airman3221

Hey guys! I'll cut to the chase. I got scammed by the previous owner since the compression test I got was rigged by him. The car has 61k miles on it.

How many more miles do you guys think my rx8 could last? Also, should I rebuild it now or should I do it later/when it blows up?

Here's the compression test results:
Rotor 1 at 290 rpm : 5.6---6.0---5.7
​​​​​​​Rotor 2 at 291 rpm : 5.9---5.7---5.7One more thing to add, except from the PCM issue I'm facing (you can look at my other threads), when the PCM does work properly, the car starts perfectly fine, no smokes coming out of my exhaust and there's no weird/unusual sounds coming from my engine.



Thanks!

dannobre

iTrader: (3)

I didn't read the other threads... but usually a PCM issue isn't intermittent. A sensor may be, or fuel delivery etc... but PCM's are like computers they usually work... or don't.

You also might have a ground or connection issue at the PCM. Thats easy to check...

Not going to lie...The compression numbers aren't great...

Once the compression gets really low you start gettting blow by and that makes things deteriorate quicker and can result in failure of a seal... that can take out large parts that usually can be reused... so don't wait for it to fail before you do something

airman3221

Thanks for the reply!

My guess is that it's also a bad grounding issue (hopefully). I'm gonna take a look in a few weeks once I get some time off from work.

Yes, I agree the compression numbers really aren't great. The place where I went to do a pre-purchase inspection, the previous owner knew the guy, so all the results I got back was rigged. And then one by one I got surprises.

I'm highly considering selling the car because I don't think it would be worth rebuilding it. I didn't even get a few days to get attached to the car.

Anyways, what do you guys think I should do?

BigCajun

iTrader: (1)

Is this your primary vehicle?
If not be patient, if so, that's a harder decision.

I paid a LOT for my low mileage '04 in '12.
4 days after I bought it the CEL came on for a bad cat, 8 days out of warranty.

I was quoted $1700 for a new cat, I was tapped out, but it ran fine so I stupidly kept driving it.

I knew about rotaries, but didn't realize the Renesis was so different.
The more I read on the internet, the more discouraged I got thinking I bought a lemon and was screwed, so I know how you feel.

I had a truck but I enjoyed driving the 8 and except for the occasional misfire and CEL I kept driving it.
First winter I had health issues and parked it for a few months.
That's when I joined the forum and started really learning.
A lot of guys here really helped me out and gave me encouragement so I want to do the same.

In hindsight the most important thing I learned was misfires kill cats, bad cats kill engines.

I Installed a BHR midpipe, new coils and plugs learned how to clean ESS and MAF sensor, and replaced the weak battery.

Started driving it again, fell in love with it and it was so dependable it was my DD for 8 more years and 80k miles except for snow days.

In my case I didn't find out my engine was failing until when, just out of curiosity, I had it checked when I had the airbag recall addressed.
I was shocked.
I think I damaged it driving it for months with a bad cat at the beginning.

I got a couple of more years out of it before it failed completely.
It sat for 3 years.

I just sunk likely way more money than the car is worth to drop a new engine in it and address a bunch of 100k mile issues because I love the car so much.
I'll be getting it back soon and I am super excited.

I bought another '04 to DD after my old truck rusted out but it only lasted a couple of years before it started dying, just bought it off a guy because it was convenient.

Traded it in this year on my Frontier for $1500.

Don't get too discouraged yet.

A lot of common RX8 problems are easy fixes, and many will run a LONG time with bad compression numbers.

airman3221

Hey thanks for the reply!

After thinking about it for awhile, I'm still confused on whether I should sell it or no. The whole scam thing really discouraged me a lot and now there's stuff breaking left and right. Fortunately, I have a Celica that I use as a daily, so I can pause whatever I'm doing on my rx8. But on the other hand, I only got to drive it 4 times since I owned it and it's been only giving me more susrpsises including the low compression. Because of this, I don't have much attachment to it,

Anyways, winter is coming so I'm planning to tackle all the electrical problem on it. If that goes well, then next step will be to either rebuild the engine or put in a new one. Only experience on cars I got is changing oil, so I don't know if I'll be able to pull it off.

