Adonnis248

HELP. Recently acquired a 05 rx 8. It was driving fine. Although it lacked power until about seven grand. Idled rough and wanted to die unless I fed it gas eventually I could start it and let it idle on its own but after about twenty minutes of driving I would still have to stay on the gas at lights ( oh so fun on a downhill as well sitting left foot brake and right foot gas until light changes and could go in gear). Then drive home from work went inside for about thirty minutes and then wife and step son wanted dinner and when I went to leave it wouldn’t start and still won’t. Hoping I don’t have to rebuild. Any info suggestions or ideas would be greatly appreciated. My 86 hardbody from Japan isn’t this hard to figure out so why is it such a pain in the ***

200.mph

iTrader: (9)

lets start with the basics. mileage, transmission, any mods, what maintence has been done, any recent compression test?

Adonnis248

Mileage is about 150k. Seems like it’s on coil overs with a cold air intake. Have not really had time to get into it yet due to family life. It was also lowered. The guy before me bought it from original owner who did some work to it and then the second guy bought it to help a buddy and barely drove it.

Adonnis248

Six speed as well sorry

200.mph

iTrader: (9)

how long has it been since coils wires spark plugs were replaced? not starting when hot is a sign of low compression. its also possibly flooded. can you opst a vid of it cranking? how old is the battery? what size starter is in it? the idle issue could be a million things, i would start with the easy cheap stuff like cleaning the maf, ess and doing the 20 brake stomp. the no power until 7k could be a dirty ssv

honestly need a lot more info and you should try looking at the series 1 troubleshooting sub forum. every question about these cars has been answered many many times

Loki

iTrader: (1)

Depending on what intake it is, that could be 50% of the problem.
The not starting sounds like it might be flooded. I have the feeling the car has been neglected/abused, so let's start with basics.

Are there any OBD codes? Those would be a clue, if any.
What intake is it? Pictures always helpful if it's not easily identifiable.
How old are the ignition coils, wires and spark plugs? If over 30k miles or unknown, replace the lot.

My guesses based on provided info: stalling at idle and lack of power is either vacuum leak, poor quality intake (very few are better than the stock one, most are a downgrade) which leads to unreliable MAF readings, and/or stuck intake valves not properly configuring the intake in different regimes.

To get it to start, try the deflood procedure and/or pull the plugs to dry them out. You can google it but basically hold the gas pedal to the floor, crank for 8 seconds, pause for 30, repeat 4x, on the 4th attempt slowly lift the gas pedal while cranking and modulate if you hear it starting to catch. If not successful, rest the starter 10 mins and repeat. It may take a few attempts.

Report back with codes and more info, and results of deflood attempts. Healthy RX8s don't flood, but if the ignition is weak, they can.

Another thing: did you have compression tested before purchase? A 20 year old rotary is a 20yo rotary... May want to look into that before spending a ton of money.

May want to read through the info at rx8help.com

Adonnis248

I am currently on my way to take wife to dentist. I will look into everything and get back later today or tomorrow about the info you asked it has a coolant light that doesn’t go off even when I fill res to top. Check engine light stays on and auto light level stays off with trac control light as well. Can’t think of any others right now.

Adonnis248

Video of dash and trying to start

200.mph

iTrader: (9)

first check the battery terminals, they are a well known problem. clean them and make sure they are tight. its not cranking so start with the batt first. the coolant light is another well known issue, theres a sensor in the expansion tank that gets gunked up. you have to replace the tank to solve the issue or unplug the sensor which i dont suggest w/o an aftermarket temp gauge

Loki

iTrader: (1)

So it's not even trying to start. The dash doesn't dim and there's no relay clicking, so I don't think you're getting power to the starter. Check fuses, and then maybe starter relay. Bad timing, but 20 year old starters do die...
You could also check the clutch safety switch on the clutch pedal, make sure it's not stuck and still connected.

Regarding the lights, oh boy. Coolant light constant on is the level sensor in the coolant bottle failing. Not uncommon, solution is a new bottle, but there's a 95% chance you'll break the radiator nipple it attaches to, so might want to plan on rad replacement at the same time.

Check engine light: need to know what codes it's throwing.

Headlight level light: not uncommon, the level sensor on the left side suspension can corrode and die. Can be cleaned out or replaced.

