ECU Reset
 

Hey guys, New Poster,

I have an 06 Mazda 3i, 2.0 Liter, manual Tranny, no ABS, no AC, or power options.

Yesterday I changed out the spark plugs for some of the bosch PLatinum irridium +4 Fusion plugs. I disconnected and completely removed the battery, but didn't pump the brakes or turn on the lights. i used a Torque wrench to precisely tighten the plugs to manufacturer specs. After I got everything back together I took the car out for a drive and it was running absolutely horrible, it was backfiring, the engine was dropping off at shift points it felt like it was going to stall a couple of times, I thought maybe the car just needed to be driven to allow the ECU to properly reset, it did seemingly get better as the day went on, but i went under the hood several times to check the plug wire connections, to make sure there wasn't a loose connection. Now I drove it for a total of about an hour and a half yesterday after the change. I got in the car this morning and drove it around today, it felt better, it has stopped the backfiring and the feeling like it was going to stall, however the engine still seems to drop off when I shift from first to second.

Getting to the point, Usually how long does it take for the computer to completely reprogram itself? should I keep waiting for the car to clear itself up or should I start considering that I did something wrong and have the car looked at or switch the stock plugs back in . . .

Another consideration, when I was reinstalling the battery, I dropped a nut to the left and it got stuck underneath that electronics cluster and i used a rather strong magnet to pick the nut up, is there any chance that the magnet screwed with any of the electronics in that box . . .

the problem is caused by the garbage plugs you installed. ONLY USE NGK plugs in a mazda.

I'd suggest the Iridium IX's and nothing else (maybe the laser iridium's)

+1 I don't know what it is, because some cars run great on Bosche, but our cars strongly prefer NGK (or Denso, but not as many places carry Denso and when they do, they're way more expensive).

NGK copper here.. they might not last as long as iridiums, but I change my spark plugs far too often to need that longevity. I change them every other oil change (or sooner) so the copper lasts. I had iridiums but they didn't last me as long as they are said to because they just got a ton of carbon deposits on them.

+2 for NGK. Don't ask questions, just swap them out .. cuz no one really has a definite answer behind it. As Roddimus said the IX Iridiums would be a good choice (about $30 for all 4), or even the Platinums would be fine.

Yep. NGK FTW! It's not often that the OEM/inexpensive stuff is better, but you really can't go wrong with NGK plugs and wires. The RX-7 guys won't use anything else.

Yeah some people drop like 45 dollars on some wild bullshit Bosche --I spend $7.55 for all four copper NGKs (why bother with long lasting, our cars are so painless for changing plugs).

NGKs plug wires are pretty awesome, but you have a Mazda3 so no plug wires (unless just the 2.3 is like that)

Agreed on the NGK also. I'm not as fanatical as Kansei about changing them but I do it more than once per year.

I think the stock copper ones last.. to 30k miles? I dunno.. in 30k miles I've turboed my car and been naturally aspirated twice each so I had to get plugs all of those times :P

with a turbo car I'd suggest the coppers anyway. There's a few reasons why.

Like you stated earlier changing the plugs more frequently in a turbo car is ideal. It's a great way to inspect each individual cylinder to see how it's combustion looks.

Secondly, Copper plugs dissipate heat faster removing excess heat from the combustion chamber that can cause pre-detonation in some situations.


I only suggest the IX's in NA vehicles and suggest replacing them at least once a year. I do mine more than that but once a year shouldn't break anyone's bank.

spark plug connections . . .
 

You bring up another good point, the 2.0 liter doesn't have the typical plug wires either, I was wondering, can you replace the factory style cables, with some solid old fashioned clean looking plug wires . . .

or do the little factory wires go directly into the computer . . .

The little wires go directly to the ECU. You don't need plug wires because you have an individual coil for each cylinder, with no distributor or anything. So while you won't need to replace plug wires as scheduled maintenance, you will need to replace coils (they last longer though)

I just hate the look of those loose little wires though, lol, they could've atleast wraped them together in what would've appeared to be a typical spark plug wire, and then seperated them in the coil . . .

coil boots still need to be replaced but hardly ever.... like every 60k or so I'd think. I've never kept a car long enough to put 60k on it but thats when I'd do it.

Sounds more like you've got some spark plug wires mixed up.

no, if you've even looked at the way these engines are set up, you know there is no way to mix up these wires unless you like completely tear down the motor, that and I changed one plug at a time, refastening the boot after each plug was replaced, meaning I didn't just unplug all four wires and change the plugs, I put the wire right back on when I finished each cylinder.

but anyways, the car is running fine now, I think its just that my last two cars didn't have any ECU So I wasn't used to the car taking that long to re-adjust after the reset. I'm trying to find out where I could get some NGK plugs around here, will I have to order them and have them shipped or are there any retail stores in the Boston area that sell them?

o and when I went to the NGK website, the only plugs they had for my car were the irridiums, they didn't show any coppers like you guys were talking about. Is that just because I have the 2.0 instead of the 2.3?
Because the NGK irridiums were listed at like $12 which is no cheaper than the BOSCH, but I'm still going to switch them since everyone here recomends the NGK. and one other thing is that the stock plugs I pulled out weren't NGk, but they were FoMoCo (I'm guessing Ford Motor Company) part number ILTR5A 13G. Does the 2.3 come with these same plugs? or does the 2.3 come with NGK's?

