So my 2004 GT (6 port) with 109k on the original engine broke down the other morning. Was driving along with no issues, when all of a sudden the engine started "bogging down" like it had some bad fuel, or some trash in the fuel. I pulled over where it sputtered out and died. I tried starting it back up, but had no luck. It would crank and crank, but no start... Luckily, it was off the road and in a parking spot at a local drug store.


I ended up calling a friend for a ride, and left my car there for a few hours. When my next door neighbor got home, we rode back up to where my car was with the intention of towing it back to my house, but I decided to jump in it and see of it would start... and it DID! But only running like crap. (My analogy of how bad it was running, was that if it were a V8, it was like it was running on only 1 cylinder!) Had the power of a kitten... But since we were only about a block away from my house, I decided to putt putt the thing down the road barley running just to get it to the house.


I kept thinking along the way that this was probably a bad idea, and that I was likely doing more damage to the engine trying to run it this way, but I made it to my driveway at my house, and there it died as soon as I took my foot off of the gas... never to start up again.


So here it sits, 109k miles and broken down. About a year and a half ago, (about 20k miles ago) it did the same thing, and broke down the same way, with the same symptoms... where I incorrectly diagnosed it as a bad fuel pump. So after buying and installing the fuel pump, it wasn't until I replaced the spark plugs, wires, and coil packs, that I managed to get her running again. And it's been running great ever since, that is, up until the other morning.


So what do you guys think; should I do the right thing, and have it towed to the dealer and have a compression test done, and see if the engine has enough life left in it to be worth fixing? Or should I gamble, and buy some spark plugs, wires, and coil packs and hope that's the fix?


BTW, does the car have to be running to have the compression test done? And is this compression test like normal compression tests that regular piston engine mechanics can do, or do I need to have a rotary specialist do the test?


Thanks in advance for any input on the matter!


Ed

 

^ Yes, proper next step is a rotary-specific compression test. (And yes, this is not the same as the ordinary compression test most any mechanic can perform.)

 

Read the new and potential owners thread while your car is getting its compression checked. You'll gain a better understanding of this engine, and where potential faults lie. You could be experiencing a simple issue, to catastrophic failure, and it will assist you in the future to diagnose your issues

 

Thanks, that's what I thought. I guess I'll have to call my local dealer and see how much it'll cost me to have it towed there and have the test done.

 

Thank you. I've read all that. (Notice my join date) I've had this car for a couple years and have found this forum to be indispensable. I've fixed things before with the help of members here and their expansive knowledge of this particular engine.

My post here was basically looking for confirmation, that it is indeed time to have the compression test done. I really didn't have to ask, (more or less just thinking out loud here, and wanting to document what is happening with the car) I knew by reading all of those "new owner" threads that a first gen ('04) RX8 with over 100k on the original engine is going to need some attention soon.

Once the test is out of the way, then I'll know how to proceed. If it comes back good, I'll go with what I know (and what I've learned here) and look at the ignition system. (New plugs, wires, and coils (again)).

If the compression test fails though, and I need a new engine, I'll probably have to push the car into my garage and park it until after the first of the year. No worries.. it'll just have to wait.

 

How would they do the compression test if his engine won't start? I'm probably missing something, but don't they have to get the rotors spinning to test compression?

 

To do a compression test (on any combustion engine) it only has to crank to test compression.

 

At that mileage a compression test is a good idea rather than paying for parts you may not need.

But, make sure you get printed results, if the dealer is doing it right then they will hook it up to the WDS system and print results. You are paying for a by the book test from Mazda so make sure you get one because some dealers are lazy and try to give customers verbal results or hand written and that means the test was not done right. The engine should be warm when the test is done so hopefully they can get it running for a bit. But compression also may be so bad that it won't run and if that is the case then it doesn't matter if the engine is warm.

 

Right. That's what I thought. I remembered way back when, when I had one done on an old Chrysler I had, one spark plug at a time had to come out for the gauges to be connected, and we cranked the engine by hand (with a big wrench on the crank bolt) to get the compression readings. The engine was obviously not running with plugs being removed.

I just wasn't sure if these rotaries had some different method. I do understand that the gauges are different though.

 

Thank you. I'll make sure to get printed results, and when I get around to getting it done, I'll share them here.

I can tell you when I turn the key and crank it now, it sure seems like there's no compression. It just cranks and seems like it's just spinning freely... I'm pretty sure it's time for an engine.

Which has me thinking; if I do in fact need a new engine, is it worth it for this almost 13 year old car. The car otherwise still needs a paint job (bad!), it's going to need tires soon, brakes, and not to mention the radio/AC control unit has completely stopped working. (Well, the AC works, but the display has gone kaput)...

I guess I need to decide how much I really love the car. It IS (was) fun to drive! But for the kind of money I'll have to put into it to get it back on the road, I could get something else that's really nice. I figure the engine, even if I bought it and had it shipped to my house, and installed it myself (which I am capable of doing), would cost me around 3 grand for everything (am I right?), then another couple thousand on a paint job, and fixing everything else. I could get a real nice used car for 5 grand! Shoot, I could probably find a real nice, later model year RX8 with low mileage for that price...

Hmmm... I guess it's a good thing I'm not in a hurry. I'll think about it for a while. In the meantime, I have my GF's Civic to get around in. No worries!

Thanks for all the feedback and input guys!

 

I had a similiar problem with mine a couple of times. The first time it happened it turned out to be my cat, it was so plugged up , it was glowing cherry red from just warming up. I have a racing beat exhaust system so i heard the difference right away. Car was driving fine before that with no signs or codes. When i had a coil bad, my check engine light was reading missifres as well. The second time it was acting like u described was when i had my clutch was replaced at the dealership and they didnt properly fit my intake back in place. The filter was detatched from the maf sensor. I would check to make sure, rx8's are sensative when it comes to air intakes.

 

Thanks for the input. I've had my intake on and off several times, just the other day in fact, while I was checking my coil connections. I know it's not that. I think even with the intake/air filter box removed from the car, the engine would still start.

 

(Of course, if it turns out your 8 needs a new engine AND a new paint job, new radio and lots of other little things, it might well make more sense to sell yours for whatever small amount you can get and BUY a better used one. Never much in demand, used 8's are available at great prices.)