Otherwise, I'll just sell this. If I do, I hope I get a good amount of money.

Thanks for trying to cheer me up man, but I think my car is close to the point of an actual shitbox

Let's see how it goes...

Chrishoky

iTrader: (9)

Unlikely if you are honest with the future buyer about the compression issues. Unfortunately RX8's with low compression aren't worth much beyond shell price. You don't want to be a 'scammer' to the next person, so be honest. Even if they aren't familiar with RX8's.

BigCajun

iTrader: (1)

What kind of electrical issues?

As far as I know, new engines aren't available anymore.
I was told I bought the last new engine in the U.S.

It doesn't mean there won't be anymore as I did see a story from Mazda that they are still making new Renesis engines.

I paid $6k for the still crated engine, $800 for a rotary expert to drop it in my 8.
Usually $1200, but got a discount for letting him keep the original engine for parts.

airman3221

Thanks for the reply guys!

For electrical issues, I'm still working on finding what it is, but long story short:

1- the connecter that connects the PCM with all the other module (Keyless unit, dash, immobilizer, etc) works intermittently. When it doesn't work, all those module start to give out codes saying that there's a connection error with the PCM

2- Flashers system only work when the car is cold. I tried replacing the relay/flasher control module, but nothing happened.

For the engine, I'm heavily considering rebuilding it myself. While I don't have any experience on cars, I do overhaul small aircraft engines (lycomings and continental). So this slightly boosts my confidence.

Once again, I'm not sure if I should try to rebuild it myself or just sell it.

Edit: Just something I forgot to add. Of course, I hate the idea of scamming people, so if I do end up selling it, I'll tell everything the next owner needs to know about the car so he doesn't find any surprises like I got.

schm1347

I’d personally get the engine rebuilt by a reputable rebuilder. Plenty of people can help you out with that on this forum. Rotary engines are simple in conceit but there is a fair amount of know how to properly rebuild an engine - specifically knowing what you can and can’t reuse. People often make the mistake of reusing out of spec parts and getting very short life out of rebuild.

For a few more thousand (long sigh because you just paid for the car) you can get a rebuilt engine that should give you several tens of thousands of miles of enjoyment if not more provided you keep the engine fresh on oil, ignition systems in good health, and the catalytic converter from clogging.

But you might be able to run the current engine a long time. Who knows…it’s a crapshoot. Since it’s not your primary car, if I was in your shoes I would drive it as long as it starts. If you don’t have any hot start issues or misfires the low compression while existent isn’t going to affect your enjoyment of the car. Regardless save your money. If you fall in love with the car you can put that towards a new engine. If you don’t then you have money for something else.

BigCajun

iTrader: (1)

I'll repeat, don't DIY a rebuild.
If your engine runs fine with no hot start issues, you should concentrate on fixing the other problems first.
If you try to rebuild it if it's running good you could wind up with worse numbers than you have now.
It's not as easy as it seems.

Electrical issues are my Achilles Heel.
I'm no good at it.
Unless you are experienced at fixing electrical problems you could bring it to a reputable local mechanic shop to troubleshoot it for you.
RX8s have their idiosyncratic issues, but electrical, suspension, etc. are like most other cars and most good shops should be able to sort it out.
I recently paid a trusted shop $300 to repair a whole bunch of squirrel chewed wires in my WB before I traded it in.

If you sell it disclosing the low compression numbers, I don't think you'll get more than a few thousand unless it's in pristine shape.

Be patient.

You are relying on OBD codes for troubleshooting?

