500 miles on rebuild and... Injectors?
 

I recently picked up my rx8 from the shop after having the engine rebuilt. As far as i know everything was reused except the Housings and seals obviously.

I have just passed 500 miles on the break in and I'm starting to do pulls passed 8k. It seems like the engine cuts out at anywhere between 4k and 6k rpms sometimes higher. Its a short cut but its extremely noticeable. Im trying to remember correctly what the mechanic said pretty sure it was something along the lines of the secondary injectors not being used much and that it would clear itself out eventually. I've also been premixing pretty heavy at their recommendation of an ounce per gallon of marine 2 stroke.

So my question should i look into new injectors? could it be the premix creating the problem? Or are there any other possibilities? I did notice the exhaust sound almost seemed to becoming more from the middle of the car. I had them check the cat and he said it was fine but pretty close to its last leg. Could a clogged or partially clogged cat be to blame as well?

If your CAT is plugged or partially plugged you are going to screw up your engine. If the exhaust doesn't flow out properly you get a lot more heat in the exhaust ports and things cook very quickly

If there is any question you should inspect it at the very least...and replace or gut it if it is suspect

That was one of my concerns with the car being over 100k miles and the condition it was in when i purchased it. I had them check it and told them they could gut it if it was bad but they said it was fine for now. Im looking into a mid pipe regardless but if its causing problems i may have to buy one sooner than expected.

Update: last night i pushed passed 6k rpms and the cel started flashing. I also noticed a smell when i parked it not sure exactly what the smell was though.

Dude

Check your CAT.....

Ive got an Ap mid pipe on the way. Probably going to quit driving it till that gets here then.

Drove down the road today to pick my daughter up from school and the check engine light came on and has stayed on. I got the codes read and it came up with a misfire, gas cap and tune up codes.

Misfire: ignition coils or cat. Not sure what a tune up code would be, that's not a thing.

So the cat could be causing a misfire. Yeah it was a auto zone employee and i was in a hurry so didn't bother to ask he may have just said it needs a tune up. The plugs were said to have been changed with the rebuild. He did say he thought it wouldn't be coils don't remember his reasoning.

So coils on these cars last about 25k. After that they're unreliable. If you don't know, change them before they kill your engine.

I asked about coils, cats, and stuff that might need looked at and was told it was fine for the time being. Plan to upgrade to bhr ignition when i get more money. If i need to by replacements for the time being thats fine. you have a quick recommendation on replacements?

AutoZone BYD coils with the lifetime warranty are the going budget favourite. You may be able to find stuff cheaper knock-offs on ebay, but it's better to spend a few extra bucks than continue to risk the engine. BHR is obviously the going all-around favourite.

How did the original engine die? That might point to what's going on now. I still think the most likely fault is the catalytic converter. Is the shop that had it a known rotary specialist who can diagnose properly?

Just ordered these to pick up tomorrow CARQUEST by Intermotor Ignition Coil E1001: Advance Auto Parts. Im sure they have never been changed so it won't hurt regardless.

I bought it with low compression from a used car dealer. They couldn't get it started but i had a feeling it was severely flooded since they didn't seem to even realize it was a rotary. I got it started after a couple of hours and it ran rough but it would start and drive just the warm start problems. one day it started to over heat on the highway and by the time i realized it was to late. The plastic nipple for the over flow was broke off.

Colletti motorsports did the rebuild and i chose them from a recommendation on here. Its a 3 hour drive from where i live but i wanted to make sure i took it to the right person and I'm still confident i did. I have a used ap mid pipe coming tomorrow and I'm taking it back to the shop on Wednesday to get a check on the rebuild.

The coolant light is on but we are attributing that to bad coolant tank sensor since its always full. and the power steering went out but i cleaned all the connectors and hasn't done that since. I imagined it was all unrelated so not worth mentioning though. Again i know the cars older and wasn't taken care of very well before i got it so i don't think colletti is at fault on any of those things.

During the rebuild, was the lower intake manifold cleaned thoroughly? were the port sleeves and the linkages cleaned and free of carbon? Any time a Renesis is taken apart its crucial to make sure the manifolds are hot tanked or cleaned properly. The 5th and 6th port sleeves open at higher rpm's, allowing more air into the engine and if they're still gummed up with carbon, they may not work properly, causing driveability issues.

You're on the right path to finding a misfire. I read that you ordered new coils, but I would suggest new plugs as well. There's no reason not to and you can order a nice set of NGK wires for $17 from Rock Auto. Then you know all of the components in your ignition system will be new and should be hassle free.

I feel like he mentioned that very same thing about the 5th and 6th ports. Now that i remember i believe he said they put something on it that might have made them stick a little because after the rebuild it did sit for almost 2 months. He said it should clear up. Just came back to me after you mentioned that. Im still concerned though seeing as i wouldn't imagine that would though a cel?

