bsteimel

iTrader: (5)

Problem: I tried to start my car and at first it just spun but wouldn't 'turn over.' tried it 2 times about 3 or 4 seconds each time. Looked under the hood and made sure the battery was connected properly and if anything was out of wack, nothing. There was some small corrosion around the battery terminals though, but not enough to fret over. Got back in the car tried it again, it caught idled super rough and died. tried it again and it caught idled really rough and a lot of smoke out the tails. it smoothed out and the smoke kept coming out. A friend and I looked at it and decided it didn't look like coolant smoke. This has never happened before.

The Car: GT with 72,000. New battery, starter, plugs at 30k, plugs again at 60k. Haven't changed the coils yet. Water pump changed at 60k. Cat changed at 60k. Last oil change 1,500 miles ago. All fluid levels are normal.

Before: I just finished working NYC today, i live in west chester, about 45 min West from philly. its about 300m round trip. averaging about 85 on the way there in the morning and then driving through Manhattan traffic. Then came home again through Manhattan traffic and then 150m on the NJ TP averaging about 70mph. Went to a friends house for a few hours and then tried to leave. Air temp by the way is about 50 degrees outside.

After: took it for a high revving drive and a cool down. Idle was good as gold and normal exhaust afterwards

My hypothesis: carbon build up from a uneventful long highway drive and a bad day of city driving. The starter system is getting weak from the old coils and possible corrosion on battery terminal and couldn't turn the rotors fast enough with the carbon build up. Smoke was the carbon coming out.

To the Forum: Am i correct to assume that my scary starting was just from carbon build up from a day of hard driving or am i looking at a big issue? like low compression? Is this single incident enough to warrant a trip to the mechanic?

Thanks in advance

Also i searched around, but all the hard start threads seems to deal with flooding issues, cat clogging, high heat or fuel pump issues. i don't think they had anything like this.

Update: same problem this morning now with flashing CEL. Going to replace the coils and see what happens.

Replaced the coils and the baby runs like new. I didn't get a chance to take a look at the plugs, but when i tried to start it last time, i definitely flooded it a little bit. It was a bit hard to start and the exhaust smelled like gas. I drove it around and let and started it again and it started fine. I'll have to take a look at the plugs and make sure there not fouled at all. I couldn't notice any power difference, so i assume that i'm good to go.

jujo

72k on the original coils? D:

alz0rz

iTrader: (41)

wow.. uhm.. change the coils.

bsteimel

iTrader: (5)

yeah i've never had a CEL that showed a misfire, or hard starts until now. Only had 2 CEL's, bad cat and bad o2 sensor.

nycgps

iTrader: (1)

Consider yourself lucky that your coils last that long ...

Mazurfer

Yeah....coils!
While you are in there, take a look at the plugs just for the hell of it. Maybe take a pick and post on here. Only ~12k miles on them, so should be okay, but one never knows.

bsteimel

iTrader: (5)

Ok I still have problem after replacing the coils, plugs, and the plug wires.

When i replaced the coils, it started up just fine. I had also pulled the battery and done a PCM reset with the brake pedal. The next day it was hard to start and ran really rough with a flashing CEL. I figured that maybe when it didn't start with a bad coil i had maybe fouled one of the plugs. So i replaced all the spark plugs and wires. Again i had pulled the battery so the ECU had reset. THe car started like a dream. The next morning the car was NOT hard to start but ran really rough for about 20-30 seconds and then was completly fine and revved to 9000 and ran all day fine. Now after 2 days and a few drive cycles I got a flashing CEL. This was caused with the same symptoms started up fine ran rough for 15-30 seconds and then the car runs like new. Ran the code P0300.

So why after replacing the coils, plugs, and wires am i getting a random misfire only when the car is cold and running in a closed loop (or is it open i forget). Only when it starts from cold.

I researched on the forum and thought maybe i could have bumped the crank sensor, where is it so i can make sure its fine? Is it on the drivers or passenger side? When i changed the plugs i didn't even go under the car, i did all 4 from the wheel well.

swoope

iTrader: (5)

NVRAM (Non Volatile Random Access Memory)
NVRAM is a rather unique feature. The system memorizes the profile of the eccentric shaft plate on the e-shaft pulley. It basically knows how the e-shaft spins, on an individual basis, 2 cars NVRAM will generally never be absolutely identical, they're pretty close to unique.

As you'd imagine with such a specialized system you wouldn't want this information relearned and forgotten very easily, relearning the profile isn't a short process (drive cycle, dont worry you dont do anything special to relearn it). So this info is kept in a special area of the PCM it CANNOT be cleared in any way EXCEPT the proper procedure, you could disconnect the battery and do a jig for a year and it won't erase.

When/Why should you erase the NVRAM?
Realistically there are only a few times, generally the only times it's really needed is when replacing a motor since you'll be installing a new e-shaft position plate. Sometimes you'll also repair a misfire, yet the misfire code will return even with you not noticing anything, in those cases clearing the NVRAM will sometimes help. Also during PCM replacement it's good to clear it.

How do you reset NVRAM?
Here it is straight from mazda:

NOTE:2004-2008 and 2009 and later model year procedures are different.

2004-2008 Method

1. Turn ignition switch to "ON" position, but do not start engine.
2. Pump the brake pedal at least 20 times within 8 seconds after the ignition switch is turned ON.



thanks tecniks for that ^^^^^^^^^^^


do that, and check all plug and wire connections. see if it helps.

if not i would be thinking fuel pump next.

beers

bsteimel

iTrader: (5)

both after replacing the coils and then next day when i replaced the plugs I had done the brake pedal reset. I had disconnected the battery which reset the pcm and then also when i got everything back together and turned the car to the ACC position i also did the 20 brake pedal taps and saw the oil pressure gauge swing back and forth.

