Engine problems with '04 RX8
 

'04 RX8, 4 speed auto. Last Sunday we were driving and the engine started losing power. The transmission was shifting into 4th at 35 mph and would not downshift. I put the trans in "manual" and the car would not accelerate past 4000 rpm at which point a loud rattle / knock started coming from the motor. Keeping it below 4K eliminated the noise but we were unable to go over 60 mph. At stoplights, the motor would die. Again, no acceleration off the lights.

This persisted for 30 minutes (20 miles). We got to our destination, shut the car off for 4 hours and it ran fine all the way home.

This is the second time this has happened. Spent three days at the dealer and they changed the plugs (said we were driving too slow and it was loading up) and did several diagnostic checks / reprograms.

Anyone else had these problems??? Read on another forum of engine replacements (sometimes even that didn't fix the problem).

Its going back in tomorrow and I have told them I don't want it back until it'd fixed.

Thanks,

Chris

failed cat

Help me out. What is a failed cat???

failed cat = catalytic converter. The materials in the cat break down and clog up the flow of exhaust gases. This increased back pressure prevent the engine from revving very high.

go to another dealer if they can't diagnose this as a failed catalytic converter in the first place...

I had almost the same problem, next time it happens go straight to the dealer and have the service manager road test it with you in it. I bet the car acts normal when it sits over night and then gets worse when it is fully warmed up?? i just had a new engine put in.

The first time it was running poorly when I took it in. They had it for three days - lots of tests and downloads. Two months later and its doing it again.

Why did you have your engine replaced and how is it running so far ??

Thanks

Wouldn't this cause it to run poorly all the time ??

Thanks.

How many miles are on the car?

27,500 miles. All recalls completed, regular maintenance.

not as the honeycomb breaks down a portion can clog the outflow but then be forced out allowing the exhaust to flow again. it can happen without triggering a cel.

Took the car in this AM. Of course it ran fine on the way in and for the dealer. Asked about compression and the catalytic converter. Said he couldn't do anything unless it ran poorly for him. After I explained how unsafe the car it when it doesn't run and that he could keep it until it did something wrong so he could fix it, he decided to call Mazda.

The plan is to take the ECM (?) module out, send it to CA for a MOP 1 Reflash (???) and that is supposed to correct the problem.

I hope so. In FL we have a Lemon Law that I will pursue if it happens again.

Anyone else heard of this (the reflash) and if so, did it help?? I'll report on the lastest "fix" when it comes back.

Thanks for all the suggestions.

Chris

yes they have been sending someAT cars' pcms to MNAO in irving for a specific programming fix. apparently soemthing that cannot be doen by the tech in the feild with his equiptment.

The ECU in my 8 was reprogrammed but it did not fix the knocking issue. THe Mazda tech also decarbed the engine twice now. That cure only lasts for about a week. I was told that an engine replacement was the next step. I would think that checking the knock sensor would be the next step ,but I'll happily take a new engine.

you are driving too slow, go faster :)
maybe then, when you do drive faster and this still happens
they'll void your warrenty cuz u were driving too fast.... dealers... :p

Got the car back on the 21st. Ran fine for about 300 miles. Yesterday (the 28th) we were driving on the interstate at abot 78 mph with the cruise control on. The car kept slowing down causing it to downshift to third to keep the speed up. When we got off the interstate it died at the end of the exit ramp. Started it up and it had no power, engine knock at 3800 rpm, the same problems as before.

Called the dealership and was told there was nothing they could do right now as they were all going home for the day. Shut the car off, waited 3-4 hours and it runs OK again.

I am at wits end with this. I have read of "replaced engines" but (of course) my dealed has not heard anything about these problems - states that mine is the first - Mazda has no reports of anything similar, etc.

Planning on going to the dealer on Monday AM to see about a replacement engine, computer, car, money back (Lemon Law) or whatever it take to get this resolved.

Any suggestions ????

Thanks

definately sounds like the cat. Probably a piece of the catalyst that's to large to continue down the pipe. I'm guessing it gets jammed at the end of the cat after a while, and then falls back down while the car sits for a bit. If your dealer won't do anything without the problem existing at the time of service, you may have to request them to remove the cat and look at it. But you'll probably have to pay for it if that's not the problem. I would say you could remove it and look yourself, but then, knowing dealers, they might not cover it since you removed it yourself.

