Hi Guys

I've had my Rx8 for a year now, am based in the UK and have been on the UK oc forum for a while, but the other day my car droped out on me whilst driving, It was sounding very rough to start with and didn't want to accelerate, then just cut out completely. I pulled over and tried to start her but she wouldn't go, called out the roadside assistance and they pluged in their error code reader which came up with "missfire Cylinder 1" so his suggestion was coils and he couldn't get hold of any so towed me home.

I replaced the ignition coils only 6 months ago but with cheap eBay ones, so I went and bought an official Mazda one (100B part number) swaped this out in turn for all of the current ones with no difference to the running of the car at all. HT leads are brand new Blue magnecores, and sparks were replaced at same time as coils only 6 months ago.

The car runs but is extremely lummpy and undrivable. I pulled out the spark plugs and cranked over the engine and can confirm that they are sparking bright and blue, there is lots of white smoke from the exhaust when it is running so assume that is the unburnt fuel from rotor 1 so it cant be a fuel flow problem. The only options I can think of now are rotor tips on rotor 1 are so worn that there is hardly any compression at all , or that the eccentric shaft position sensor has broken and the timing of the spark is therefore out.

Any of you guys got any ideas what it could be? Any help would be much appriciated.

Many thanks
Scott

 

how many miles on car? any mods? do you still have a cat? does the white smoke smell sweet? any oil in the intake tube/on air filter? when was the last time you cleaned the maf and ess? what did your plugs look like when you removed them

 

56000 Miles on car, no mods, standard 231ps model. Brand new cat 4 weeks ago. Tbh couldn't tell you if the smoke smells sweet, no Oil in intake tube/Air filter, always very carefull not to overfill with oil. Cleaned maf maybe 2 months ago. Spark plugs didn't look too bad, bit of coke on them, cleaned them up and put back in tho.

I've purchased some seafoam also, will it be okay to run this through only running on one rotor?

 

Cleaning iridium spark plugs often ruins them. Change them!
Check the leads' connection (l1,t1 since you're getting a misfire) and that the harness is correctly installed.

Also reset your eccentric shaft position sensor while you're at it.

 

How do I reset the shaft position sensor???

 

You reset it by stomping on the brake pedal 20 times in 8 seconds with the key in the ON position.
The gauges will sweep to confirm that the procedure was performed correctly.

 

just to clarify only the dummy oil pressure gauge will sweep when properly done. not being a dick 50 just want to keep it clear and help get one of your european bros back up

 

Okay so just standard ECU reset procedure, have done this before a few times with no sweeping of the dials, someone on the UK forum said they may not sweep depending on ECU firmware status. Also I confirmed the spark plugs are actually sparking nicely by pulling them out and earthing them on the engine block and cranking the engine. All looks good even after my cleaning of them, only used a small wire brush, do they really need replacing?

 

You're absolutely right, no need to apologize

 

They may now, since you used a wire brush on them. Use only plastic-bristled brushes to clean spark plugs.

Also verify you have proper fuel pressure (57 PSI+).

 

purchased a cheap piston engine compression tester and it showed that rotor one had no compression at all compared to rotor 2. So the car has gone to be rebuilt, gunna take 2-3 weeks and cost £3k, all fun and games, this is the risk we run having these cars I guess!

 

What kind of rebuild are they performing for that amount of money?

 

Well it's being done by a Rotary Specialist here called Hayward Rotary. They seem highly recomended by the UK OC, and £3k seems to be the accepted norm here. I can imagine it would be a whole lot worse had I gone to a deaer.

 

If they include new or like new housings £3k is not a bad price for a rebuild itself.

 

Not certain they're putting new housings on tbh, but I am going to check up on the progress on friday so will ask then

 

Saw the car yesterday evening looking very sorry with no engine under the bonnet. But the strip down was done, and the compression issue was quickly traced to two cracked apex seals. The guy said I will prob need 1 new housing on the rotor that had the cracked tip and possibly a new side plate or whatever you want to call the end part, but that is all included in the price but they will be replaced with good used parts. The temptation to get it ported while it was in bits was very strong but money was for too tight for me to warrent it. anyways, here are some pics I took from my visit: