Hi All,

Got a 8 50,000 km, automatic 2004. until recently the car was running really smooth and about 2 weeks ago discoverd a engine cut off problem at 5000 rpm after a long drive. eventually the engine will stop by it self and would not start for about 10 mins. after things cool down engine starts back and runs fine. no engine light come on or difference in pulling power. if driving below 5000 rpm problem will not occur. what seems to be the problem . need some advice guys?

 

Sounds like coils are getting overheated. I would pick new ones. How are hot starts if engine is at operating temp and you shut it off and start in about 30 seconds. If it takes longer then 5 seconds to start you have a failing engine. If these are ok check your fuel pump. When it overheats (due to it failing slowly) It will shut off. Thus no fuel and engine dies until pump cools down (10 min) and it starts right up.

 

Get a compression test. It's the engine or the fuel pump, but there is no point in fixing the fuel pump if you need a new engine.

 

Sorry for jumping in this thread, cant make a topic yet (new account)

So i got an RX8 willing to throw money in it long term (even rebuild the engine if needed)
2004 RX8 with 95k miles. AT

The car was sitting in storage for maybe a few months before I got my hands on it. So here are the issues:

Day 1: The first time starting it out of storage, it was having a hard time. Eventually it got running but it does not have normal start up procedures (normally the engine should rev around 1.5k-2k RPMs to heat up to operating temp?) the RPMs were hunting hard between 500-1000. had a very rough idle, and stalls after a few seconds. the CEL is on with codes P0107, P2259, and P0031.

Day 2: I changed the starter, coils, plugs and wires. Also went ahead and gave it a fresh oil change. I also cleaned the MAF and Throttle Body. The cold start is still a bit rough, but better. It will still stall if I don't feather the gas. The engine will also hesitate at low RPMs (800-1500) but once it reaches around 2k, its able to rev pretty freely (but slowly) up to 5k (hard cap?) at this point I was thinking that the car was in limp mode.

Day 3: Cold started the car and to my surprise it seemed to start perfectly fine, almost felt normal. The engine revved up to 2k RPMs immediately, and as the car began to warm up it slowly dropped to a 800-1k smooth idle. The car seems completely fine but will still not rev passed 5k RPMs. After a few more minutes, the car will begin to idle rough again and eventually stall. I can feather the gas to keep it alive. Revving the engine will hesitate between 800-1.5k rpms, but again be consistent from 1.5k-5k (wont rev passed 5k still)

I turn the car off here, and decide to wait a few seconds and do a hot start. It had a hard time starting up (5-6 seconds?) and immediately started idling roughly again/stalling.

Is the car in limp mode? from searching im thinking the engine may have very low compression since the ignition system is in working order.

The weird thing is though: if i start the car (hot or cold) i can rev the engine up to redline easily if i rev the car within a few seconds of starting it. Then eventually after a few seconds it will drop to the 5k cap even if im flooring it.

I also found a receipt for gas that the previous owner had in the back of the car, the last fill up was with regular gas, i've heard this can cause issues.

So right now im thinking:
Low Engine Compression
Bad Front O2 Sensor? (P0031)
Bad Air Solenoid? (P2259)
Bad BARO Sensor? (P0107)
Bad Cat? The cat looks really rusty/worn.

I was also thinking it could be the fuel pump/fuel injector? I've read that once these get hot it can causes this type of issue as well.

Also would low compression keep me from passing 5k rpms? isnt compression supposed to improve with higher RPM. The engine is not misfiring at all, also sounds fine. I dont think an apex seal is blown since it starts/idles completely fine cold, is this right? Im very sure the seals have worn down, and the compression isnt what it should be, naturally, but would that cause my described issue?

I'm going to get the compression checked, but I wanted to see if there was an obvious issue that would directly cause this problem

 

You can make a topic in the new members section.
Get a compression test for sure. It's not limp mode, that kicks in around 3000rpm.
You're on the right track.

Front O2 or the wiring to it are damaged (P0031)
The air pump doesn't matter, so don't worry about it for now (P2259)
P0107 BARO or wiring to it are damaged.

Did a critter try to eat your wiring harness and cause these electrical issues?

Again please make your own thread in the new members section.

 

i made my own topic here: https://www.rx8club.com/new-member-f...3/#post4921806

if you guys have any ideas that would be very helpful