Just want to say that this problem is now resolved but I still want to get into the why to avoid future problems.

Quick background
04
2nd engine at 96k
Currently at 127k
Less than 100 miles in the past 18 months (0 miles in last 6 months)
Problem: dies at idle once warm and idle RPM drop from 2k to 900
Codes: 0171, 0410, 2096 (all pertaining to running lean / air injection)

The car has sat for quite a long time due to a deployment then a decision to sell that never happened. Recently I have decided to keep the car and I am getting it back to perfect shape. I had to replace the battery and when I did this I noticed a cracked open hose coming off of the intake so I went ahead and replaced it.

Now after this it would start, drive perfectly, but idle poorly and stall out. So I researched the codes and they seemed to deal with the car running lean. I went though and did a visual inspection for any kind of vacuum leak from a cracked line or poor fitting but didnt find anything. I cleaned the MAF sensor, intake, etc but everything was clean to begin with. This didnt fix the problem. I then put in fuel injection cleaner into half a tank and ran it out for about 50 miles, didnt help.

Finally I did the E shaft reset with the brake and that seemed to clear it up, 30 miles of driving with no issues on idle anymore. Now I just want to know what was the original problem. I dont remember the car running poorly prior to setting.

So could the car just need to relearn after replacing the cracked hose coming off the intake to get the fuel mixture right? Or is there some other issue that caused it and is it possible for it to come back?


BTW, I have coils, plugs and wires on the way (plugs replaced 31k ago, coils 50k ago, wires never).

 

Is your 31k and 50k thousands of miles or kilometers? If it is thousands of miles, then you are way overdo for plugs (every 15,000 miles or so), coils (OEM coils every 30,000 miles, BHR coils should last the lifetime of the RX8) and wires (same time as you replace coils). Poor or failing ignition can lead to a snowballing of many problems.

I see you have 2577 posts here. I am sure you have come across all the good info on proper maintenance of your ignition before. Ignore your ignition health and risk many more troublesome issues with your RX8 including a dead engine and cat. Best to you in getting it all sorted out now.

 

I know proper maintenance however I have never seen 15k on plugs, always 30k which I have always done. And coils isn't necessary every 30k if they pass a spark test and a benchmark test, through all three terminals, for resistance (which they did when I last replaced plugs.

I have no power loss, misfires, slow starts, issues of any kind which indicates no issues with the ignition system, I am simply changing it out for precaution.

But back to the original question I had, did my car learn to operate with a cracked air intake hose and need the e shaft sensor reset to change the parameters back even after I replaced the hose?

 

I would get a proper vacuum leak test done (smoke machine, etc). But it could be many things.

Engine----> Symptom Troubleshooting

http://foxed.ca/rx7manual/2003mazdarx8/

 

Thanks for the link 9k. I've seen it before years ago but I didn't have it saved anymore

 

30k is really pushing it for any rotary spark plugs guy. (I know something about this. I have driven over a million rotary miles on street and track in over 41 years and seven RXs) Did you pull the plugs and look at them at 15k. Try that next time ok. No matter if your coils passed your spark test, why not upgrade to the BHR coils and wires and actually save yourself some money and worry over the longrun ? Just a suggestion.

 

regarding question...

If you were running lean, the computer may have trimmed way rich to compensate. also, could be crap on e-shaft sensor. you could have had 2 competing problems. It seems the ECU will go to considerable lengths to keep the engine running, then fall off a cliff. cleaning everything and resetting, and letting it re-learn the idle will fix a lot.

 

It could be a lot of things, taking wild guesses doesn't help to find the issue. It has to be properly troubleshooted. Not everything wrong with an RX-8 can be fixed by doing an NVRAM reset, replacing coils/sprakplugs/wires, cleaning the MAF, and cleaning the ESS.