Chasing an interesting one.

First off, car starts. I had an issue with a cold starts, with battery voltage (measured by UltraGauge) drop down around 9.5 volts, but the car always started. volt meter shows 14 volts running, +- .25V

Very cold weekend, car started, but threw a 610 error and a wide band heater error. Issue was only when it was cold. Car runs fine. Had battery tested, battery was bad, car starts much better. Voltage does not drop.

After a bit, voltage drop is back, P-610 error is back (occasionally)

Front wideband finally replaced. Throws 610 on cold start. Once warm, does not throw error. But, now throws 610 on cold starts. Pain to clear. Car off, key one, clear, key off, start. You cannot clear it while the car is running.

Am thinking the 610 is related to voltage drop. But, cannot make connection to cold start. Heading out to get alternator tested. Also thinking up testing plan. I get one cold start to test, then all is fine. Ideas welcome. I am having a hard time making connections.

through all of it, the car runs great. I think the issue is related to the voltage drop, but cannot come up with what is causing it. Very few things could suck up that much power without exploding.

Thanks,

 

I also have the P0610 ... also only in the winter. Had it since winter 2010 ... after i refurbished my alternator (new bearings and paint)... so maybe u are right with the alternator ... but why only in the winter.

Car drives fine ... if i delete the CEL whe the engine is warm it only come back after let it sit a night in the cold.

Greetings
Thomas

 

@ Thomas,

Nice to not be alone. I had alternator checked, it is fine. Today, if it warms up, I am going to go after all the high current connectors. Battery, Grounds, any large wire will get checked and cleaned.

When it happens, I get a low voltage error on my UltraGauge, down around 9 volts at the ECU. My thought is that the power is not flowing well and the starter is sucking down the voltage for a fraction of a second and tripping the alarm. Kind of like a bad battery terminal, but someplace else. I think the cold makes the situation worse.

{EDIT} This seems not to be the case, the issue can be caused by simply turning on the car, not engaging the starter. I am still looking at power, but not high current power.

On your alternator, what did you touch? Just the wires that go into the alternator? I would not have thought they would have thought they would be involved, but apparently they were in your case.

Thanks,

Mike

 

How did you have the alternator tested? Bench tested?

 

@Mike:

I installed the engine in october ... i literally touched everything since i was rebuilding all parts of the engine (pics on my website: Fotos 13B Rebuild - infiltr8's Website) I know every Ground connection is optimum ... also tried to protect them from corrosion as good as possible .

I had some problems with the alternator not charging cause i accidently painted "too much" on the alternator housing. I suspect the big connector at the ECU.

Ohh .. and i had this every winter since years also before one complete rebuild and after. If the code is deleted if the ambient temps are about 10°C it doesnt come back until next winter.

Greetings
Thomas

 

@ 9K, not a bench test, tested on the car...

battery static voltage is about 12.6 volts. If the issue does not occur, the voltage drops to the low 11s while cranking on my ultragauge (this is the voltage the ECU believes, so likey measured at at the ECU). If the issue does occur, the voltage drops into the low 9's, the radio resets, and the CEL fires.

I just went through every high current connector and cleaned everything. I did see some pitting on the mating surface between the ground cables and the battery connector (brass connectors) that might mean something. If there is a poor connection, it will arc, then be a clean connection. I then tried a cold start, with a CEL. My stupid fat finger hit the clear menu as opposed to the what is the stupid code menu, so I do not know what the code was. However, it cleared. My experience with 610 is that it will not clear that easily, so it was possibly not a 610.

I started chasing the high current connections thinking an issue here would let the starter drop the system voltage, but other than the pitting, I did not find an issue. I did re-work how the cables mate and think I got a better connection.

I also did a break and mate on the connector going to the resistor think under the Air pump. If that is like the old school resistors, it can play a role in starting. I have a sneaky suspicion it is for the fuel pump high and low though.

I forgot about the alternator cable. Will pull and clean it tonight before the cold soak. What I really need is an analog volt meter and a buddy to be here when the issue occurs. I need to see if the actual battery voltage drops, or if the loss is a momentary resistance in the electrical system.

