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2005 Mazda Rx8 knock at idle with revs. 60,000 miles car had new motor put in, in 2013. I have changed plugs, wires, coils. Smokes light blue. I have beat cat out, and checked And cleaned SSV. Cleaned ESS. reset ESS (20brakepedaldance) and pulled room fuse. Smells like someone has dumped Lucas motor treatment or something in the oil. Will idle as long as you let it. Will not start after warmed up. I would appreciate any help or advice. I have searched all the forums and googled myself crazy. Thank you for your time. I’m going to do a compression test soon. Here’s two videos I recorded
Can isolate what is knocking? If you take a piece of wood and put one end to your ear and the other on individual parts you will hear very clearly through the stick when you touch the part that is actually knocking. If it's the engine block, stick a fork in it. It's possible it's one of the intake valves. Try to narrow it down.
But also what is that engine bay smoke in the 2nd video? Do you have an open vacuum hose somewhere?
The no start when warmed up condition is likely compression, get that test done. If it's no good, being an automatic, you may want to consider if it's worth saving. The automatic engines, especially 2004-2005 are weaker, more expensive to replace and more problematic models.
thank you for the response Loki. I’ll try that using a piece of wood and listening. It sounds low in sound, but sound moves even from when laying underneath. but only movement I can feel is in the intake plenum rattling a bit when holding it and it running. How would I know if it’s one of the intake valves? It’s smoking because I broke the nipple off the radiator and was spraying water into the cooling system to keep it cold while I’m trying to diagnose this problem. But light blue smoke out of the exhaust. A vacuum or solenoid wouldn’t cause this knocking would it? And that’s unfortunate if this motor is toast. I’ll do the test ASAP. I have been looking for a motor in the worst case situation and yes you’re right. They are not cheap.. fml. Lol thanks again brother. If anyone else has any ideas or thoughts or have heard this noise I’d really appreciate it.
Last edited by LionO; 11-05-2017 at 07:49 PM.
Reason: Asking more people to chime in.
Haha ok. So there’s bearings in the intake housing where the VDI and SSV are? Could this noise be that? Or just pull whole intake and look at the two that go down into block? I know those move pretty freely when pulled out. So I guess the question is what would I be looking for? So many questions I know. This engine was made by aliens, and martians lol . Sitting here playing forza horizon 3 in a RX8 and hearing no knocking. Strange. Lol
So here’s an update.. today finally found time to mess with her. I thought I’d give the seafoam through the nipples on the intake a try. Pulled ESS pigtail off. Cranked it ( with my remote start someone put on the car) and sprayed seafoam in the nipples. Did that back and forth on each nipple till can was empty. Let it soak for an hour and then started it up. Knock was still there and smoking like crazy which I exspected. I started revving it and it seemed like the knock was slowly going away so I went to try and red line. And it wouldn’t get to red line. And started misfiring close to redline. I let off the gas and it died. Got out and under the hood oil was every where and my dipstick was up out of the hole. Smelled like hot Lucas or marine oil. Tried starting it for another hour and will not start. I was going to do a compression test after I seafoamed idk if that’s even necessary at this point. Idk if a rear man bearing would cause this knock or if the apex seals would. Should I still compression test it tomorrow? Frustrated but trying to learn what it could be. Thanks for anyone who’s listening.
If there is enough crankcase pressure to pop the dipstick and spray out oil, the knock doesn't super matter. She's dead, Jim. You've lost a side seal somewhere.
damnit Jim I’m a scientist not a doctor! Haha and yeah for sure man. Somethings not there. Thank you for your replies means a lot. I started tearing into it today. Slowly going to get the motor up and out. I’m going to take it apart and look and see what happened exactly. Starting to look for another 13B to put in. If you have any suggestions I’d appreciate it. As much as I’d love to LS swap it, its a lot of work. And It’s starting to be winter. And no garage means cold and dark. I love the sound of these motors and maybe could learn a lot more about them and stick to rotarys. And just rebuild them when they fail. So the quickest fix I’d think is to buy another motor and rebuild this one if it’s not complete junk. Thanks again man
I’m a scientist not a doctor Jim! Haha thanks for the reply. I really appreciate it. You’re right somethings not right.. so I started on the pulling out the motor process today. I’m starting to look for another motor if you have any suggestions I’d appreciate it. So that way I could possibly rebuild this one if it’s not complete junk while driving on another motor. I was even thinking on doing a LS swap but with the fabrication required, and with winter hours and winter time coming. Without a garage means cold and dark. So I’m going to stick to the 13B for now. Who knows I might learn them and actually stick with them. I appreciate a
ll your help and replies.