Razz1

Then you may have bad Apex seals or something else.

And this only happens when its hot so, electrical is fine, battery/alternator.

In the old days, a hard start when hot was the starter. However I haven't seen anyone post replacing the starter solved the problem with an RX8.

teknics

the '04s starter burned out and was too weak for its job, they were forced to upgrade, so by 05 the good starters were in all cars. Thats why you dont hear about starter problems, cause it already happened lol.

I dont feel i can accurately diag this problem given the fact that there are no ways for me to check stuff. Id rec. getting a test light on the coils, making sure you put the right wire on the right plug, and eliminating the ignition circuit first. Then load test your battery, check and clean connections at starter. With all that done if the problem persists there's a wide range of directions to go...

kevin.

Razz1

WRONG!

04's didn't burn out. (wrong terminology)

There are still several of them on the road like mine.

Yes, they were under powered. Just couldn't crank fast enough.

There year of his car isn't listed.

teknics

lol, go try to deflood a severely flooded car with an N3H starter, they literally BURN OUT, they'll take the harness with them too. They didnt turn fast enough because they weren't strong enough. Any electrical motor not strong enough for it's job BURNS out. Go hang on your window while you try to raise it you will *burn* out your power window motor.

anyone with a stock '04 starter still installed is on borrowed time or is very lucky.

thanks for playing, here's your prize...

kevin.

bsteimel

iTrader: (5)

If you read correctly all of the hard starts after replacing the coils are only when the engine is cold.
I had my starter replaced at 30k miles with the hard start TSB.

Because this only happens for about 10 seconds after i start the car when cold, i have no idea where to look for an answer. If i had the wires on the wrong plugs or a coil/spark plug was faulty it would happen more then just when i start it up. I made an appointment to take it to the dealer, we will then see what the problem is.

teknics

well we just got a customer come in complaining of an intermittent long hard start, almost like it wanted to flood. Engine was in the 6.0's all around on compression, that wound up being the solution. Her starts got harder as the car got hotter, when cold it would stumble before starting up, no smoke on any hard starting occasion. Hope thats helpful in some way lol.

kevin.

bsteimel

iTrader: (5)

Maybe it might be compression. But my starts don't get harder as it gets warm. When the engine is warm, there is no problems when it starts. And really it isn't hard to start, it just runs rough and throws misfire codes for the first 15 seconds when cold. After changing the coils, plugs, and wires, i don't have to crank it any longer then normal. I'm tired of replacing parts, its my daily driver, i need it on the road ASAP. So hopefully the dealer can at least diagnose the problem. If its the fuel pump or something similar, I'll pay the diagnose fee and do it myself. I go to nucar in Delaware and they are pretty dependable as a repair facility

swoope

iTrader: (5)

really,

04 with a original starter.. 107k miles on it..

still working fine, but i have to tell you i have not or cant flood it. cold start cold stop, restarts fine..

stall cold, restarts fine. guess i am lucky..

i dont understand how people flood this car?

beers

shazy

You are just one lucky son of a bitch then, Swoope.

bsteimel

iTrader: (5)

I took it to the dealer today and his first guess is a leaky injector. He is going to keep it till tomorrow morning to make sure.

Overnight the injector leaks and floods the one rotor. After the car de-floods the one rotor and gets going the PCM dials back the one injector after detecting a 'rich' situation and the car runs normal. This is why it only runs rough for the first 10 seconds and the car runs fine all the rest of the time. So no problem with the ignition system after all.

Hopefully this thread came help someone else that see's misfires only on a cold start for the first 10 seconds and the car runs fine all the way to 9000 RPMs. Before they replace the whole ignition system

dsire4u

iTrader: (5)

good thing that the dealer found the problem!

teknics

yea cold start problems on rx7s normally were leaky injectors. Id check the fuel pump's pressure holding ability. Your pump may be on the way out unable to hold the pressure over time so when you go to cold start it there's no fuel in the lines. that could expaining the rough runing if the pump is weak that it needs time to build up proper pressure.

kevin.

invasion08

iTrader: (7)

Still have the shitty 04 starter in my car. i wish i had the updated one

bsteimel

iTrader: (5)

spoke to soon, not a leaky injector. Kept it overnight and the injectors are fine. Ran a compression test, ran great compression. He did the decarbon TSB, John at Nucar is confident that will solve the problem. Not the greatest news in the world for a definitive fix, but i guess we'll see in the next week if a simple decarbon did the trick.

teknics

I have personally witnessed a decarb improve a motor's compression by at least 1.0kgf/cm2 (100 x kpa) which improves starting ability a lot. The only other things I'd think are do a test on the fuel pump's ability to sustain pressure (basically connect pressure tester w/ shutoff valve to fuel line, run car, turn off car, close valve, monitor fuel presue over 5 minutes. your pump may be letting the fuel drain back to the tank over time) or it could be a MAF going bad, TB going bad, intermittent vac leak possibly an improperly operating air pump at the most.

kevin.

bsteimel

iTrader: (5)

Finally found the problem. After a few months of on and off problems the compression was low enough for a engine change. I'm in the rx8 new engine club. It started off as an occasional misfire to low power, disappearing water, and regular misfire. Tried everything, engine cleaner, plugs, coils, wires. Checked all parts everything was fine. The compression finally just lowered until it was time to join the new engine club.