dorayee

Hey Guys,

Just wanna give an updated on my car. I got the battery connection fixed ( the mechanic replaced new caps on both end of the battery and tested the battery is working fine).

However I experienced another problem, when the rpm is very low (i.e. <1,000) while driving (hit the break, slowing car down) or simply just stalling the car with no speed (so low rpm), then Engine becomes unsmooth, vibrate, and rpm is flickering like losing power and almost shut down the Engine, Any Clue to check what might go wrong? fuel pump,fuel pump fuse? the Engine operate normally if i hit the accelerator paddle (yields high rpm like 5000-6000 rpm, but there is a lound noise coming out from the exhaust pipe, I REALLY HOPE THAT IT's NOT the ENGINE problem, since it's 113k ('04 AT Model), Pls help !!!!!!!!

Thanks!!!!

JinDesu

iTrader: (2)

The idle vibrations is most likely broken engine mounts. No idea how to check that (you could look at it probably).

Loud noise? What does it sound like? Any descriptions?

dorayee

Thanks!

It's not a very load noise per se when the car is in idle, it's just vibrate and the rpm is flickering btw 1000 rpm and less as if the engine doesn't have power, almost like lost power and the engine shut down but not there yet, any clue ?

dmc27

Power loss symptoms like you describe are frequently reported after a new ECU flash is done.

It's possible your car has been running on an older flash and the new one is causing this problem. Give it a few days before freaking out as it may go away on its own.

If not - PANIC!!!




Kidding, but if it doesn't clear up on its own you'll obviously need to look into it more. Start with plugs & coils and go from there.

Bigbacon

iTrader: (4)

clean the MAF and check your filter.

I had a crazy RPM issue where the needle would jump around between maybe 1000 and 700 while sitting idle and the car would shudder like crazy for a second or two and then stop and then repeat over and over until I started moving again.

I cleaned the MAF and replaced my filter and it went away mostly. Still have a tiny bit of vibration still but no more violent shuddering and RPM drops.

dorayee

Hey Guys,

Just wanna give an updated on my car.

1. The local mechanics replaced all four spark plugs ($350), car def runs smoother but they said there are still some misfire steps in the rotary engine at low rpm and they have no clues on that, and suggest me to follow up w/ the mazda dealer near ithaca

2. I called the mazda dealer and schedule an inspection on this coming Monday, the mechanic (who did my heater core replacement at the dealer a month ago) said it might be a transformer problem on the spark to cause that problem, and it should not be things inside the rotary engine to cause that, I really hope it will go that WAY!!!

3. I am really exhausted with that I had a car for about 8 months and no problem so far until the Dec about replacing the heater core, I am desperately missing my '02 9-5 saab (had it for 3 years and no problem at all), The constant worry about the maintenance issues just drains my energy so much since i'm a grad stu who have to deal with my own works are more than enough. It is very very fun to drive this cat !!! but I might have to sell it.

Thanks Guys !!!!

RIWWP

iTrader: (2)

1: $350 for spark plugs? You got raped. Plugs are $80 for all 4 from forum vendors here (OEM plugs, not cheap ones), and they take less than 20 minutes to install, really really easy.
Anyway, your coils could be shot as well, because if they aren't providing enough to the plugs, then the plugs could be firing weak and replacing them might not fix the problem. Coil lifetime is between 25,000 and 35,000 miles typically. If you don't know when they were last replaced, or it's been longer than that, then you need them anyway as regular maintenance, and it could easily fix your problem. The entire ignition system (battery/alternator->coils->plug wires->plugs) is only as strong as it's weakest point, and anything going wrong will cause loss of power, misfires, and a drop in mileage. Often failing coils causes the plugs to foul, and when not addressed, the cat to clog and fail. (And a failed cat can cause massive power loss, especially up high, your mileage takes a walk off a cliff, and your car is barely driveable as it goes critical.

2: don't let the dealer pile charges on. They will try. Coils are $35 each MAX (as low as $28 on specials from the forum vendors here), but dealers often try to charge $80+ each, plus another few hundred for the labor. They are easy to reach once you remove your intake, and nothing in changing them requires special tools. 20 minutes if you don't know what you are doing. Really really simple.