Traction control always on: check codes. Failing wheel speed sensor or some communication problem might be in play.

I wonder if you have CANBUS issues and there's not reliable communication between the key cylinder, ECU, ABS, etc. Those will show up as OBD codes.

Adonnis248

Last time I tried to hook up to a reader it wouldn’t connect regardless of car on or off. And start would be probably the easiest of all problems you described. I will be pulling plugs and coils probably today and cleaning them and will check the clutch switch as well. I greatly appreciate your help. I will keep you informed as I go what I find.

Adonnis248

Canbus??? Where is this hose supposed to go from the oil cap by chance and this is what I am working with right now

Loki

iTrader: (1)

Ah a hot air intake. Yeah you're gonna want to go back to stock, those things cause all kinds of headaches.

That hose should plug into the intake. You can google "rx8 vacuum diagram". No hoses should be open, loose or cracked, they will throw off air intake measurement.

Is your battery not tied down at all? Yikes. Maybe raid a junkyard for all the underhood plastics including the intake.

Adonnis248

I will be looking that up shortly. Hopefully an easy fix. Probably have to buy new hose. And they seem hard to find in the scrape yards. Seem like they get totaled and crushed or are kept in garages. I was just at the dream cruise in Detroit and didn’t see one rx8 or 7 that I can think of.

Adonnis248

Pulled starter had it tested at two different places. Passed both. Fuses are good. And still not turning over. Not sure how to do the compression test and can’t find where the oil intake hose is supposed to go. Nothing I can find properly shows the receiving end of where it mates up at.

Loki

iTrader: (1)

The diagram in thos thread shows where to connect the loose hose. Ignore the catch can drawn in there. This assumes a stock intake, totally possible whatever intake that is doesn't have enough nipples.

https://www.rx8club.com/series-i-tec...iagram-214910/

Hmm. Is the starter relay OK? And the immobilizer light (car with key in it) isn't on?

200.mph

iTrader: (9)

it needs to run/crank before you can do a compression test.

as stated the hose from the oil fill is supposed to go to the intake

Adonnis248

So got it running. The blonde in me was going hard because I apparently used the wrong fob. So that leaves me wondering. How did they by pass the intake line because it is driving again and I never hooked the line up. Can I plug that line since it has been bypassed even though I haven’t found how yet.

200.mph

iTrader: (9)

the line coming off the oil fill neck? i re routed mine to a vented catch can and put a vaccumm cap on the intake nipple it went to. i suppose you can just cap both ends

Loki

iTrader: (1)

The reason that line exists is to vent the oil pan. It can be open to atmosphere but it will mist oil everywhere and the vapours are highly carcinogenic, so you probably don't want that. Since your intake doesn't appear to have a nipple for this line, it's still air tight so the car runs... But that's another reason among many to garbage that intake.

Adonnis248

The under side is definitely coated with oil which I really don’t mind because the bolts break easier underneath them but could it also have something to do with compression. Reason I ask is fifth and sixth gear at six to seven and a half ton the motor disappears. And what would I look up for catch pan or bottle for that. I’d rather keep it sealed off with a return line back to oil cap

Loki

iTrader: (1)

Well.. if you route the crankcase vent to the oil cap, you're not really venting anything and crankcase pressure will find its way out somewhere else... oil pan, main seals, etc. Do not do this. You can tee one of the existing intake nipples if you really insist on keeping it, but the correct answer here is getting the correct intake for the car.

As for the engine dropping out, is it only in 5th/6th? Also what are you doing at 7k in 6th? That's the car's aerodynamic limit ~155mph. It will never really accelerate past that. What happens in more reasonable gears?

Adonnis248

I was seven k at 117 playing around with a mustang leaving frankenmuth me back to the bricks event in Michigan and it just went out for a split second. And then back and struggled to get past that. That’s when the engine light blinks at me. The power is down. I know that. Hoping to do a compression test in the next week or so. And replace coils as well as everything else to do with spark.

200.mph

iTrader: (9)

a flashing cel is usually a misfire and is usually ignition related

Adonnis248

That would make sense then so I need to redo the coils plugs and wires then. Should I also redo the internals as far as seals and stuff as well??