khoney

This is the first time I've had a problem with the car. It's a pretty hot day today (>90), and I was driving home. Car was warm, A/C on, about 30 minutes into my trip. I took off from a light (not real hard), and heard what almost sounded like a misfire or predetonation. I drove a few miles farther and was in my subdivision going up a hill, when I hear what almost sounded like a grating noise at around 4000 RPM. I turned the corner and came to a stop sign, and when I stopped, it died and won't start again. Seems like it's flooded. I'm going to let is sit for a while and cool off, and I'll try to start it again. Any idea what this might be?

Ironically, I called the dealership today to schedule an appointment for plug/filter change. I told him I'd also like them to fix my idle vibration problem, which I've been complaining about since 18K miles (I have 37K now). He asked what octane gas I've been using. I've used either 89 or 93 octane, but almost always 89. He said that will cause carbon build-up, rough idle, and stalls. The car has run well since I've had it, and I've never had it stall on me unitl today. I routinely take it to 9K rpm to avoid any carbon build-up problem. Is it possible that this problem is related to gas? Sorry if this has been addressed elsewhere, but the unsophisticated search engine didn't help.

I'm going out to check on it, but will look for advice when I get back. Thanks, all.

zoom44

i think your cat died

nzarnow

Just let them run a diagnostic on it.... I am taking my 8 in because the stupid ventilation system is broken and the heater is perm. on.

shaolin

I had a very similar experience, what happened was the float in the gas tank got mis aligned, and I actually ran out of gas, but the gauge showed me at half.

khoney

Well, I went back out to the car after letting it sit about 30 minutes. I cranked it for about 6 seconds, and it started. There was no CEL, and it acted normal on the way to the house. I'm thinking it was somehow heat-related.

Zoom - I've been worried about the cat, because this is a 09/03 K-flash build.

Does anyone think I can call BS on the 89-octane? I have never had any power loss or hesitation problems with this car, even as recently as yesterday - it just goes like a bat outta hell.

I no longer have a warm fuzzy about the dealership - I had been dealing with a great service tech ever since I bought the car, and I found out today that he's no longer there. So this new guy gives me the instant phone diagnosis for my idle vibration problem, saying it must be my problem because I've been using 89-octane gas, causing carbon buld-up, yadda yadda. How does one accumulate carbon build-up when the car hits 9K RPM alt least 5 times per tankful?

Do you think I can call BS on the gas explanation?

valpac

iTrader: (2)

Never give the dealer an out. They'll take it everytime.

rxeightr

I have been using 87 octane for the last 18,000 miles (26,000 total) with no issues, and I doubt your symptoms are a result of carbon build-up.

The Cat does not sound likely, as they seem to fail after a flood. You did not mention having a flooding issue prior to this incident, and you had no loss of power after startup.

Did you have any CEL? If not, my suspicion lies with the spark plugs, if they are original.

Keep us posted on what you find.

TxRx8

Dude, that just happened to me two weeks ago! After I got the car back on, I drove to the dealership. The ride was terrible let me tell you. Rough as hell! Turns out I just needed an oil change. Seems to be working fine now. I have a few blips here and there with the idle, but no harm done. I hope.

zoom44

the gas issue is BS. octane is an indicator of how easy it is to ignite the fuel 89 is easier to ignite than 93. so you should be geting more complete combustion with the 89. but that doesnt mean there isnt some carbon build up. it just means its not from the lower octane gas.the amoun this car runs rich combined with an intially over working mop could easily have left some build up over time.

jaguargod

So when they say it is your problem, does that mean they do not want to cover it under warranty? If that is the case, jump up their ***. If 89 octane caused damage to your engine, then in the manual, and inside the fuel door, it would say "Premium Required". It only says Recommended inside the fuel door, and I believe it says the same thing in the manual. I thought it says you can use fuel with a lower octane than 91, but that you will have diminished performance. I don't care what a mechanic or service manager says, that manual is the "bible" and as long as you follow that, you're going to be okay in my opinion.

fray

iTrader: (1)

In fact I looked at the manual in my RX-8, and it says 87 octane or higher is required, 91 or higher is recommended for better performance.

So the tech is full of BS. They can't deny a warentee claim based on 87+ octane.

LostAngel

I'm not sure on the compression of the RX-8, but I know higher compression engines need higher octane gas.

zoom44

the higher octane is recommended to help prevent knock/pre-detonation. if the computer senses a knock it will retard timing in order to prevent more. the change will also reduce performance hence the manuals wording about reducing performance. but the higher octane itself produces no performance benefit. in fact as i stated earlier since the hiher octane is more resistant to ignition, if the car is run alot at lower rpms then the carbon build up will occur sooner causing lower performance.

khoney

Thanks for the opinions. I also think the gas excuse is BS. I don't think they'd use it to avoid warranty work, bu they me use it to avoid looking for the real vibration problem, which I believe is related to something loose under the car or a a cracked engine mount.