Took it back in this AM. Service Manager had called Mazda prior to my arrival. He said they told him to try to replicate the problem(drive the car) and do a compression test. He went on to say that they would probably replace the engine. I asked what was going on (what did he know that he wasn't telling me) and he would not elaborate.

Sucks that there is obviously an issue here and they (Mazda and the dealer) aren't giving me any straight answers. Interesting thing is that I suggested checking the Cat and he said unless they get a code for it they won't do so.

Not real happy with the whole Mazda experience............

This weekend also had a loss of power issue as well and car feels sluggish @ 22k miles. Gunned it and car surged - rpm went down slightly and car jerked. I have a MT though. From reading here and other threads in the past, I also suspect this is a cat problem. I will argue like hell if they say they can't replicate the problem. It is damn dangerous if you are merging into the highway and you are decelerating.

Very similar to mine except that it stays that way. The only way to "fix" the problem is to shut the car off for 2 - 3 hours. I would think they would troubleshoot all other possibilities (like the Cat) before just replacing an engine. Unless there is a known problem..............

Whoa! Whoa! Whoa! Replace the engine? Based on what theoretical failure mode? There was a lot of discussion about intermittently blocked cats above. Did the dealer ever look into that (small $$ for his service department) or did he just argue MNAO into paying him to replace an engine (big $$ for his service department). Sounds like the dealer is not too knowledgeable about cars and is taking a shot in the dark here.

IMHO dealers (and all auto repair shops) should justify every piece of work they do to your car. Also, IMHO, as the consumer you must be vigilent and provide oversite.

My dealer horror story - When my wife graduated from college I bought her a brand new `95 Pontiac Sunfire (they were kinda cool then, really). She loved the car except for this "ticking" sound the engine started making on cold mornings long about 10,000 miles. The sound followed the rpm of the engine and the car was well under warrently so I told her to take it to the dealer. They fixed it, but the noise came back some weeks later. Repeat twice more through the winter, then they ask if they can keep the car longer and give us a loaner. They never explained the root cause, but they seemed to have fixed it a couple of times so I figured I'd leave them to their work. After a week my wife goes in to check on her car and a lady at the service counter says, "Oh, that car. It has a lot of problems. They replaced the pistons." Now, I about blew some blood vessles over that. I wouldn't have felt any different if they had said they had to cut the car in half and weld it back together. The car had a measly 15,000 miles on it and the dealer's oil-change monkeys took apart the entire engine! I traded in the car shortly after that. They didn't void my warrenty, but they voided my faith in the car.

Whenever I take a car anywhere I always firmly explain that I am only authorizing them to diagnose, not to do make any fixes and that if they do any work without my authorization I will not pay. If I don't buy their analysis of the root cause of the problem I take my car someplace else even if I have to pay them for and hour's labor for "diagnostics' anyway. That hour's labor is cheap compared to letting a pack of morons monkey with the contents of my engine compartment.

yeah this is what i dont understand- tell them to look inside the CAT. if they say no its because they dont think mazda will pay them. why not? Mazda does pay for diagnostic time. besides which YOU could pay them the hour to look if it turms out its ok. but make sur eyou get to look at it. for that matter go to a midas or somesuchand ask them to drop it and have a look and let you look.

im quite sure your state law says they have to tell you WHY they want to do any repair that they say is needed.

Okay, rather than a rambling story (my friends know me for my stories) here is a succinct suggestion - try asking the service manager if you can speak to the service tech who performed the diagnostic work.

The tech himself may not have all the answers you want, but you might be able to get a discussion going between the three of you rather than sitting there being stonewalled by the service manager.

I think there is a lot more to the story than what I am being told. The daeler is saying nothing. On the one hand, if it fixes the problem, I'm good with it. On the other, I would sure like to know what is going on. As for the Cat issue, they won't do anything unless Mazda tells them to. I don't understand that either.

Waiting for a call from them (today?) to see what their next course of action is.

My 8 is getting a new engine because of knocking. I thought it was strange that they would give up so easy and replace an engine after only decarbing it twice and reprogramming the ecu to inject more oil. They did not even bother to check the compression. Hell, if I was a tech, my curiosity would make me check other components when no one was looking. ;)