Here is another way to troubleshoot some electrical issues.
The Immobilizer section was helpful in tracking down a short I had once.

https://www.rx8club.com/series-i-do-...utputs-155947/

schm1347

^+1 for don’t rebuild yourself. If it hot starts fine, just fix everything else and drive it. In that case the engine is not your biggest near term concern.

airman3221

There's no issue starting up hot and cold (when the electrical issue is gone for awhile). There's also no weird unusual smoke coming out of the exhaust and no unusual sounds.

After thinking about it, I decided that I'll listen to you guys and drive it til it really needs a rebuild. It might die the next time I drive or may last me awhile, who knows? Hopefully it's long enough for me to save up money for a proper rebuild.

On the DIY rebuild topic, I am very very curious on how it's done. That's why I might end up getting a Reman engine for the car and rebuilding the current engine myself. If I mess up, then I still have time to recover with the reman engine.

Thanks for the tip guys! I'm always open for more if someone wants to add something!

BigCajun

iTrader: (1)

Do your research before sourcing a reman.
There are some hit and miss out there, and remember the old adage, "If it sounds too good to be true..."

If you really want to rebuild a Renesis, maybe you could source a bad engine from a salvage yard and attempt tearing it down and putting it back together.
Parts kits are not cheap, so you need to be as prepared and knowledgeable as possible so as not to waste hundreds, if not thousands of $$.

Talking to the pro rebuilder who is working on my LY atm, he doesn't recommend aftermarket seals like Atkins.
He was showing me a rebuilt engine he had just finished.

I do have a good IC mechanical background, but I've no experience tearing down rotaries.
There may be some advantage to practicing a tear down and reassembly just for practical knowledge of the tools and equipment needed before attempting a serious rebuild.

Read the rebuilders thread and the threads linked in it.
There is a lot of good info in there, especially the one from Kevin at Rotary Resurrection who breaks down expectations of customers and the practical realities of their budget on results.

https://www.rx8club.com/series-i-tec...ilders-265177/

airman3221

I thought that reman engine would be the "safest option" since it comes from Mazda and it's the most expensive option, but I guess I'm wrong haha.

I contacted the rebuild shop in Calgary, (https://www.rotaryengine.com/) and they told me that my compression is still pretty high to rebuild. I did get a quote on how much it will cost and I'll start saving up for it.

I will take your suggestion to get a broken 8 engine and rebuild it myself since it looks pretty interesting.

Anyways, thanks again for the tips. And once again, I'm always open for more suggestions!

Loki

iTrader: (1)

Getting a junk yard engine isn't a great idea. It's in the junkyard for a reason, and the risk is big parts (housings) are worn out and can't be reused. Rebuilding a rotary isn't just replacing the seals, you need everything to be in spec.

Mazda rebuilds these days should be safe, or at least come with a warranty. For a time Mazda was producing new engines again for some reason, not sure if that's still happening.

BigCajun

iTrader: (1)

I was suggesting that as an experimental practice rebuild, tear down and assembly only, not a functional rebuild.
I discouraged him from a DIY rebuild.

airman3221

Like you said, the broken engine will just be to tear it down, see how everything should normally get inspected and put everything back together. This would help me make all the mistakes during a proper rebuild now instead of doing it on my current engine for the first time. Of course, I won't put this in my car since I'm sure it's going to be out of tolerence

schm1347

I could be wrong about this but I would think if you play with a rebuild you would want to hook a starter up so you can at least hear it crank and test the compression while it’s cranking. If the engine isn’t rebuilt properly it either won’t crank at all or will have low compression.

I would think you should be able to do this without having to go through the work of putting in a car first :D. With the engine out you can take apart and rebuild it a few times to get the compression right.

airman3221

If this is a way to check the compression, then you are a very smart man! Thanks for the tip!

Loki

iTrader: (1)

I mean you'll need to give it some oil if you want to spin it up to 250rpm for a proper reading. I'm not sold on this being practical, but you do you.

airman3221

Of course, I will do more research on this and how to properly do it. If done properly, then it might save lots of money and time haha