Last edited by LionO; 11-12-2017 at 07:05 PM.
Reason: Added picture
Get in touch with Rotary Resurrection (he's here on the forum, for example). Rebuilding the engine you haven't isn't the best approach, since big expensive parts may be out of spec. Usually you want to buy a rebuilt one from someone who knows what they're doing. Often, rebuilders will take your engine for parts and credit you some of the cost of your rebuilt engine.
Other options: Pettit Racing, Pineapple Racing... Mazda
I can actually agree with that. Id hate to put money into something. And not knowing what certain tolerances that could put a part out of commission. Then id be back to square one after putting time and money into it. I'd rather have mine rebuilt or buy a rebuilt one. I'd hate to buy a used one from a junk yard and then it go out. Then i'd be upset I didn't put the money into a rebuilt one. I'll look into those and get in contact with one. I'm not looking for a race build or anything. Something to cruise with and maybe even make it my DD. The LS idea I had wasn't for power but for reliability. I'm just nervous about how you can send you're motor in for a rebuild and have a budget in mind and then they call and say its worse than expected. I just hope in my case its nothing major. Is it worth investigating before calling/emailing rebuild shops so that way i know im safe on parts that failed? Thanks again brother.
Yes Loki. I’ll look into those. I’d hate to rebuilt it myself and not knowing the tolences of a failed part. Have money and time invested in it and it fail again. That would be frustrating. The idea I had on the LS swap was for more reliability, not for power. I’m not looking for a race engine or anything but I understand only a racing shop will be doing rebuilds. I hate the idea of buying a used motor from a junk yard and it fail prematurely and I’d be back to square one. The scary thing to me is sending it off to one of the rebuild shops with a budget in mind, and getting a call saying it’s way worse than expected. I’d really hope it’s nothing major in my case. Is it worth investigating and looking to see what failed to be on the safe side? Just so that way before calling/emailing shops I have a general idea. Thanks again Loki. And gwilliams thanks for those suggestions I’ll look into those as well
Yes Loki. I’ll look into those. I’d hate to rebuilt it myself and not knowing the tolences of a failed part. Have money and time invested in it and it fail again. That would be frustrating. The idea I had on the LS swap was for more reliability, not for power. I’m not looking for a race engine or anything but I understand only a racing shop will be doing rebuilds. I hate the idea of buying a used motor from a junk yard and it fail prematurely and I’d be back to square one. The scary thing to me is sending it off to one of the rebuild shops with a budget in mind, and getting a call saying it’s way worse than expected. I’d really hope it’s nothing major in my case. Is it worth investigating and looking to see what failed to be on the safe side? Just so that way before calling/emailing shops I have a general idea. Thanks again Loki. And gwilliams thanks for those suggestions I’ll look into those as well.
Quick update. No metal shavings in oil. Or oil filter. So far I have found three things of interest. And would love someone to shed some light on the situation. I’m still being the motor out just taking my time and looking for possible causes. A guy at a rotary rebuild some in NJ said to check the ES and pull on it. I took a video. Because I know there’s some tolerances. Here’s three videos I took of the things. The end bearing. The starter. And a pig tail of the three I unplugged and one of them was broke in two. I’d like to know what that one controls
Finally found time to start pulling this guy out.. and everything is out except I’m having trouble with the top bellhousing bolts. I’ve read you can go from the bottom and use extensions to get the top ones.. this is near impossible. Is there a way to get them from the top. Any special tool that could help?
11-05-2017, 01:07 PM
