i have no o2 sensor. i cut it off about a year ago. and now my car won't stay started, but it just started this. I cleaned my maf sensor and it didn't fix it? would a new sensor fix this problem? also saw someone just had this same problem and a new throttle body fixed it i don't have a spare laying around to try but wish i did. also don't really know anyone with rx-8 here or i would try theirs. any help would be appreciated or maybe someone has one for sale.

 

Please clarify: FRONT or REAR O2 sensor?

thanks.

 

Tell us about the other modifications you've done to the car. And how many miles, AT/MT.

 

oh sorry it is a MT with 105000 miles on it i have the k&n typhoon v1 intake and the cat coverter is punched out. those are the only mods that i am aware of. I bougtht it used and don't know if there is anything else done to it. and i think it is the rear o2 sensor it is the one that is in the cat or one that is in the midpipe if you have that. It also starts like a mother i have to crank and crank and crank on it and finally it is like oh you are trying to start me and then instantly it starts. it is like there is no gas going to the engine. it dies and doesn't start it has to have gas for these two procedures right? lol j/k

 

Please get your codes read.

You'll undoubtedly have a check engine light for the lack of the rear O2 sensor (although that code won't cause any problems, imho.), I'll bet there are other codes also present.

Go to Autozone, or someplace that will read your codes without charge.

Without this info, everything is just a guess; at your expense.

 

i have read the codes only code is missing o2 sensor should the car be running or no?

 

The rear O2 sensor is supposedly only for diagnostic (so they can fail you at emissions if your cat isn't working.) If it hasn't been connected for quite a while, I can't see why it'd suddenly start causing an issue.
Is there any chance that because of that code something else isn't showing?
You got gas in the tank? (jk..)
My guess would be fuel supply or ignition (eccentric position sensor?) I'm not sure which of these would cause issues without flagging a CEL though.

 

the rear o2 sensor does nothing for performance.. all it does is check for cat efficiency.

the front o2 sensor is the one responsible for trims/etc.

when was the last time you replaced your ignition... coils, plugs, wires?

 

a rotary tech told me that the o2 sensors "talk" with the pcm and adujust gas flow accordingly.

 

On a car with multiple exhausts, and therefore (for OBD2 cars) have more than 2 O2 sensors, yes, the front sensors "talk" the the pcm. On the RX8, the single front O2 sensor "talks" to the PCM.

 

Old plugs?

When did you last get new ones?

S

 

Typhoon ver 1 ? failed.

 

typhoon v1. fail, had that on my car when i bought it, actually made my car slower and run WAY worse! 2. Ide be guessing its your coils. 3. Get new plugs also 4.. 105k miles check your engine compression maybe its time for a new motor? and get the stock airbox with the screens as soon as you can you can usually find them on the f/s section usually around 50 bux. Just thinking back remeber my car dieing for no reason and hard starts b/c of the typhoon v1. car ran fine for awhile then all went to hell, and it was the intake put a stock airbox on it did the airbox mod and SHABAM! it was fixed lol.. my two cents..

next in this order i would.

1. order factory airbox and k&n Filter Or a better intake *search*
2. order new plugs
3. upgrade your ignition
4. if your still having problems then take it and get a compression test. or do option 4 first then go down this line.

 

here is diagnosis
codes p0037 -rear o2 sensor, p0300- random misfire, p0456- evap system, performed compression test kPa- front 1-4.2, 2-4.5, 3-4.1m rpm 172 rear 1-0, 2-0, 3-0, rpm 172. after charging battery front 1-4.9, 2-4.5, 3-4.7 rpm 190, rear 1-3.3, 2-3.4, 3-3.1, rpm 190 min. should be 8.0 compression. ran cat monitor switching test- failed- no switching because no rear 02 senor and cat converter punched out. 4 coils and wires -good, run oil pump metering test -could not finish test because of excessive smoke, tested secondary air injection shutter valves- passed vehicle will need an engine to repair concern will also need to have o2 and new cats for proper operation of new engine- can not verify proper engine operation because of missing components and added aftermarket parts. can not say vehicle being flooded caused the concern for engine damage. no o2 sensor and cat damage causes pcm not to operate engine at proper operation levels.

 

oK im not a genious but those compression test are super low... if im reading that right. u need a new motor... somone correct me if im wrong..

 

pretty sure youre right. BUT .. i dont see how you can have 0 compression on all three faces. there is no way to completely blow all three seals and crank it slow enough it build 0 compression..

 

Maybe they never tested the second rotor because they were going to have to rerun the test after charging?