Hello fellow people,
I have a S2 R3 2010, 65000km or 40k miles for the US peeps.

About a week ago,
I swapped out coils, plugs , wires etc to the BHR kit
Oil change & Filer

After installing the BHR kit the car drove much better, it was really smooth especially towards the lower rpm and noticed the car felt much more responsive.
A couple of days later that all vanished, it seems to struggle around low to mid.

So I changed the air filter & fuel filter today, also cleaned the throttle body which did not give me that smooth responsiveness like I wanted from when the BHR kit went in.

Where should I be looking?
I have a custom exhaust system with a high flow cat, so I doubt it can be the cat?
Compression? never have an issue starting hot or warm

 

Any codes? Can't help but think CAT.

 

Hey Shumster,

Haven't checked for codes, Ill have that done on Monday!
Cat?, hmmm it already has a high flow cat on it but I guess it can fail

P.S nice R3 too, love the height!

 

Ya, my understanding is that most aftermarket cats can't handle the heat of the rotary and that in fact the oem cat is the best.

If you have your OEM coils it might be worth just switching back to see if it helps. I got a used BHR kit which ended up having a failing coil and I had similar symptoms. Luckily Charles, sent me some replacements and it fixed the issues!

I guess, do you have a CEL? Also might be worth looking under the car at night to see if the cat is glowing. Haven't flooded recently or anything have you?

Also how are your starts? Compared to when you were on OEM coils?

Thanks, haha I need to get some coilovers, but ya she sits pretty nice on the stock bilsteins and tein stechs. She does pretty good at the track too!

 

I see, haven't had any codes at all.

Ill look into the cat but I don't think it is it but anything is possible. no red glowing I took it for a hard drive yesterday night.

No OEM Coils , no flooding I always ensure warm up's are done until that first bar (red one) on gauge goes away before driving.

Starts I can say are much better. On the stock ignition system I had trouble on warm/hot starts it would take 5 seconds to crank. But with the BHR kit in does it in a flash. Maybe the fault could lie in the BHR kit? I just want that smoothness down low back upon installing the BHR kit it felt responsive down low. Still no problem getting to Redline though.

Oh I'm getting Tein Z Flex Coilovers installed on Wednesday so Ill put up some pics

 

Hmmm, this probably isn't what you want to hear but from what you said about the starts I can't help but think compression. The BHR coils might actually be covering up the start issues.

Classic low compression symptoms are low end power and hot start issues. Then the fact that you say you have no problem getting to the redline kind of rules out the cat.

How long have you had the car? 2nd, 3rd owner? Where are you located. Luckily you've got a 2010 so you're still under the 8yr core warranty.

 

2nd owner!, Located in Australia. I don't know if its covered under 8yr I believe its 5 here.
I will book in Mazda to do a comp test next week also and see what happens.

Really don't hope its that.

- Just took it for another drive,
also seems to be sluggish around 5-7000 rpm. Feels like its holding back.

If the cat is bad, does it make any weird noises?
I don't know its normal but my car seems to pop here and there when idling too.

 

Ya I hope that isn't the case too. No the popping at idle is normal. Just the Rotary!

I think you are right about the 5 year in Australia...unfortunately

Would you say the power loss is smooth or like choking (jerky)?

 

Loss of smoothness,
it just feels like its restraining itself down low to mid.
When I changed the coils, plugs etc firstly about 2 months ago it was really smooth and responsive.
After a couple of days it also vanished. I purchased the BHR kit last week put it in smoothness and responsiveness were all back ( down low ). So been through 2 sets of coil packs and wires + plugs in less than a month.

Unless the coils are failing again?, compression would be consistent though wouldn't it? like even after changing plugs etc it wouldn't make a difference.

 

Hmm that is very interesting, I wish someone more experienced than me would weigh in...

The sudden change is definitely confusing.

Maybe O2 sensor...?

Could you post a video?

So it only seems to fix itself for a few days before it goes back to sluggish?

Actually another suggestion would be to email Charles at BHR. He is really busy so it might take some time for him to get back to you but he is a great resource and a good guy

 

Booked in a comp test with Mazda on the 8th of January as its the only time suitable between myself & them. Yeah ill send Charles an email & see what he thinks.

I will try to get a video up today, Driving it today it again felt really sluggish all around it just doesn't seem to be giving that smoothness of power. I gave a WOT in 2nd and the rpm took longer than usual to climb. Bugs me to think every upon changing the coils etc twice the smoothness & response I'm after comes back then just all of a sudden finishes.

 

Emailed Charles! to see if he can give me any info.
Ill await his reply. But other than that looks like Ill have to wait till the comp test

 

I would definitely check the cat. The only aftermarket cat that I know of that can stand the abuse of a rotary is made my HJS, and it is very expensive.

It is also worth checking the coils. You can test them with an HEI spark tester tool. Before you do that, make sure your coils are matched to the appropriate plugs and are affixed tightly. Everyone makes that mistake at least once. Also make sure your plugs are torqued properly. A loose plug can do what you are describing.

Compression could be the issue, but there are a lot of other things to rule out before jumping to that conclusion.

 

Thank you Steve!
How do I check for a bad Cat? I don't get any glowing (Red) after a hard drive?
Differently will check out the other things!
Much appreciated, merry XMAS!

 

@Shumster
Fitted the Tein Z Flex Coilovers, 2 words..... Insane Handling =P.

 

The best way to verify is to jack the car up, undo the bolts and shine a light through.

Do you have a means of monitoring the engine via obd2?

Edit: and it's not unheard of to receive a damaged coils new in the box. Verify them by purchasing a coil tester from your local hardware store.

 

What fuel are you using BP Ultimate 98?
Where in Aus are you?

 

The whole cat does not glow. It has a cover around it. The only place where the actual cat metal shows is around the O2 sensor. It's on the left side of the cat. Look at the cat from the left side of the car and try to find the O2 sensor. It's plugged into the cat. If the cat is glowing, it should glow around the sensor connector as a small 'O' shape. About 1.5 inch in diameter maybe. It will have to be reasonably dark for you to see this.

The easiest thing to do is get a cheap Bluetooth OBD2 scanner, pair it with your phone (has to be android), download the Torque app and check the cat temps. Take it for a hard drive and post the peak temps here.

Finally, you can drop the cat and visually inspect it. But just because it looks good on one side doesn't mean it's not melted on the other side.

 

Hey buddy,
In Sydney!
Yes BP 98 always!