With respect to the car dying, there was no CEL, but maybe it stored a code. I'll have them check it. BTW, the car drove just fine today, and it is in the 90's again, just like yesterday. Very weird.

khoney

Well, the exact same thing happened again yesterday. It was a very hot day, and I had been sitting in a lot of traffic. Same mettalic grinding sound and loss of power. I managed to get home, but I don't know what the hell is happening. It was fine today (although it was cooler out). I really think it has to do with high ambient temps.

Twin 8s!

Well, I had a very similar experience. Running 80 on interstate, 86 degrees and humid, four people in car, A/C running. I came off the interstate, slowed, downshifted, and tried to merge into traffic. NO POWER.

Let up on gas and merged in. Got to the next light and ran briskly through the gears. At 6000 in 3rd, I had a rattling, grinding sound. I let off. Got home and shut it down.

Charles R. Hill

iTrader: (7)

Could this be yet another set of examples of the MOP problem? With insufficient oil supply the seals will fail to seal properly and a loss of internal pressures will result, kinda like blown compression rings in a piston engine. Take a look at the Finish Line Performance website to see the MSP04 tech bulletin. I think it not only discusses noise and loss of power above 6,000 rpm's but it also mentions stalling while hot or coolant temp sensor problems. Something like that. Mazda is gonna be hurtin' if they don't get this stuff resolved.

CRH

TeamRX8

iTrader: (25)

they already are hurting, the latest polling just came out on manufacturer warranty claims and Mazda, while not the worst, is at the bottom of the list for number of claims per hundred vehicles

edit: tied for 2nd to last to be exact



Brand performance

J.D. Power's survey of 2005 car buyers found an industry average of 118 problems reported for every 100 vehicles. Here are the number of problems per 100 vehicles for each brand:

Above average

Lexus 81

Jaguar 88

BMW 95

Buick 100

Cadillac 104

Mercedes-Benz 104

Toyota 105

Audi 106

Infiniti 109

Hummer 110

Hyundai 110

Honda 112

GMC 113

Lincoln 113

Acura 116

Below average

Jeep 120

Mercury 120

Nissan 120

Chrysler 121

Chevrolet 127

Ford 127

Mitsubishi 129

Pontiac 129

Dodge 130

MINI 130

Scion 134

Saab 136

Saturn 136

Subaru 138

Kia 140

Volvo 140

Porsche 147

Volkswagen 147

Land Rover 149

Mazda 149

Suzuki 151

Source: J.D. Power and Associates.

jerryf

Happens to me on hot days also. Going to the dealer in the a.m.

khoney

I wonder if there will be an epidemic - I was at the dealership this morning at 7:20AM, and I left at about 7:45. While I was there, 3 other RX-8s were dropped off. I would have asked what they were in for, but I was busy talking to some poor soul who was driving to Florida from San Diego with his wife and 2 kids to attend his father's funeral. His alternator went out somewhere in West Texas. He had to buy three batteries to get to San Antonio, where he thought he could get an alternator. I felt so bad for him - he said if he wasn't on the road by noon, he'd miss his dad's funeral.

TeamRX8

iTrader: (25)

they could have pulled one off an inventory car

khoney

Update - the service dept. called today asking for permission to do a 40-mile test drive. The guy said that Mazda Tech Line was requesting the test be performed and that data be collected, especially O2 sensor data. I'm not sure which problem this is meant to address - the hot temp loss of power and stalling, or the request I made that they check the cat because after the N flash I smelled rotten eggs for about 3 weeks. They did say they were going to replace my engine mount to hopefully fix my vibration problem.

Also, I woke up at 3 AM to the sound of hail - perfect time to have my car sitting at the dealership instead of in my garage...

MDRX8

Mazda needs some new tech' who can identify problems without guessing!! They never check or go through the car throughly. They just well it in and out!! And you call Mazda help line and get no help. They say it is up to the dealership.

Step up Mazda!

Charles R. Hill

iTrader: (7)

A prime example of relying too much on computers to do the thinking; if there is no CEL there must not be a problem.

CRH

khoney

Well, they drove the car 77 miles since I dropped it off. They collected data on it and sent it to tech line. Last thing tech line wants them to do is remove O2 sensor and check to see if cat might be breaking up.

BTW, I asked if they saved the plugs as I had requested. He said they were probably already packed up to be sent to Mazda. He said everything with the exception of liquids is sent back to Mazda for analysis and verification of warranty claim. He said he could go pull them out of shipping, but I told him not to bother.