GR3DDY,

Thanks! Hopefully cleaning the connector that Stealth talked about and cleaning the inside of the Throttle Body will do the trick. If not I will let you know.

If you don't mind, could you PM me the price of the throttle body? I just want to make sure I have enough cash.

mkztg

 

Gr3ddy to the rescue!

He's a reliable seller.

S

 

thanks stealth

pm sent

 

Yeah... let us know what you find... about 80% of the problems with this car seem to always be coils+plugs... this is stupid, but its interesting to have something new that could be a number of different things.

 

Vyn,

Its strange that you mention that. About 2 months ago I replaced my spark plugs, wires, and coils. All brand new. I'm headed out in a few to work on it. I'll post back whatever I am able to find out.

mkztg

 

The short story is: cleaning the throttle body didn't work, neither did disconnecting and reconnecting the sensor plug that Stealth talked about.

The throttle body did have quite a bit of carbon on it, I only wish I had remembered the camera so I could show you guys. I also found out that the two hoses connected to the TB are not vacuum hoses like I thought.. I sprayed a little bit of coolant everywhere.. Not a problem once I figured that out.

I did an oil change while I was at the shop and came home. I started to think about the pedal sensor that Vyn talked about. While we had the intake off at the shop we turned the car to the "on" position and the butterfly valve actuated but did not respond to the gas pedal. This got me thinking some more and I found the sensor connection on the gas pedal and disconnected / reconnected like I had been doing to the throttle body. This allowed me to start the car the same way as I had been doing by disconnecting/reconnecting the sensor on the TB.

Now I am a little confused as to which part could actually be bad. The gas pedal sensor or the TB?

If you recall, the translation of the German fault code it was: Description - P2109
Butterfly valves - / driving pedal position - Sensor A: neutral: Function

The American description of P2109 is: TP (Throttle position) sensor minimum stop range/performance problem.

I am starting to think it could be the gas pedal sensor. The gas pedal is the throttle... Any other opinions on this? Thanks in advance and I have posted a few more pics of the TB sensor and the gas pedal sensor just for good measure.

mkztg

 

I apparently had the same CEL code or a similar one before I had the PCM reset...a bad battery I thought was triggering it...as soon as I return home, I have to work on the car to figure out what was going on...

So basically...



EDIT: See the dyno thread...

https://www.rx8club.com/west-rx-8-forum-34/socal-tuning-dynoday-mazdamaniac-jan-24th-162796/page16/

And I'll keep you posted on what I find...

I'm returning home next Sat Jan 31st, and probably take it all apart Sat/Sunday

 

eviltwinkie,

Yes please let me know what you find out. Hopefully I can work out a solution before that time for my 8. What is so frustrating in my particular situation is, the only thing I did prior to this happening was to fill up with gas and run the car through a local car wash (including an under-body wash).. Shortly after that the CEL tripped and the all the problems started.

Good luck to you!

mkztg

 

If you at the stage where you start buying sensors or parts, the first 'part' you need is a code reader/resetter. - something like ebay item #190281419538 (sorry, links not allowed)

Best investment you'll find for getting rid of code problems.....

You need one that will read CAN codes, they are cheap.

Might be as simple as 'reset code' and it never comes back!

S

 

Stealth,

You are the 5th person to tell me I need a code reader today.. It must be true

My wife told me - If you need it then get it... That is a good sign too..

I looked at what you showed me on ebay, do you think this item: Amazon dot com search " Crescent USB OBD2/EOBD " would also work? Not asking for a guarantee just your advice.

Thanks.

mkztg

 

Not that one - you'd need a laptop with it - get a bigger one with it's own display.

S

 

Thanks! I'm waiting on a reply from the one you told me about so I can make sure they will ship to my APO address.

mkztg

 

I just got a scanner off ebay - it should be here by the first part of next week... I started reading some of the related threads and came upon this one: https://www.rx8club.com/series-i-tech-garage-22/help-accelerator-pedal-position-sensor-p2138-164781/

It looks like sunsilver had the same indications I had but with a different fault code. Based on this I have to lean toward the throttle body being my culprit.

Gr3ddy - I will PM you in the next day or so to make the arrangements for the throttle body you said you could sell me.

Thanks so much for all your help so far. This isn't over yet - as I know more I will post more. If you all have any more ideas or thoughts please let me know.

mkztg

 

man ill ship you both the throttle body and the gas pedal assy. Then whichever works you pay for the other you send back. No sense in buyin one, not working then buyin other, then waiting forever

 

GR3DDY,

Man, you are great! I appreciate you helping so much. I'll PM you the address. Its hard to go wrong when you are offering me to ship me both and send back the one I don't need and pay for the other.

mkztg

 

mkztg you got PM

 

The parts came in the mail today - I will install tomorrow and post an update.

mkztg

 

Awesome!
Good luck and I can't wait to hear what the final verdict is.

 

Ok, I swapped out the throttlebody first - it wasn't the easiest part to do first but I thought that was the real problem.

- Same fault...

I left in the new TB and swapped out the pedal

- Same fault.



Thank god I got my code scanner on the same day as the parts or I would really be frustrated.

The only thing I can try now is swap the TB back with the original and leave the new pedal in to see if it throws the same fault. Beyond that - I am stumped.

Any thoughts on what else it could be if that doesn't work? I'm headed out to do the TB now. I will just be late going back to work.

mkztg

 

Wow... not much else would cause this error code.
Try swapping the drive-by-wire relay with a similar relay.
Its in the fuse box in the engine compartment.
Under the lid, you'll see the fuse & relay layout.
Its labeled EVT

 

Thanks Jon,

going out to try that now.

bottom line is: replacement TB and old pedal = fault.

replacement TB and replacement pedal = fault.

old TB and replacement pedal = fault.

I hope your idea fixes it. - I'll brb

mkztg

 

Looking at an electrical diagram, there is also a ETV 15A fuse in that same compartment.
Might as well make sure the fuse didn't blow.
I'm really stretching it now.

 

I think you may have broke the code on this though...

If you recall, I would have to disconnect the electrical connector on the TB to clear the fault so I could drive the car.

Pulling the ETV fuse and putting it back in does the same thing - it fixes the fault long enough to at least drive it.

The EVT is a light blue color. The only other ones that look like it are the Fuel, Circuit and the the EGI.

Is it ok to swap with those? I wouldn't want to kill something else troubleshooting this.

I see the 15A ETV you are talking about - I will pull that and check it. brb..

PS.. you rock for this real time help.

mkztg

 

I'm checking the electrical diagrams now on those other blue relays... but I'm pretty sure you'll be OK to swap with those.

 

I checked the 15A ETV fuse and the connectors looked a little corroded but not bad. The fuse wasn't blown.

This is frustrating.