My brain just fired on bad windings in the starter solenoid. Some kind if situation where, if they are cold, they draw too much current from where ever they get it. I need to get out the schematics and see if that power comes from a relay, or out of the ECU. Then I need to see if I can remember how that solenoid works and if there is a current rush until the rod moves. Those text books are long gone, but maybe an EE can weigh in.

Thoughts anyone? Infiltr Eight, by any chance, you ever changed your starter?

 

When I had alternator issues (overcharging) it started randomly and it would start by overcharging at times and throwing all kinds of weird codes, the steering would mess up, etc. etc. then right after the voltage would drop (watching on a scanguage II at the time) and then the battery light would come on and the car would quit and I would get a bunch of random codes. Well finally one day **** went haywire and the overcharging exploded the battery all over my engine bay. The dealer tested it and said it was the battery (it was exploded remember, lol) and they wanted $180.00 for a battery and since it was only a few months old I refused and went to Autozone for another one under warranty. But after the new battery was in the same issues popped right back up I took it back to the dealer. The dealer again tested the charging system, said it was the battery again (brand new battery).

So since I knew the battery was not the problem I pulled the alternator myself, took it to an alternator shop and the guy put it on the bench tester and in two minutes told me it was bad. He rebuilt it and the issue was fixed. Except that the damage was done to other items, the overcharging ruined my ABS unit, interior lights, and drivers side power window switch, plus a bunch of fuses, etc to the tune of $2700.00 or so. Luckily my extended warranty covered it and I had the dealer (a different one) do that work since the ABS required a dealer programming.

I would go thru each item and if you can't find it, get the alternator tested.

 

thanks

It is occasionally going through the high voltage limit on the ultra gauge, but I have that set under 15 volts, and when it does it is just barely above. I set it the first time I heard your alternator overcharge story. What did you consider high voltage? My boat used to run ungoverned at 18 volts and never really had a battery issue. Everything else burned up, but the battery did fine.

My target right now is the starter. From the wiring diagrams, 12 V goes through the key switch, a few interlocks to the solenoid and is grounded through the ECU. The ECU has to sink any current pulled through the solenoid. It likely does this through its ground, and if the current is too much, it will raise that ground a few volts. To all intents and purposes, this lowers the voltage across the ECU, causing the issue. This is why it shows up on the ultra gauge. And, it may not show up anywhere else in the system. (Um, it was a bitch troubshoot this one some hardware at work, bad grounds suck). Since I changed the battery, the GROM adapter (stereo) has been happy. It used to reset on a hard start.

I am at a loss on how to best test. Getting a folks over, on a cold day, with analog meters, to monitor ECU voltage, battery voltage and system voltage, all synced to a half second event when i turn the key, just one time, is not likely. I may try to see if the condition will repeat if I get it to occur. I am not sure if it will or not. I know if the car runs for a few minutes, the issue is long gone. Maybe cranking in de-flood mode (accelerator to the floor) will keep it from starting and let me go for a re-creation...... I have one more cold morning before it warms up. This is a pain.

And, maybe pulling the starter apart and lubricating everything will help. If the gear is sticking, will that cause an issue? Cold grease will make it stick for a fraction of a second, right?

 

It could definitely be you starter, when I was having starter issues (with a brand new but old model 1.4KW Denso that was on the shelf) I was testing voltage ever the place and not getting anything within spec. I finally gave up and bucked out for a Series II starter and it was the best $400.00 I have spent on my 8 because my car starts with barely a bump of the key. So somehow the 1.4KW Denso was malfunctioning and just not up to the task (long crank times even with it being new and teh battery being new) I could have sent it back and got a refund but I got more satisfaction from throwing it away though, .

 

LOL

I understand the satisfaction with tossing something. Been there, done that. It will be cold one more day, so I will give it a try, then I have a week of warmer weather. Pulling the starter though and checking it out or lubing it, may be in the cards. Problem is, after the new battery, car starts wonderfully. Is 135,000 miles a lot for a starter?

 

@Mike: I never changed the starter ... still have the 11 year old small one. Cleaned and lubed it this year ... and i also have a brand new varta e23 battery.

If u suspect the starter.. i have a new one lying around here (2kW) ... can toss it in if u find out it was the starter at your car to verify. (<--- Is that a correct sentence? hmm .. Sorry for my bad english)

I'll look for the voltages today (especially when starting ... i can record it) and clean the ECU connector ....