Im already in the dog house for the parts i have bought lol. I have to pick very carefully because every purchase is a battle haha

I just read back your posts, you say your cat is on its last legs and that it cuts out at high rpm. Those 2 things make sense together, so just to reiterate what people have already said... it's your cat. If you don't want to do another rebuild, stop driving and gut or replace the cat.

Put on three new coil packs today and the cel went away. The wires were still in pretty rough shape so ill get around to those soon. one of the bolts snapped off to mount the coil so i had to break it through and put a new one in.

The bracket did get a little bent in the process but the coil appears to be flush for the most part. How bad can the bad be if the coil isn't in 100% contact. Like i said i plan on buying the bhr kit and if i remember correctly it comes with a new bracket. I just want to make sure nothing major can happen.

I also put on the mid pipe. Its a little ricey but i still love the sound and being able to here the revs. seems a little more peppy but its super wet out so i didn't really want to get on it to much. Was wondering if i should of used any type of gasket maker on the exhaust to help cut down on any leaks?

How does the cat look?
There is a crush gasket that's meant to go between the midpipe and header. Not sure if reusable, every time I've removed mine it was destroyed. Same for any foil paper cake style gaskets, they fall apart right on the car. Otherwise no sealant necessary.

The coil install sounds fine. So to confirm 3 coils no problem, 1 coil slightly raised? That's ok. Way I figure that bracket is primarily a heat shield anyway.

It honestly didn't look bad i almost want to say it was replaced at some point considering all the bolts also came off decently. That is without breaking anyways. There was a little ring/cone on the mid pipe for the mating point I'm guessing thats what your talking about and it looked decent as well.

As for the coils yes they are all flush except the one the bolt broke off has a little raise towards the top of the bracket.

I took it down to the shop for them to go over the rebuild and everything checked out. I also haven't had anymore hesitation after 5k rpms. The cel came on right after i left not even thinking about it it turned out just to be from the mid pipe. There was a little foamish type stuff on the dipstick which with everything going on i didn't even think to check. The mechanic said its normal with a rebuild due to condensation in the engine when put back together. He said should clear out after couple changes. That kind of left me puzzled because i have never heard anything like that and in my experience condensation was always bad or just anything besides oil in a engine is bad. I have no reason not to believe him though the car runs great and i really don't have much experience with rebuilds of any engine.

Thanks again though to everyone helping out on this post. I love these cars and I've wanted one since first scene one in 2003 and even more since my first fc. So i just want to make sure i do everything right.

The foamy stuff is condensation and it's fine. It will come and go depending on how hot your oil gets.

I figured i can keep my questions in here instead of making new threads or bumping ancient ones. If I'm not supposed to and this needs closed or something just let me know.

It is somewhat relevant to something i posted on here a while ago in that I'm still having problems with my power steering. Seems to be after gets wet or car wash and if i play with connections it seems to come back on except for last time it didn't. Ive cleaned them out with the electric parts cleaner all 3 if I'm correct and it lasted about a 2 weeks until just recently. Are there new connections i should look into? at one point before the light came on after a car wash i had power steering to the left but not to the right. Appreciate any help with this even if you just tell me to clean them again

Not so relevant I'm about to order a sohn adapter and install it within a few weeks. I know the premix topic is super debatable but i was wondering if the rules change with the adapter? I know people have said its fine to use synth for the engine since its not being injected anymore and ill probably do that but i plan to buy idemitsu premix what seems to be the preferred. Is that still the best for the sohn and gas tank premix or is there something else i should consider?

The power steering issue sounds like the connector is not water tight. Clean and dry it out, and see if you can heat-shrink wrap it or rub down the outside of the connector, fully closed, with bearing grease or similar. It's usually just that one connector.

Good idea on the Sohn adapter, you can Idemitsu or other stuff. Idemitsu can be expensive/hard to come by, but you have options: Klotz Techniplate, Protek-R, Lucas. Anything JASO FC/FD rated. Same as if you were to premix. It's not a bad idea to premix a little anyway, you might get more oil to the side seals that way.

I have some dielectric grease I can put on. Ill give it a try when it stops raining.

Ive read over what i think are the major sohn threads including i believe your diy write up. I looked at the kit from eBay though doesn't seem to come with the adapter itself. Is there an all inclusive kit? I don't have a problem pricing it together just thought might be simpler even if it costs a little more. I'm not the most practiced fab guy either so for looks alone might be better from someone else.

Would really like to incorporate this though so idk which route should go.
https://www.rx8performance.com/produ...y-canister-duo

Also is there anyway to get rid of the cel from the mid pipe until i get a cobb or rb flash? Still deciding and in the mean time that light drives me nuts plus i want to know if something else pops up.

Buy a MazdaEdit.....

Cobb has pretty much ended the support for the RX-8 and have made it very difficult to get the software to tune it yourself.

I had read that. Just went through a bit of the thread on the Mazda edit. Is it still 1100 and is there any tuning support for it? I'm not going to know how to do my own tuning so I was leaning torwrads rb rev2.