EDIT: Sorry being terminally dumb. The original codes were "too rich" and an ESS error NOT a misfire (although it felt like a misfire). Sorry tired and dumb :-)



OK sorry to be a newbie after two years but....

Having had two new engines, couple of days ago she misfires briefly and then 12 hours later persistent CEL.

Long story short dealer has her for 36 hours and lots of back and forth with Mazda technical. Eventually they say it is a fuel injector staying open too long.

So they say install four new injectors.

I checked the codes before I took it in (sadly did not write codes down).

Started with misfire AND fuel trim (?) too rich. The next day a third code got added after I had driven 6 miles to dealer - something like "Fuel mix too rich AFTER the cat" (my emphasis). That worried me as that looks like could need a new cat if not careful.

Having looked at the workshop manual the diagnosis process looks horribly tedious and therefor expensive to find out which injector is staying open so long.

These guys are very helpful but do very little Rx8 work and they are the ONLY Mazda dealer on the island ... so unless I DIY (which I do not want to on this one) I have to go with them so....

QUESTION NUMBER 1 - Does the diagnosis make sense/sound right. They have put in hours on this with lots of calls to Mazda tech. They have also said they will do the diagnosis for free (as I have had so many nightmares with them/the car).

QUESTION NUMBER 2 - Now don't shout. I have read lots on here and enough is enough. WHAT DO WE THINK ABOUT REMANNED INJECTORS?

Dealer price around $275; online OEM $160ish, remanned $50ish. This car is such a money pit for me that I HAVE to get rid soon.

I have:

05 2005 Mazda RX8 Fuel Injector - Fuel Injection - Beck Arnley, Denso, GB Remanufacturing, Original Equipment - PartsGeek

Fuel Injector - Auto Parts Warehouse

QUESTION NUMBER 3 - Have just got the parts list back from my friendly dealer. Specifies N3H1-13-250A and N3H2-13-250. The second one is mentioned as "AUTOMATIC Trans - in Manifold". Now this is perhaps the most important and most dumb question: are these 250s different for manual and auto and, as the 250As don't mention automatic are they the same on both models.

Grateful for any wise rapid replies.

Want to order today if possible and shops are closing on the East Coast as I type.

I WILL be doing more research myself but running out of time.

Thanks in advance.

Steve

 

The difference between the auto and manual transmission is the number of injectors, and their size. Series 1 cars could be either 4 port (auto's) or 6 port (manuals), and the total number of injectors varied depending on the engine (a total of 6 injectors I believe for the 6 port engines, and the size was not the same; 2 were bigger than the other 4 but I can't recall numbers, sorry).

As for reman injectors - I have no personal experience with them, but I don't see why not. I would go OEM, but if this car has been a money pit that your looking to get out of in the near future reman shouldn't be a problem. But like I said, no personal experience with them.

Misfires can make the cat go bad surprisingly quickly. So provided you were misfiring previously, the inappropriate post-cat O2 readings aren't terribly surprising.


Best of luck to you as you sort this out.

 

Its all a matter of flow... So long as you don't uncap the cleaned injectors they should flow at their original rating.

You should receive before and after flow test sheets to validate this.

If your cleaned injectors by some freak of nature flow considerably more than they are rated you will run into rich conditions. Likewise less will put you into lean ones.

 

it's highly doubtful the injectors have any problem at all, possibly even a simple failed O2 sensor causing the trims to lean out and causing the misfire. is the fuel mileage horrible or lower than usual? if not then it probably isn't actually running rich.

for the ESS i can't say what the problem is. i have had the same issue pop up on my car but it doesn't appear to be common. it only happens in hot weather during summer, which could simply translate to a faulty ESS sensor, but in my experience they literally never failed in the FD3S and the sensor is virtually identical in construction(either it is the same or it might be interchangable, i plan to see if it is but just haven't checked yet).