3: Get some local help. Lots of owners in NY. I see you are somewhat middle of NY state, but even a tank of gas and a case of beer as payment is far far cheaper than the hundreds or even thousands a dealer will try charging you for labor.

dorayee

Hey RIWWP,

Many thanks for the encouraging words! Yes I am in Ithaca, Central New York, 1 hour away from Syracuse, Elmira, Corning and Binghamton. So far I only saw one more RX8 in this town.

I do have to agree with you that I might been robed ($200 for parts and $125 for labor and further diagnosis, they said they jumped something and did a test run so that's why they said it is still some misfires in low rpm, +$25 Tax)

I did ask them about coils, they said they are all in good shapes ( I don't know that they did check them or not, since the guy mentioned that he is not an expert in RX8 and he consulted a computer database of my cat problem and it suggested to change spark plugs, so they did and I had old spark plugs and they all looked bad.

Thanks!

dorayee

OH !!!!!!! The mechanic also mentioned that I have to fix this problem, otherwise like you (RIWWP) said the CAT would be next to Go and would cost me too !!! hurrr

dorayee

Hey RIWWP,

1. I think you might right to the point! I just drove the cat to gym a while ago. Now no more almost lose power stuff at the stop sign, the needle rpm is stable slightly less than 1000 rpm, just a lit flicker above that but much much smoother.

2. The mechanic claimed the coils are in good shape but I doubted they checked them! Since I called the mazda dealer, the mechanic guy who did the heater core replacement for me told me, it might me the transformer issues on then spark plugs (Aren't these coils?)

3. Strange but true, I just noticed that the driver reader light is flicker in the same way as the engine vibrate when I just park the car (car isn't moving) so I might suspect about the COILS? Am I right ? :_)

Thanks!!

kersh4w

iTrader: (3)

if your battery was just replaced, your car might have some issues with learning idle again.

drive for a few days, it might disappear.

RIWWP

iTrader: (2)

"Consulted a computer database".

So yeah. Don't listen to him. If your plugs were fouled up, then yes, they needed to be replaced. However if he doesn't know about rotaries, he shouldn't be giving you advise. If he came on here to research, then he might have some ground to stand on.

That does appear to be a stabilizing of your idle, which if your battery was just replaced, it wiped all your fuel trims. Also, if you haven't ripped it up to redline recently under full power (1st and 2nd are find), do that and see if you can feel any bobbles in power. You might notice the engine running smoother afterwards as well. If your Cat is going, you will likely notice it starting to choke on the top end. If your coils are bad, you will probably get 'burps' here and there in the RPM range as they misfire.

He is probably referring to the coils, but again, doesn't know enough to really know what he is talking about. Coil testing, even by a dealer, doesn't tell you anything. The proper test for coils involves removing them and testing them with a multi-meter for resistance. An official dealer test will 'pass' any coil that has any connection where it needs it, and no connection where it doesn't. However, the resistance that the coil has will increase over time, and this is where they degrade.

For example, I recently replaced my coils, and tested all 12 of the coils that have ever been on my car (2 previous sets + the brand new set), and technically all of them were 'within spec' from a dealer's perspective. However the first set causes misfires all over the place, the 2nd set was starting to, but it fouled my cat before it got too much worse. The 3rd set is brand new. Notice how the resistance values increase for each set based on miles?

I set my digital multimeter to Ohms, and on the buzzer. The test guidelines dictate that
- between terminals A and B, there should not be 0 or infinity
- between terminals B and C, there should not be 0 or infinity
- between terminals A and C there should not be continuity, 0 to several kilohm.

~35,000 miles on them before getting a few misfires up high, no noticable power loss, replaced coils and misfires disappeared. Unknown order in the 8.
Coil #1: 800, 558, 645
Coil #2: 806, 557, 640
Coil #3: 814, 556, 647
Coil #4: 806, 555, 645
Remarkably identical in values across all 4, especially compared with the 2 other sets.

