yes

 

Will I have to replace the oxygen sensors as well?

 

I wouldn't worry about it yet...
Like I said, don't rush into things and lets take it one step at a time.

 

Sorry to bring back an old thread but I have the p2004 code throwing and I have cycled the key on and off. I can hear a motor running and then something click. Not sure if that is the sound I'm suppossed to hear but something is moving.

The code popped after the car sat for about a month. I was waiting on a replacement catalytic converter so I can get the car inspected. So i'm hoping the valve just had a build up of some kind that will go away with driving. Is that even possible or am I being overly positive?

 

Ok I am brand new to this forum so here I go…


I bought (for my son) my 2004 RX8 about 4 months ago. The previous owner only owned it for a couple of months. He is a shade-tree mechanic and bought the RX8 (which was not running) performed some repairs on it and got it running and then sold it to me. I bought it with a CEL (P0031) due to an O2 sensor that had been damaged when the previous owner bore out the Catalytic Converter.


Over the past several months my son has had the typical hot engine start issues as well as poor idle issues but everything went crazy the other day. He ran out of gas and just to get it running I put a couple gallons of low octant (87) gas in it. Well it would not start so eventually we popped the clutch and got it going. However as my son drove it home several issues came up. It refused to idle and was lacking power and ran rather hot. Since that time, the only way we have been able to start it is by popping the clutch. I did put several more gallons of the higher octane gas (93) in it but that didn’t help. I changed out the fuel pump thinking that might help but that didn’t either. Oh yea, to make matters worse, my son overfilled the oil (by about ½ quart) and on the way home it spewed oil out of the port on the fill neck of the oil (there is supposed to be a hose on there but it is missing?). I read the codes again and a new one now appears…P2004. I am not sure what to do and need help. I am about at the end of my mechanical ability and thinking I need to take it to the dealer or to a local mechanic shop new my house. I am concerned if I take it to the dealer they will want to put a Cat in it and fix the O2 sensor before they work on the other problems. Any help would be appreciated? I plan to call the dealer tomorrow to see what they say. Thanks….

Oh, one more thing I forgot...the Secondary Air Injection pump (I think that is what it is called) started whining really bad the same time all this other stuff happened.

 

Read here: https://www.rx8club.com/series-i-tec...-error-170404/

Is it possible you (or your son) revved the crap out of it under load? In any event, your APV is stuck open. I believe it cycles on startup so you may be able to just clear the code.

Check and clean your intake accordion tube and MAF (use MAF cleaner) if it's got oil in/on it.

Secondary Air is a separate issue and would only affect start up. After about 15-30 seconds it should whine right down. So long as it blows sufficient air to lean out your air / fuel mixture it won't cause a CEL/MIL.

I have a spare pump if you're interested. Takes about 20 minutes to swap.

Read the thread I linked to above and decide from there whether or not a dealership is worth the hassle. Most other mechanics won't be any more helpful.

 

"revved the crap out of it"...well after refilling it with gas my son drove it about 3 miles home. Upon arriving home is when we found the oil spewed onto of the engine. He mentioned that it was lacking power and he mentioned running the RPMs up i guess to try to get the power he normally gets from it. Once home the engine was very hot and I heard a hissing sound as if some antifreeze steam was coming out beside the battery box.

 

one more thing...I took apart the accordion tube today and found a little oil in the bottom of it. I cleaned it as well as the MAF sensor. I pushed open the flapper (throttle?) and did not see any oil in there.

 

I guess its possible he injected a shitton of oil into the UIM which could have caused oil to run into the APV or temporarily freak it out.

Pull the accordion tube and check it and the MAF for oil That'll be a good sign of whether or not you injested oil into the intake.

Clean the MAF with MAF cleaner (again this assumes you've got oil in the accordion tube), clear the code, and hope for the best.

 

let me ask a stupid question...will clearing the code actually cause the car to run better? If not, then I believe I need to take it to the dealer.

 

Clearing just the code will not do anything other than reset your OBD2 readiness tests to pending.

You may want to clear trims which I believe can be accomplished by pulling the negative battery terminal, stomping the brake pedal a bunch of times, and waiting 10 or so minutes before reconnecting it.

 

i heard about resetting the trims but have concerns...the guy I bought it from had the programmer to set the trims and that is what he did to get it running. If i reset them, I am afraid that things could get worse...any thoughts?

 

There's no such thing as a programmer that sets trims. We have programmers that allow us to rescale the MAF voltage to air table, adjust target fuel ratios, ignition timing, fan activation times, water and air to voltage calibration tables, throttle, OMP rates, suppress CEL codes, etc, etc via a flash process but we don't have anything that mucks with the trims. They build regardless.

 

"They build regardless"...are you referring to the learning capability of the car's computer? The reason I ask is because I was thinking that if we just kept starting it and running it a little each day maybe it would get readjusted properly...wishful thinking?

 

It might just be easier to let it retrim from zero.

No misfires / blinking CEL? I'm hesitant to tell you what I really think.

 

Also our programmers are persistent. Any changes we make to the various tables survive beyond resetting your trims / disconnecting the battery because they are literally burned into the ECU's EEPROM.

 

misfires...I don't believe so...it does do a lot of backfiring which I thought was too much gas in the engine. CEL is on solid...not blinking.

And please tell me what you really think.

 

too much gas == rich

could be because your MAF is dirty or broken which the car relies on for determining how often and long to fire your injectors.

could be because your compression is too low and fuel is just sloshing around inside one or both of the housings rather than burning....

 

so I'm thinking a compression test would be worth the $$. Question is...does the dealer do the best job of that or can I get my local car shop to do that?

 

a local rotary shop or a dealer. Regular mechanics will be clueless.

The dealership has a set procedure they follow.... something a monkey could do. They normalize the compression on each face of each rotor to a specific RPM and you either pass or fail.

 

ok...I think I got my answer...thanks for all your help!

 

good luck. Unfortunately, I don't think you're going to be happy with the outcome.

 

ok...I have done some looking into this issue and I need further guidance.


The local Mazda dealer is the only one I have found that will touch a rotary engine to do a compression test for me. I will cost me about $200. From that I will be able to determine if it makes any sense to put more money into this car.


However, I understand the lack of input from the upstream O2 sensor could be a lot of my problem and if I replaced that then I might be good to go. The cost of that sensor is $250.


So my question is, do I take my chances and put the new O2 sensor in or do I pay the $200 and get the compression test?

 

compression test first.

 

is there some guidance here on the results that I am looking for from the compression test (assuming the dealer's recommendation might not be trustworthy)?