If I'm going to do this compression test do I need to take out all of the spark plugs and the fuse or just certain spark plugs?

The CAS tested okay using the resistance test on the plug. We adjusted the CAS (which was very hard to do, had to use a crowbar) but we weren't sure where to make the adjustment because there was no mark on the pulley. We couldn't tell little rust spots from markings. There sure wasn't any clear markings.

If I get the CAS where it needs to be then would adjusting the TPS help my problem?

 

Compression test should be done with one spark plug from the rotor you are testing removed. Then repeat with the other rotor. In all you should have removed 2 spark plugs, one per test, replacing the other when you test the next rotor.

CAS + TPS adjustment may help. I had a motor with similar problems and it was the CAS. BUT I've also had problems like the rest of what you describe (no power, etc) and turned out I needed a rebuild - my seals tossed on me.

So definitely check your compression, and definitely check your timing. That mark on the pulley can be a major bitch to find, but its there. Make sure your CAS is in good working order too... do a search and you'll see various tests for it (here and maybe try google too). Get a copy of the FSM from the various places online so you can read some Mazda troubleshooting tips as well -- good stuff there for sure.

Good luck. Once these things start to run like bitches its usually time for some major "fun" ....

 

For the compression test does it matter which plug to remove? Trailing or leading? Either one?

 

I don't think it matters for the simple ear test, no. But if you want to be on the safe side pull the leading plugs. They are at the point of max compression. Although when I did it myself I used the trailing and it was loud enough to hear from the driver's seat.

 

I have yet to understand why, after numerous recommendations, people refuse to do a simple 2 minute compression procedure that will tell them whether or not there is ANY use of pursuing further troubleshooting.

People would rather ask and ask and ask questions, spend a day and a half checking specs in the service manual, or even perform an indian rain dance ritual around their car rather than remove a couple of sparkplugs.



BTW, it does sound like a blow apex seal or 3. They USUALLY give out while driving, with NO WARNING. This results in 3 whooshes and good compression on one of the rotors, and nada on the other. Sometimes you see a motor that still has 2 seals semi-intact and makes compression on one face of the 3, but it doesn't matter, it still has to come out and apart.

 

I've asked these questions to understand my car better and because all of the things I've asked about I haven't come across yet or done maitenance for, which is why I asked about them. I haven't before done anything with timing, the CAS, AFM, etc. Timing was something I wanted to do anyway because it didn't seem right to me the way it was. Of course I'm hesitant to check the compression, it's just a confirmation of the fact that I would have to spend almost what I paid for the car just to get a working engine again. I'm not even done paying off the car itself yet. That and I wasn't sure how to check compression Now that I do however I'm going to go check it.

 

Rugged rotary, have you done the check on yours yet?

According to the compression test on my car there were 3 good, strong, rapid 'wooshes' on the front housing and on the rear they were weak and spread out. I guess it's safe to say then that my rear rotor has no compression.

 

Anyone know if Banzai Racing does engine rebuilds? They're only about 45 minutes away from where I live. Anyone with past experiences with them I'd like to hear from.

 

Yo, trust me. Kevin (RotaryResurrection) is the man for a rebuild. He knows his stuff, to a T, has experience with every single mazda engine, flavor, and combination, and did my TII rebuild to boot. He does good work, has a great reputation, is a nice guy, and is genuinely concerned about people's issues with these engines. He might seem "curt" at first but that's because truly he's seen so many people ask questions and do NOTHING but keep asking questions, that he has to see some initiative. But I would not send my engines to too many people. There are a few who have good names for racing engines (BDC, Ito, Pineapple is struggling now with their rep but they've had a very good one for a long time -- any of these seem to have very devoted and loyal followers too) but very very few who are consistently reliable, priced well, and super knowledgable when it comes to building a solid, clean, daily driver engine. And Kevin is your man. Trust me, the shipping is worth it. But remember, don't bug the death out of the guy about every little thing - he's a pro, not a "shop". He does it to help the community, to make a few bucks, and mostly I think because he just enjoys the rotary engine and can make a decent living off of working with it. You can't get more straight up than that.

And Kev... killer quote in the sig. Amen, and amen.

 

Hey you haven't been online lately. I was talking to some of the guys at the Fort Wayne DSM Club meeting and was talking abou thow you couldn't find any local places that know anything about rotaries. They mentioned that HSU Tuning place down the street on Lima, you should call em up Monday.

-Donovan

P.S. I'll drive you to classes for $4.99/class

 

definetly sounds like you got a dead rotor- now you gotta figure out WHY it's dead...you've changed the plugs, and verified ignition (that T2 wire gets funky on me, too, at idle)...I know from experience that if you have a primary injector crap out on you you'll get the same symptoms you're describing- having to keep your foot on the peddle to keep it idling, backfiring, etc...I know there's not much room to maneuver down there, but try to get something (screwdriver?) down on the primary injectors and listen for the clicking that should be going on..if you just changed the fuel filter, maybe something got dislodged and clogged up that injector (which also has it's own little filter screen). I finally "fixed" mine by swapping the secondary injectors into the primary positions...you can also troubleshoot from the ECU to see if the electrical signals are being sent to the injectors if you think it might be electrical- look for the voltage dropping as the RPM's increase. Be careful of the old brittle fuel lines & such if you're gonna dig down to the primaries to swap 'em! Good luck

 

So you're saying it might've been another factor outside of mileage (118k) and age that caused the rotor to fail? Basically if something else was wrong and I got a rebuild it would be at risk of happening again/sooner than it should?

 

all I'm saying is I would make sure everything is working as it should before giving up and replacing the engine...I've got 182,000 on my n/a and several times I thought I blew the engine when it was something else entirely causing the probs...learn how to troubleshoot- even to the point of going page-by-page in the Haynes or FSM- everything you learn will be used when you run into problems in the future. Have you even done the compression check yet?

 

Yes, I did the compression check. It's in the thread a little bit back in response to rugged rotary.

 

 

Ah my bad forum lagging badly here.... carry on mates.

Yeah losing a rear rotor is apparently typical on S5's, I believe I lost my rear rotor as well. S4's I think toss the front one more often IIRC. And glad to hear you did the check... you're one step closer to the dark side... *ahem* I mean doing stuff yourself.

 

oh, O.K. man, sorry, speed-read right on past that point, so you got little or no compression rear rotor...in that case, forget about the primary injector scenario!

 

Dang, giving me false hopes and such

 

I gotta redo my compression test cause i did it wrong i took out all the plugs and took out the egi fuse and heard pop after pop after pop so iam going to do it one more time and take out the leading plugs and try it.