Removed set, ~16,000 miles, I don't know which one was in which spot on the 8. I should have marked them.
Numbers are A to B, B to C, A to C
Coil #1: 804, 536, 608
Coil #2: 805, 540, 629
Coil #3: 770, 542, 620
Coil #4: 805, 544, 622

Installed set, brand new, 10 miles on them, numbered from front to rear in installation position:
Coil #1: 712, 477, 561
Coil #2: 768, 482, 577
Coil #3: 723, 490, 566
Coil #4: 713, 497, 572



The brand new set has the absolute lowest values of any of the sets, and since it's Ohms, which is resistance if I am remembering correctly, then they have the lowest resistance, the original factory 35k set has the highest resistance, and the 16k set has slightly lower resistance than the 35k set.

Coil #2 on the brand new set has the highest resistance values of the 4 brand new ones, but still better than any of the other coils, so nothing better that I can swap it to.



The dealer will keep saying 'coils are good' until one of them fails completely and stops providing a spark at all to the spark plugs, at which point your car will be hardly drivable, sputtering, chugging, no power, unstable spin on the engine, etc... Potential for heavy engine damage at that point, depending on which coil failed.


If your headlights are flickering in intensity (but not actually flickering on/off), and the car is running, then your alternator has an issue. Coils have nothing to do with headlight electrical power. It sounds like your headlights (which draw more constant power than any other single component in the car) are reacting to fluctuating voltage, which is provided by your alternator.

Your alternator also provides power to everything else, including ignition coils, and if your alternator is going bad, then your coils could easily be having trouble getting the power they need to provide the plugs with the power they need, etc..

It's all a connected system. Only as best as the weakest point.

As soon as you can, today or this weekend, BEFORE you go to the dealer's appointment, go to Autozone, Advance, Pepboys, etc... most of them can test your alternator for free. If not free, it would be a tiny charge.

If your alternator is starting to fail, don't panic, you can get used or refurbished ones fairly easily. I would recommend posting in the Parts Wanted/For Sale forum at the bottom of the home page, and look for people parting out their 8s (generally the wrecked ones will score you an alternator, it isn't a hot item). The alternator itself is very easy to get to, and no special tools required. Just some wrenches. If you aren't willing to do it yourself, ask for help, even if you have to drive an hour for the help, you can save yourself a ton of money.

If you really avoid that, then it would be better to have 'your mechanic' that you referred to before do the alternator swap. He will probably be able to quote you a better price, and again, you provide the alternator, not him. Keep the prices down.



If your alternator is fine, then pull your coils (1 10mm socket, 1 12mm socket is all you need), and test them for Ohm resistance with a multi-meter ($10 from radio shack if you don't have one). Test each pair of prongs on the connection (A to B, B to C, and A to C). Compare them to the numbers I posted above. anything between the brand new set values and the 16,000 mile values and they are good. At or above the 16,000 values or 35,000 values I posted then they probably need to be replaced. Get them from one of the forum vendors here, take a few days for them to arrive, and a few minutes to swap them in.


If you cat is failing, then since you are out of warranty (80k for the cat), I would just replace it with a midpipe. Even the most expensive midpipe you can get (~$500) is 1/3rd the cost of a new cat ($1,400 or so, just for the part). If you are concerned about throwing a CEL with no cat, and not passing inspection, then add an AccessPORT for another $500 or so which can block the CEL. You are still $400 cheaper than a new cat, plus the ability to get new ECU tuning maps, more power, better sound, and shooting flames.


If it is none of the above and your engine is failing...well, the dealer is going to have to tell you that (the only thing they have to do that you can't) via a compression check. The dealer will give you an outrageous price for engine replacement, which you will ignore. Even with a 'blown' engine, a rotary is driveable for quite a while, though obviously not operating where it should be. It will give you time to figure out options and alternatives. Rebuilding this engine is a hell of alot cheaper than even a 4cyl piston engine, and if it only replacing some seals, it can be as cheap as $1,000 + shipping the engine back and forth. At the top end, which is basically getting a fully rebuilt engine, you are talking ~$3,800, including core charge. And that is other people doing the work. The engine is small, light, and only has 3 moving parts. Pulling it apart yourself is more of an option than you might think.


So I would get the alternator tested this weekend, test your coils as mentioned above, and if either of them has an issue, cancel your dealer appointment Monday. They will just waste your money.

Let us know.

dorayee

Hey RIWWP

I did go to Autozone to check the battery and alternator.

