Dylanliam1

Hi everyone I am a new member and wanted to see if anyone has experienced the same problem as me.

I have changed my 1 bank oxy sensor replaced my cat put a new fuel pump in and cleaned my maf sensor, also had compression tested and is good.

What happens is after driving for a while it will cut out and will die but as soon as I turn the car off and on it will be fine for 10 minutes or so and will play up again. Had it in mazfix in Australia and they said it was the fuel pump as the pressure was low 28psi but since new pump and sensors are in still experiencing the same issue.

Please help me.

200.mph

iTrader: (9)

fuel pressure should be ~60psi

Dylanliam1

They said the new pump is operating at 62psi but after one day it started playing up again!? I am scratching my head. I'm going to drop it back again next week and see what they say. Could it be the ssv or build up of carbon somewhere?

04Green

iTrader: (1)

How old is the ignition?

What you describe, I would look to fuel flow first, but could also be something strange with ignition.

How much fuel in the tank? How did the swap? Did they just do the pump, or the whole assembly? There is a filter sock that could be plugged up.

Will it do it at idle, or just running? If you run it harder, does it do it more often?

Dylanliam1

I haven't changed the ignition I'd say that is still original it has done 140000 km not sure how Many miles that is. It idles ok. They replaced the whole fuel pump assembly and sensors. The old filter was full but they put in a new one... Could be electrical I'm thinking...

Williard

iTrader: (18)

If your ignition is that old you really need to replace it.

Everything, Coils, Plugs, Wires. Every bit.

Change that ASAP! Im actually amazed you can start it...

After thats done, come back and report the results.

140,000 Kilometer Is just over 86,000 Miles

Also, so you know its suggested to change the ignition system between 20-25,000 miles or 35-40,000 Kilometers

Many of us chose to purchase BHR's solution.

The "C" revision coils will work just fine if you choose to not spend that amount of money.

Travis

Dylanliam1

Thanks Travis I have done the coils last week and have the upgraded c coils from mazda. Also done plugs and leads. Is it a separate ignition module you are talking about?

Mysterion

Which part of the post are you referring to? His reference to the BHR?


Just had a thought. Other than a CEL, was the car running better/more reliably before the O2 sensor replacement?

Dylanliam1

It was worse before I changed the o2 sensor. We down loaded the readings with a scanner while it was running and it wasn't reading correctly so just done it as precaution. I first thought it was the cat so changed that to a hi flow as it was partially blocked. Changed the o2 sensor still played up. Then coils still played up. Then fuel pump,was better but after driving a while still plays up. Unless I switch it off than on. That will buy me 30 mins of driving. Also left the fuel cap loose still played up as I thought it was a breather. Changed plugs cleaned maf, still playing up. Has good compression also just had tested last week. I am at a loss as I have replaced everything I can think of with new parts. Seems to do it when it is heat soaked after an hour driving. Also reset the dsc computer also. Still no change...

infiltr_eight

After installation of the new fuel pump did you test the fuel pressure regulator in the fuel rail?

I would also check the complete ignition system (cables, plugs, connections, wires, coils)... maybe one or more things are failing under heat.


Greetings
Thomas

04Green

iTrader: (1)

So.

runs, dies, reset car (on and off), and it is fine for 10 or so minutes. Is that a hard 10 minutes, or does the time vary, say, with load?

If all it takes is a power off and on to get it back, I am thinking ignition is fine (it would get worse shut off for a minute without air flow). Noting mechanical would behave that way, nothing could cool down fast enough to make a difference. Your lose gas cap idea says that is not the issue.

The evap system really does not work in a way that I know of that would cause the problem.

Does it stumble and die (fuel delivery ish), or just plain quit (ignition ish)?

Only thing I can think of is infiltr's suggestion on the fuel pressure regulator. and, it is a really good suggestion. If it is plugged, or partially plugged, it could be costing fuel pressure at the injectors after a time. Do you have any type of data recording device that could monitor fuel trims and let you know if it is struggling to maintain the mixture right before it dies? If not, I recommend the ultra-gauge. It is pretty cheap and will show up to 8 things at once. It is something you leave in the car.

Dylanliam1

It is like the fuel will cut out like you are saying. It will splutter and miss than die. Than I will shut it off whilst driving and turn back on and it is fine. I put octane booster in with the fuel yesterday when I filled up and didn't premix and drove for an hour this morning and it was running fine. Revving out to the limiter every gear. Climate was cooler today though that was the only difference. I like your idea of the fuel rail pressure I will have to get that checked. I want to go for a longer drive on the weekend and see if the additive helped?! It did come up with a code cu0073ff on my friends scanner but it was non Mazda and I couldn't find anything relating to this code. Said something to do with the CAN. Do you guys know what this could mean? Also a while ago a fine young lady said she put a tampon in my fuel tank but the tank inspected and there was nothing in there. Were a few fibers on the bottom of the old fuel pump...

Legot

iTrader: (1)

Not gonna lie, that's hilarious.

Code 0073 is an incoming air temperature sensor in certain vehicles, do you have a JDM rx8? They're been known to show different route codes than other markets. Have you checked/cleaned your MAF recently?

Dylanliam1

To be honest I'm not sure if it is a jdm. It is a little different than most rx8s in Aus as it has black interior most have red and black. I do need to get some proper cleaning agent for the maf as I have only really cleaned the air flow sensor on the and I have a k&n filter but I only lightly oil it. Maybe that could be the problem... I will get some cleaning product and give that a go. I was told by mazfix that he thought that was what the code was also, but they replaced the fuel pump and didn't check the maf sensor. The tampon in the tank wasn't funny at the time but thankfully she is out of my life lol.

infiltr_eight

Another guess would be a stuck open Purge Solenoid ... to Test it just remove the U-Tube at the UIM and plug both holes and see if u still get the same error. If ist stuck open it can lead to very rich AFR conditions which also can make the car stall.

Greetings
Thomas

Dylanliam1

Hi everyone so I clean the maf again with crc air flow sensor cleaner, cleaned the crank sensor which was very dirty and also am running octane booster and it seems to be better now. Went for a long drive and had no missing etc so time will tell if the problem comes back. Thank you all for your help! I will keep you posted.