check engine light
 

hey guys, im fairly new in the car area. I recently purchased a 2005 RX8. Shinka base model. the owner that had it prior to me didnt really take care of it. After about a month of having it the check engine, low coolant, and low engine oil lights all came on. I resolved the coolant and oil issues, althought a month later (today) the light is back on. im guessing theres a leak or crack in the hose. will be resolved tomorrow. As far as the "check engine" light, i do not know how to fix it. Most of the knowledge of cars that i have is all based off of youtube videos. I know how to change the radiator, water pump, how to do the oil change, and change break pads and rotors. I went to autozone and oreillys to get the system diagnosed. Two codes popped up, i do not know them by memory, but it was "solenoid fault" and "?cylinder misfire" How would i go about getting these issues fixed MYSELF. I do not want to go to a mechanic because i do not have the money for that. i have all the tools necessary to replace whatever has to be replaced, i just need to know how to access it and replace it. I was told that the solenoid is probably not installed correctly and it is messing with the vacuum line and causing the cylinder to misfire. ive also heard that its the spark plugs that are making the cylinder misfire. i do not know which is correct. please help me.

You've come to the right place.
First, about the oil, there is an oil injection system on these engines, which means you need to monitor the oil level and add some once in a while. The car will consume oil, and the consumption goes up the harder it's driven. This is by design.

For the misfire, if the spark plugs, ignition coils and wires have not been replaced recently, they should be replaced. These are the weak points on these cars, but if not maintained they can lead to engine failure. The replacements are easy to do on your own, check the DIY section.

For the solenoid, there are many, we need to know which one (which means we need the code). It's unlikely this is causing misfires.

The coolant light is either a real coolant issue, or a coolant level sensor issue. The solution is to replace in the second case the coolant overflow bottle, into which the sensor is built.

I would suggest the following items be checked thoroughly now that you bought the car:
- catalytic converter should be removed and inspected for damage or clogging of the honeycomb. Not doing so will kill the engine.
- ignition should be replaced as mentioned above
- compression test (for which you'll need a Mazda dealer, a regular compression tester will not work on these cars). This will tell you the state of the engine and you can make decisions from there.

Usually you want all this stuff to be checked before you hand over money for a rotary, but better late than never.

ive heard that Rotary engines are a hassle to take care of. I previously had a 96 Honda Accord, i learned everything about it and was able to fix it once an issue arose without having to take it to the dealership or another mechanic. but since its a "new" car for me i have to start from the bottom again and learn everything


ill reply with the codes a bit later. i do have another question though. As far as the Catalytic converter, i have read in multiple forums that if the car is under 80k miles the cat is under manufacturers warranty, how true is this? if thats the case i can get it without an issue. im still shy of 70k miles.

The cat converter warranty is good for 8yr/80k mi. You're unfortunately outside of that.

Have you read the stickies at the top of the new member forum? I'd recommend that for any questions. They cover in a lot of detail many things you should know about the car and the maintenance.

In the US the cat is covered 8yr/100,000 miles, but you are right, by years alone he is out of the cat warranty.

https://www.rx8club.com/new-member-f...t-here-202454/

RX8 Club’s recommended maintenance schedule, more comprehensive and proactive than Mazda’s schedule.
30,000 miles:
- Replace Ignition coils
- Replace Plug wires
- Replace Spark plugs
- Clean MAF (mass air flow sensor)
- Clean ESS (e-shaft sensor)
- Reset ESS profile
- Clean power steering connections
- Clean battery terminals and clamps
- Replace transmission fluid
- Replace coolant (Mazda FL-22 is highly recommended)
- Replace air filter
- Replace brake fluid (fluid in the brake lines AND the clutch line)
~$300 USD in parts if you shop smartly.


every 60,000:
...all 30,000, plus...
- Clean all chassis electrical grounding points
- Replace accessory belts
- Clean OMP lines
- Replace rear differential fluid
- Replace thermostat
- Clean / Straighten AC condenser fins
- Clean / Straighten oil cooler fins
- Inspect catalytic converter
- Clean / Inspect intake valving
- Consider / inspect all points in 90,000+ as well, many items fail early
~$130 USD in parts if you shop smartly.

90,000:
...all 30,000, plus any 60,000 not yet done, plus...
- Replace coolant bottle
- Replace radiator hoses
- Replace radiator
- Replace front O2 sensor
- Replace motor mounts
- Inspect clutch pedal assembly for flex / weld breaks
~$900 USD in parts if you shop smartly.
At 100k, anything original in the cooling system is really suspect and failure prone. It represents the biggest threat to your engine.
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The exact codes I got where

P0661 - VIS control solenoid valve circuit low input.
P0300 - Random cylinder misfire detected.


Also, thank you guys for responding and helping out.