1. The battery is fine.

2. The ALTERNATOR is starting to fail but you can use it for a while that's what the guy at Autozone told me.
RESULTS : @ idle -Voltage = 13.91 (should be 14.5)
42 Amps
: @ 2000 rpm - Voltage = 14.23
84 Amps
There is a quite sharp noise under the hood, the guy said it might be an Alternator noise, it is a quite stable long horn noise (personally i don't think it's a Engine or something inside the Engine noise, since you can hear it when the car is idle.

2. I will try to deal with the ignition Coil tom as you said (4 of them). I have a question that Do we have to disconnect the neg battery cable ? Also Do you by any chance have pics and step by step on how to removal & install the ignition coils for RX8?

3. Where can I buy the IG Coils cheaper than $89.99 each @ Autozone?

4. All in all, I am really thinking hard to accept the trade in quote (~$6,000) from a dealer near Westchester PA area, it is very stressful for me from everything is going on around me.

Thanks again RIWWP, I really appreciate your help!

RIWWP

iTrader: (2)

Good to hear confirmation that the alternator is driving at least some of the issues. I would really cancel that dealer visit, as it will just cost you more money. If you can find a used alternator, or a cheap refurbished one, get that replaced before worrying about the other items. Your coils might be fine for now, but if your alternator is going, you have no way of knowing without pulling them and testing them, since they aren't getting the power they need from the alternator.

Really, deal with the alternator first.


Once that is taken care of, if you are not back to full power, THEN deal with the coils. And buy the coils from one of these vendors:
- http://www.mazmart.com/PartsList.aspx?id=32&n=NEW&m=6 ($140 + shipping)
- http://raceroots.com/index.php/produ...ntcqas7dddofa4 ($178 + shipping)
- http://www.finishlineperformance.com...cat=273&page=1 ($143 + shipping)
Those prices are for all 4.

No, you don't need to disconnect the battery to replace the coils. Just remove the filter box (a bit of force, but nothing complicated), remove the intake tube (don't bend or stretch the MAF sensor wiring), and the coils are right under where the intae tube was. Pop off the 4 connectors, use a 10mm socket to remove the nuts (don't drop them), slide the old coils off the mounting plate, put the new ones on (any order, they are all identical), plug the sparkplug wires back on (make sure you keep the wires in the same order, don't get them crossed.), secure them with the nuts you took off, reconnect the connectors, reinstall the intake, and you are done.

Full DIY here:
https://www.rx8club.com/showthread.p...light=DIY+coil




If you have AIM, I am on there as 'RIWWP', and will be sitting at a dealer for my new cat for a chunk of tomorrow morning, and will be connected.

dorayee

Thanks RIWWP

Just any DIY on how to change the Alternator ? It's ~$150 at Autozone.

daveStyle

I've a similar problem. My idle is about 700 and it drifts in and out of shudder.
I'm new to the RX8 world - so I guess I'm wondering what the idle should be?

RIWWP

iTrader: (2)

There isn't a DIY for the alternator on here. It's really too simple and too rare for anyone to have made one.


(I am writing this from memory of what I dealt with helping to change a water pump on another 8, which is right next to the alternator, so I might not have everything exact)
-Basically, pop the hood, remove the engine cover and the battery cover.
-Remove the battery (physically out of the car, it's in the way)
-Remove the battery box. This is easier said than done your first time. The battery box is a 2 piece deal, with plastic clips holding the top and bottom pieces together. It doesn't require much force to remove, but if you haven't found the clips, you can yank away on it all day and it won't budge. The bottom piece just removes with a few bolts in the bottom, I think they are 12mm, maybe 10mm.
- You may want to remove the intake as well. Your call on that. The dealer has my 8 atm and there isn't another 8 on the sales floor here for me to look at. I don't know how much it is or is not in the way.
- Your call on removing the strut bar as well. Easy to remove and replace, and could be in the way since I think it sits right over the alternator.
- So now the top of the front and the front of the top of the engine is exposed, with the alternator attached to the front.
- There are some bolts holding the alternator to the engine block, a bolt locking the belt tensioner in place, and a bolt to adjust the tensioner. Basically remove all of them.
- Get the belt out of the way. Your call on removing the belt or just hooking it low out of the way
- Slide the alternator out of it's installation place.
- Slide the new one in.
- You will have to torque down the alternator mount bolts probably. I am guessing you don't have a torque wrench for exact specs anyway, but make sure it's secure without excess pressure that might put too much stress on the engine block. Crack the block and the rest of this doesn't matter any more. I would recommend checking the bolts after a few hundred miles of driving to make sure they are still tight, vibration will try to loosen them, and if they loosen, the belt will probably come out of perfect line, causing belt wear, belt failure, and damage other stuff.
- Replace the tensioner loosely
- Replace the belt, make sure you follow the same path that it was on before.
- Tighten the belt appropriately. I believe the standard is taking the middle of the belt's longest section and twisting it with your fingers. You should be able to twist it 90 degrees, but not more. Can twist it past 90 degrees? Tighten more. Can't get to 90 degrees? Loosen a bit.
- Replace battery box, battery, intake if you removed it, engine cover and battery cover.

