CRAZ8

I just had my engine replaced and was in the process of breaking it in. I have kept rpm under 4k for 1000kms and now I am increasing revs to 6k for the next 500kms, then it will be all bets off.)
I am presently at the 1300kms mark and today while I was on the highway, revs around 4-4500, the oil light came on. I immediately pulled to the side of the road and shut the car down to check the oil levels (which I often do). As I suspected the oil was only down about 1/4 litre, no even close to being low, so I added 1/4 litre to top her off and when started up the light was gone. I will be taking it to dealer tomorrow. Any ideas on what this could have been?

CRAZ8

Just got back from Mazda. Checked oil levels everything fine, no leaks. Did a complete diagnostics on engine, no issues were detected. It must have been a hiccup in computer (or I have a ghost.)

Loki

iTrader: (1)

I'm pretty sure the oil light doesn't talk to the computer, it's a direct wire from the oil pressure sensor, and it triggers when oil pressure is low, not oil level. So whatever it was, either the sending unit is lying to you, or you actually hit low oil pressure for some reason.

Did it just blip on and off, or was it on until you shut the car down?

infiltr_eight

@Loki: You're wrong mate ... the oil light (oil can symbol) is the oil Level sensor ... the oil pressure sensor goes to the oil pressure gauge in the gauge cluster.

Early Rx-8 models had a faulty oil Level sensor ... maybe it's a 2004/05 oil pan on it with an old sensor. The faulty sensors came on when the engine was hot and the oil Level was nearly Maximum and only shut off after engine restart.


@CRAZ8: Next time u have the Problem .. stop ... shut down the engine .. wait 3 minutes ... restart the engine ... if it's gone it's your oil Level sensor in the oil pan.

edit: sorry for my bad english

Greetings
Thomas

StealthTL

iTrader: (1)

Here's a man who knows his RX-8 history!




.

ken-x8

So is the oil level sensor integral with the pan, the way the coolant level sensor is integral with the coolant bottle? There's a TSB that covers the oil light coming on when it shouldn't in early models, and the fix is to replace the oil pan. I've always wondered what it was about an oil pan that can do this...now I know.

Ken

infiltr_eight

@ken-x8: You could Change the oil Level sensor itself while keeping the old pan but Mazda decided against it IMO mainly because labour time to Switch the old parts in the new oilpan or put a new sensor in and scrape the sealant off is greater than the Price of a complete new pan.

Greetings
Thomas

CRAZ8

Yea my oil pressure gauge has always remained normal, and oil levels are always good. It must have been the sensor.
@Infiltr eight thanks for the information.

CRAZ8

Today my oil light came on while on the highway, so I pulled over, shut the car down for 3-4 minutes, started it up and light was gone. Good call infiltr_eight.
So I have a bad sensor... Is it ok to keep driving my 8 with the bad sensor? (I normally keep a close eye on oil levels anyway.)
Or will this eventually damage other parts??

infiltr_eight

@CRAZ8: I drove the 8 from 2004 to 2013 (had a bearing failure due to bad fuel Dilution on the original engine then) with the bad sensor. As Long as u check your oil regulary .. it's no Problem.

My Problem was i always stopped and checked the oil .. it came on about once a month ... mostly after Autobahn drives....

Greetings
Thomas

CRAZ8

Thanks for the information Infiltr_eight, very much appreciated.

CRAZ8

I had the oil light come on again today after a bit of "spirited" driving.. I stopped on side of highway, shut her down for 3 minutes, started her back up al was normal again. Is it ok to keep driving when light comes on or should I shut it down to reset immediately (if I know my oil levels are good)?

CP2

This was the most recent thread I could find on this.... I've had similar oil light troubles. I know that the original defect applied to very early cars, but mine's a 2008, with about 69k miles on it. I've had the oil light come on at random times despite good oil level for the last 2500mi or so. I thought it originally due to using a large Purolator oil filter instead of a stock sized one. So I replaced it with a standard size filter about 1500mi ago. I mostly take my '8 on fairly short drives, but on longer drives, especially extended at highway speeds, the oil light comes on. It generally goes out again when I slow, but can be on/off seemingly at random. The oil level has been fine, I check it each time.

Is there anything else it could be besides the sensor in the oil pan? Since I still have a little of the 8yr/100k warranty remaining, would that possibly still be covered if I brought it to the dealer?

CRAZ8

Oil pan/sensor is not part of the extended warranty, it is part of the 3yr/60k bumper to bumper warranty. Extended warranty only covers engine core.