

Since I don't drive the car as much so after I parked the car for a few days and the CEL went away by itself....

It sucks in the winter where the air filter is located right behind the grill and water/salt/dirt get on it very easily... I don't know, maybe put the stock intake back on for the winter??

Footman

iTrader: (2)

I got new plugs already yesterday. So perhaps new coils and new maf?

From the previous codes I got, anything to do with the O2 sensors and catalyst?

Gecko69

hmmmm......I have the same part and dont have those problems........and I have even had ice frozen over my filter at one point when we had a large snow fall one day........i dont think a little bit of water or a damp filter would cause your engine to sputter above 5000 rpm???Rockstar probably knows a little more than I do about mazdas as he was a manager but I still dont see how this would cause this problem....you are still getting as much or more flow with the cai with a wet filter as you would with a stock air filter........you wouldn't be bringing water into the engine...the air would be " humidified " if anything......which shouldn't cause this......again I am just guessing and by no means an I a mazda mechanic.........I am just saying that if this was the actual problem then we would all be experiancing it...I definately would have as my filter was almost completely covered by ice and gets damp/wet all the time as well. You should have enough air flo, why else would your engine sputter??? poor combustion, lack of spark.....maybe the wet filter is the problem, but I just dont have it on my car with the same/ worse condition air filter.

Gecko69

it could be coincidental but, a lot of other people are having this issue and replacing their coils fixed the problem.........again, could be a coincident but might not be??

HEVNSNT

So it does sputter after 5k rpms in neutral? Start with changing the cai back to stock. I don't think it would be the O2 sensor. The O2 is not a factor under load conditions which is when you got the CEL.

zerobio

Hope you get this worked out Footman.

Footman

iTrader: (2)

I can't perform the intake swap myself. I have an appointment with the dealer on Monday to get it all sorted out. I can suggest to him what I think (but I don't want to **** off the technician with my input, cause that's like "stepping on his toes" kinda thing for his job).

If the car is stopped and I rev and it sputters. How would the CAI be the factor? cause no wind is blowing into the car, the air input should be consistent at rest (no turbulence)?

P2097 and P0172 both talk about running too rich, and possible O2 sensor failure... oh man, I feel bad that no one else in Toronto is getting that. I hope it's just cause the weather is too cold or something... It didn't do this in November when I first got the car and the temps were above 5 degrees.

Now the windchill everyday is like - 15 or more!

Gecko69

personally I dont think its your intake......seriously....pull out the maf from the intake and see if there is any debris on it, something is limiting the amount of air in your engine to make you run too rich.......checking the maf is a 30 second thing...unscrew it and pull it out and look at it. if its not that then you will be looking at something possibly more expensive to fix. Its not the weather.....I live in kingston and its always a little colder or the same temperature here that it is in toronto. then take a look at your throttle body.....take the intital pipe off the intake and see if you can move the valve inside.....maybe its stuck??? there are a lot of things that it could be....but I doubt its your intake.

Footman

iTrader: (2)

I don't have any brake cleaner. Can I use compressed air (the stuff to clean computers) and blow inside?

Footman

iTrader: (2)

How can a MAF get so dirty in 3.5 months?!?!?!