Somewhere on the site here the repair manual is posted that probably has more detailed steps.

Easy though, no jacking of the car, plenty of room to work with once you get the intake and battery out of the way.

RIWWP

iTrader: (2)

Thanks for searching!

750rpm is standard I believe. Some people increase it to 850, 950, 1,000, or 1,100, though usually for boost related reasons.

If nothing changed with your 8 recently related to electrical or ignition, then your coils and or plugs might be starting to fail. Unstable idle is one of the first issues to pop up. You can get unstable idle for a bit if you just reset your fuel trims (battery disconnected or deliberate clear).

Bad gas is also a possibility, as is a dirty MAF sensor.

Keep an eye on it for a while. If it starts getting worse or you start seeing misfires or power loss elsewhere in the RPM range, it is almost certainly your ignition system (might as well do plugs and coils at the same time generally). If it gets better, it was just a fuel trim out of sync a bit. If it stays pretty much exactly the same, try cleaning your MAF (bottle of MAF cleaner from auto parts store for a few bucks, pull the sensor fromt he top of the intake tube, spray the hell out of it. Let it dry, reinstall). If it fluctuates all over the place and suddenly gets better after the next fillup, it was gas related.

ShellDude

iTrader: (12)

32000 miles 04 started noticing the 750 rpm shudder a couple weeks ago... I'm certainly confident my problem is coils and plugs (all stock original equipment). I've got some yukon coils and new plugs I've been meaning to install for the past year *gasp*... will have to make it a priority just as soon as it warms up a little... Got the MAF spray too so I'm thinking one step at a time.

I've got a catch can I'll be installing (NA -- no FI) but figure it can still help being that I try to top off my oil and my MAF has never been cleaned...

Will try to remember to report back behavior changes as I take on each piece.

I tried earlier this evening to "Squeak" by by going into ATR Race and bumping up my idle to 1000, but apparently once you go into gear those tables are ignored. I know this is one big fat ugly work around and will probably revert back to the defaults (or find the addiitonal setting to bump it up temporarily) until I can start with my replacements.

This all sounds very familar to me... numerous threads here that tend to tie this problem back to MAF, coils, plugs, 04-05 **** poor oil diversion, etc, etc.

At some point I need to figure out Jeff's dwell improvements with these BHR coils too... hopefully he can edumacate me on it at some point.

fun fun

dorayee

Hi RIWWP

Just a very one quick question, My car was in 5W-30 for all the time I owned it, the dealer i bought it from used it and so did the Monroe guys that I have services with, Any serious problem will follow? and I should flush it change to 5W-20, right?

About my car, I drove it yesterday for quite about 2 hour in cruising mode (no red zone), the rpm is about 800 when it's in neutral and P (when i start from cold engine it's about 2000 and drop to 800 when the engine is warm), It did have a vibration and go away when i drive it. So here is what i'm thinking to do tom

1. Take to dealer tom Get the compression test (I know this might be the stupid idea and waste of money but i would know for sure what's going on under my rotor it's 113k now, so high miles)

2. I will try to negotiate to $100 (instead of $200) for the compression test (some thread said use power diagnosis instead ?) and Change the IG Coils ($200 part) Wires ($95 part) the labor costs for those two is $89 (Spark plugs changed already)

3. Any suggestion to check? Motor mounts? CAT clogged? (my local mech said CATs is ok) MAF?

4. Should I change to 5W-20 ASAP? if so I would let them

Thanks!!!