Greetings
Thomas

 

I can't say I read it in the posts but have you drop tested the battery?

Cells die in batteries and can show a surface voltage of 12-14v but once a load is put on said battery it goes to **** and this is more prevalent in the winter/cold mornings.

Check out simple things before going crazy with high dollar assumptions.

 

@ Thomas,

If the starter change makes the issue go away on your end, I would be really interested in knowing that. The fact that you cleaned and lubed yours and still have the problem takes that option off the table for me right now. I am also thinking that your idea on the ECU connector, specifically the grounds, is a really good one as well. I am working this morning. Hopefully the car will stay cold until after my teleconference. I have enlisted the wife to watch the volt meter on the battery.

Mike

 

More data.

Cold start, just turn on key, threw the 610. started fine, battery voltage stayed above 10.9 the entire time. It is not the starter, I had only turned on the key. That did seem like a good theory though. After the one instance of the code, it did not happen again, even with just turning on the car. No cold days for a bit, so not sure what I will do. But, I will post if I discover something new.

Mike

 

@jtspells: I have a Brand New VartaE23 and the Voltage is fine while starting and idling.

@04Green: I`ll clean the connector and delete the code next weekend and see if that helps...

Mike... do u have any Gauges or additional switches wired in the car? I have 3 Gauges and an extra Fan Switch for my undertray Fan ... maybe theres the culprit ... don think so because they have there own circuits with own fuses.

Greetings
Thomas

 

@ JT, I missed your post. I had the old battery load tested, it was bad. New one and new alternator tests fine.

@ Thomas, I have an ultra gauge installed, it is what picks up the voltage drop. It reads the voltage the ECU is sends out. I also have the front fogs wired in as DRLs off the accessory circuit. But, if I turn them off, I still see the issue. And, I do have a voltage drop on the accessory line, because the GROM keeps getting reset. Issue there though is I think that when you crank the car, the accessory bus gets turned off for a bit, then comes back on. This really pisses off the GROM (MP3 integration via CD changer interface).

I am back to warm days, so testing is out. 68 degrees in garage, no issue. I reset the ECU connectors. I am seriously considering going to a stereo shop and getting a big *** power capacitor and running it across the ECU leads (with a diode) to see if that keeps enough power there during a start. Or, get a storage scope. I was able to drop voltage down to around 11.3 by turning on the lights, stereo, ac on high and putting my foot on the brake, but no 610 and no GROM reset. And, stereo was fine.

Next step is to confirm I can get an error without starting the car when it is cold. I just need it to get cold first. Maybe next week.

{EDIT} Confirmed, I can get the issue without starting the car. Just turning on the key.

 

Mike,

not that i hope for cold weather again. let me know if you need some hands..

you check for sketchy fuses in the area of issue? still working but burnt.

beers

 

Ah, I like the fuse idea... Anything that will be effected by cold should be suspect. And, self healing fuses are a PITA.

Merry Christmas

 

Removed the CEL and cleaned the ECU connector ..... now its not cold enough to come back or it was the connector at the ECU ... will see in a few days when it gets cold again.

Greetings
Thomas

 

Cool,

Been too warm here. I reseated the ECU connectors, but did not clean them. That might be next.

 

I have the same issue with my 8. Only throws a P0610 code when the it is cold outside and runs great all summer.
Haven't figured it out yet, but from reading the only thing that people seem to be having success with is a reflash PCM.
I'm probably going to bite the bullet and get the PCM reflashed at Mazda.

 

RX8 Club Australia ? View topic - Intermittent engine light

 

Team,

Thanks, these gave me a new place to look. Specifically at sensors. I changed the wide band 02, but did not change the down stream 02. As all of this started on a really cold day, and I did get an 02 related trouble code at that time, that might be related.

Also going to do the "clean the fuses" route, once I get time. It is finally getting cool enough for testing down here.

 

the only solution I've ever seen is to repair or replace the PCM, otherwise just live with it

 

Likely,

Or, just install a small heater under the PCM... This is cold weather only, and I live in Florida. And, there are only a few seeing this issue. Right now, the ones with the problem that can repeat are Thomas and myself. But, my dumb butt needs to replace O2 sensors more than once a decade.

On a different note, I friend drove my car after the coil over install, and remarked as to how much he loved the way the transmission shifted.