help with codes

[mitmaks]

what was the problem with sensors?

[mikeinaus]

they threw codes and didnt work properly. while i dont believe in paying $300 a sensor at the dealership, i do highly recommend buying oem for o2 sensors. denso is the oem manufacturer for mazda. you can buy there oem sensors for like $60 i believe, or there universals which i have and highly recommend for about $30. check denso's webpage for the part numbers you want.

[mitmaks]

I was reading repair manual and it says to check water thermosensor and ECU, doesn't even mention O2 sensors.

[mikeinaus]

you have codes 17 and 24 which are for o2 sensors. when mine were bad i was getting misfiring at lower rpm and higher loads. have you isolated what cylinder is misfiring? is it random like once or twice while accelerating or is it more constant where it will happen while its idling?

your not giving us much information to go off of so we cant be very helpful...

did you do a fuel volume test? or a max pressure test? just checking if the pump can make pressure isnt the whole story. pumps can fail and still make adequate pressure but cant supply enough volume.

coolant temp sensor shouldnt affect idle like that, but you can try and disconnect it and see if it gets better.

[mitmaks]

it runs great at idle. It's when I'm driving it it seems like its lacking power or it stumbles. I checked and every cylinder is getting spark, also fuel psi is where it should be.

[mitmaks]

Where is the rear O2 sensor plugged into? I tried tracing it laying underneath the car but can't see where it goes.

[mikeinaus]

i *believe* its on the same line as the egr plugs?

btw bad o2s will lead to lack of power, bad fuel consumption and poor performance. they wont however affect idle, starting or cause any weird problems. i honestly believe your problem is your o2's. theres no point in testing other things until you replace them. your car is telling you they are bad, but you dont want to listen?

[mitmaks]

replaced o2 sensors, still same issue

[mitmaks]

Any ideas? I'll try another set of fuel rails with injectors

[Juans_93_MX3]

it runs great at idle. It's when I'm driving it it seems like its lacking power or it stumbles. I checked and every cylinder is getting spark, also fuel psi is where it should be.

Thank god for your post.
I just realized why my car isnt turning on and why I am not getting fuel.
I disconnected the Fuel System relay thinking it was the automatic tranny computer.

[mitmaks]

So I've replaced disty cap and rotor and it doesn't seem to stumble anymore. It still hesitates a bit on acceleration until I reach ~2K rpm. Going to replace fuel filter this weekend.

[mikeinaus]

how old are the plugs and cables?

[mitmaks]

Brand new ~less than 2K miles.

[mitmaks]

So I've been driving it just fine. It's just weird that after all this hassle it was just a simple disty cap/rotor. I guess next time I'll just start out with small inexpensive cars. Never trust CEL lights, usually problem lies somewhere else.