Mazda3s don't have spark plug wires :)

though you could have plugged the wrong plug into a coil over a plug, as the guy said it would be nearly impossible.. you'd have to unwrap the wiring harness, solder an extension on, etc. The wires are only as long as they need to be to prevent that from happening.

Of course you can't see any of this on the MS3 without pulling the intercooler off so I wouldn't expect any MS3 owner to know yet :)

these are the stock plugs I pulled out . . .

Attachment 10204

Attachment 10205

Attachment 10206

Attachment 10207


Are those NGK's with Ford badging?

NGK V-Power FTW! less than 2 bux each. i would use anything else in mine

Anyone know what the deal is? I thought people said NGK was the OEM spark plug supplier for Mazda, but I don't think those are NGK plugs that I pulled out?

i dont think so either. just throw in ngk v power and drive it like you stole it. all 4 for less than 10 bux

I'm at work so I can't see the pics you must have posted of your plugs.. otherwise I could tell you what's up.

My original plugs weren't NGK, they were Denso.

Since the MZR engine is used by Fords, I'm not shocked (though I am dismayed) that you found FoMoCo plugs in your car.

I still haven't met a Mazda that didn't enjoy NGK plugs though :)

probably going to change mine today, chris are their tq specs for our plugs? i've always just used a regular ratchet

torque specs will be included on the box for the new plugs. aluminum head = hand tighten + 1/16th of a turn I think

how do you hand tighten a plug though.... i have a tq wrench so does it give actual #s on the box?

yeah, but they're really small numbers so hopefully your wrench is accurate (I know mine is for higher-torque applications so I would never use it for spark plugs.

Hand tight = don't use the wrench, just take the spark plug socket with extensions needed to reach the plug and just twist that by hand until it stops.

I could be an idiot, but I want to ask why are you changing your spark plugs so soon on a base Mazda 3? How many miles do you have on the car? Was it running badly before you changed them? I'm pretty sure you don't need a tune-up until about 60K mi.

i REALLY REALLY hope you change your plugs before 60K miles

^^word.

didn't think 25,000 miles was that early for a tune up, I was changing the oil and filter and air filter anyways, so I figured I'd do the plugs because its simple enough, that and I wanted to try out those new bosch plugs, but in retrospec, I would've gotten some NGk because thats what everyone around here seems to recommend.

I'm not familiar with the exact type of ECU (usually I work on motorcycles) but its a closed loop system so it can 'learn' your driving style and modify fuel delivery/ignition to a certain degree.
Even manufacturers programs are based on common code/pre-programed maps (OBD/OBD2)
The important thing is to get plugs with correct resistance as ECU gets a voltage feedback from 'stick' coils. (the only way to check they are working correctly is to measure primary peak voltage) If plugs had different resistance, the PPV signal will be incorrect and can cause problems.
You really didn't need to disconnect battery to change plugs, you could either leave ignition off or if your worried about screwing something up, disconnect the plug/coil assembly one at a time.
As for damaging ECU/electronics with a strong magnet, doubtful if any real damage could be done but I guess its possible to create a default setting in flash memory so could take a few miles to re-learn settings from sensor inputs.
PJ

they are NGK plugs. even VW's use NGK as oem plugs

Not bosch??? crazy

what is the plug part number for the iridium IX? i looked on the NGK site and had to go back to the 2005 2.0l engine to find a part number for the IX's. is this the right number and will it fit my 2008 3i ??

Part #: TR6IX
gap: 0.52
stock number 3689

You should't have had any issues, but since you did, try removing the battery for a minute or two and re-attaching it. Sometimes a module can get a bad reset signal as the battery terminals are arcing when making a connection. I've seen this happen with low voltage / dead battery issues too.

New plugs won't cause an issue unless you actually got the wrong ones... completely possible since the car is a 'new entry' for anyone's parts database. When looking at the plug, the length of the washer to the tip should be the same - and the length of the insulator that's holding up the tip should be the same length. Different manufacturers / materials can change this a bit, but the insulator length controls how much heat stays in the tip, too much or not enough can cause problems.

The only magnetic thing i'm aware of is a hall pulse sensor - one's used for the crank angle that's on the passenger side of the car (you can see the steel wheel with a bunch of teeth on it). Other than that there should be no magnetic sensor to get all screwed up.