RIWWP

iTrader: (2)

Oil: 5w20 is only a recommendation from Mazda. Mazda has never specified a given weight of oil that is mandatory, or even designated a weight of oil as prohibited. 5w30 is the recommendation Mazda gives outside of the US, if it helps sooth your nerves on that. No need to flush though, all oil weights are completely compatible with any other oil weight. I use 10w40 in the spring/summer/fall, 5w30 in the winter. All oils break down over time though, losing viscosity, so I generally top off with 10w40 in the winter, and when I can find it, 20w50 in the summer. Provide a boost to the dropping viscosity.

There are other options I'm not going to go into right now that I will be trying soon.


Compression test: That's your call, as long as you feel it's necessary then you won't feel like you are wasting money. Knowing the numbers is useful as well, as the better the numbers, the longer you can expect your engine to last. Gives you a good baseline.

Coils, Wires: I think you are overpaying, both parts and labor. If I was doing the same swap, it would cost me ~$200 for everything, not ~$385. If you are comfortable with it, it's ok, it's your money.

Motor Mounts: They certainly can fail, although their symptoms aren't generally what you described. When one or more motor mounts fail, the idle RPM is fine but the car itself is physically shaking. Stiffer motor mounts can improve throttle response and gear engagement, so if they fail I can see some issues in those areas, but you haven't mentioned anything that would suggest that is an issue on your car.

Cat: Cat certainly could be clogged. It's fairly hard to verify without pulling it however. Likely your mechanic just took the lack of CEL as "ok". Faulty analysis at that point, since it doesn't mean anything. I didn't get a CEL for my cat when it went to nearly 100% blockage. And you can get a CEL for your cat when there isn't a problem at all. At 113,000 miles though, I'd bet that isn't far from failure if it hasn't failed yet, unless it was replaced at some point previously in it's life that would extend the expectancy. The high heat of the rotary plus the extra fuel the OEM flash adds to help cool the exhaust are each very hard on cat life. Remove the excess fuel, the heat will cook it faster. Add the fuel, you burn through the catalyst faster. A single flooding has been known to destroy the catalyst.

MAF: MAF is easy to clean, just grab a $5 bottle of MAF cleaner from the autoparts store, disconnect the MAF harness from the MAF, unscrew the 2 screws holding the MAF to the tube, pull out the MAF, hose it down with the MAF cleaner completely from all angles. Let it dry, put it back, put the screws back, reconnect the harness. Done.

Again, don't worry about the oil. You are fine.

dorayee

Hi RIWWP,

I forgot to mention that, When The car isn't moving, but I change from "D" to "N", I did notice a significant no vibration from the Engine, any clues? The needle rpm dropped slightly to 700 and back to 800.

Thanks!

RIWWP

iTrader: (2)

"a significant no vibration from the Engine,"

???

Not sure what you mean here. The RPM dip is normal. If you are describing a faint 'lurch', keep in mind that Automatic transmissions have constant force applied to the drivetrain in D, shifting to N relaxes that force

dorayee

Ahh, I see about the RPM dip then. Well it just means that Engine is smooth (not vibrate anymore) when change from "D or R" to "N" Dose that help or clear? basically the engine vibrate (or shudder ) in "D" or "R" without moving it, and that vibrate/shudder is gone in "N"

RIWWP

iTrader: (2)

That sounds normal.

When in D or R, the engine is spinning the input shaft, which is spinning the transmission fluid inside the torque converter, and the fluid spins the output 'vanes' (I don't know the technical terms inside an automatic transmission), which spins whatever gear you are in, down the driveshaft to the rear diff to the axles. Holding the car stopped when in D or R, the unput shaft vanes are spinning the fluid but the fluid can't spin the output vanes, due to the brakes holding them in check (since they are solidly engaged to the rear axle). This is an amount of stress on everything that is accepted by the industry. Shifting to N disconnects the output vanes from the rear axle, as no gear is engaged, so the fluid spins the vanes freely, no stress there.

Hope this makes sense.