DIY: Mazda Ignition Coils (with pics)
03-21-2010, 03:13 PM
#76
Other data from other places.
I used this DIY for my coil removal, Great work.
Additional Data 1:
Some of the other threads and groups have talk about the white spots being "normal" on the backs of the coils. This may be so, but the ones I had with bad white spots on the back also had discolored spots on the metal plate under them. No way is that normal. Plate was clean under the other two.
Additional Data 2:
Someone somewhere (Bigbacon I think) mentioned the chirp when starting the car. With the hood open, I started the car. There were two distinct chirps, kind of like if you stepped on a small song bird. When I changed the coils, there were two with very large white spots and the above mentioned spots on the bracket. When I changed the coils, the squished bird sounds went away. Car ran better too.
I am going to try to find the other thread and back up the squished bird claim.
Additional Data 1:
Some of the other threads and groups have talk about the white spots being "normal" on the backs of the coils. This may be so, but the ones I had with bad white spots on the back also had discolored spots on the metal plate under them. No way is that normal. Plate was clean under the other two.
Additional Data 2:
Someone somewhere (Bigbacon I think) mentioned the chirp when starting the car. With the hood open, I started the car. There were two distinct chirps, kind of like if you stepped on a small song bird. When I changed the coils, there were two with very large white spots and the above mentioned spots on the bracket. When I changed the coils, the squished bird sounds went away. Car ran better too.
I am going to try to find the other thread and back up the squished bird claim.
03-21-2010, 04:52 PM
#77
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i did this worked great i took it on the road and was alright then i noticed it almost died at an idle and was idling a little lower then normal. i havnt driven it more then a mile after the change so maybe it needs to get used to it because the previous ones had 70,000 miles on them
06-18-2010, 03:38 PM
#78
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I'm going to replace my own coils, wires and plugs. They wanted $1100 to change the plugs and coils. They claimed you can't get the plugs anywhere else. They want $79/ each for one of the plugs, $52/each for the other and $63/each for the coils. The balance is the installation charge.
So has anyone found a source around $30/each for the coils as stated earlier in this thread? I've already found the plugs for $20/each.
TIA
06-18-2010, 07:50 PM
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07-29-2010, 11:05 AM
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Ok, just changed my coils, HT leads and spark plugs today, and now I'm pulling my hair out! Hopefully one of your guys will be able to help.
Engine now starts easier than ever, idle is much smoother, but at 7k RPM there is a sudden dip in revs despite me gradually depressing the gas pedal in a linear fashion. I can push it above 7k by putting in a lot more gas, but I daren't go any further as the engine sounds as if it's struggling, perhaps pre-detonation, but I've never actually heard it before so couldn't say for sure!
I've checked the obvious, i.e. all HT leads connected in the correct positions between plugs and coil packs, as per the drawing earlier in this thread. I haven't yet taken out the plugs to make sure leading and trailing are in the correct positions, but I only did one at a time and was very careful to double check along the way.
Before I go to all the effort of removing the plugs, is there a certain order the coils should be fitted? I ordered a new set of 4 (part number N3H1-18-100B-9U), although I noticed at the time of fitting that the old coils had a small number stamped in the plastic just around the base rim of the HT lead socket. Two of the old coils were marked '1', and other two were marked '2'. Unfortunately I didn't take a note of which went where.
The new coils that were supplied to me as a set had numbers 1, 2, 4 and 4, so naturally I assumed that it wasn't important which coil went where. I made the assumption that they are all the same. Now I'm wondering if I've made a mistake in fitting these, or perhaps I've been supplied the wrong parts? Any advice would be great, as I need to get her up and running again to drive to work in a couple of hours. Really should have saved this job for the weekend...!
EDIT: I've also now checked the plugs - I haven't removed them, but can see the part numbers, leading and trailing plugs are definitely in the right place. Just started the car again and tried revving up to 7000, for some reason the hesitancy to rev past 7000 has disappeared, but I'm getting popping sounds as the revs drop back down. Engine also seems slower to drop revs after letting off the accelerator than normal.
Edit 2: Hesitancy at 7000 is back again, along with the engine generally running and sounding pretty rough when near or bang on 7k. Have put back in original coil packs and HT leads, again still no joy. New plugs are still in place, but pulled out L1 and T1 to have a look. They are intact and not damaged, but after only having covered about 10 miles of testing, L1 was already a little tarnished and mucky. The old plugs were quite well blackened. Could a fuel mixture that's too rich be causing these issues around 7000 revs? The popping sound when the revs are coming back down does sound a bit like the ignition of unburnt fuel. Again should point out that this is with no load on the engine, I haven't been out for another drive yet as I don't want to push the engine if it could cause damage.
Engine now starts easier than ever, idle is much smoother, but at 7k RPM there is a sudden dip in revs despite me gradually depressing the gas pedal in a linear fashion. I can push it above 7k by putting in a lot more gas, but I daren't go any further as the engine sounds as if it's struggling, perhaps pre-detonation, but I've never actually heard it before so couldn't say for sure!
I've checked the obvious, i.e. all HT leads connected in the correct positions between plugs and coil packs, as per the drawing earlier in this thread. I haven't yet taken out the plugs to make sure leading and trailing are in the correct positions, but I only did one at a time and was very careful to double check along the way.
Before I go to all the effort of removing the plugs, is there a certain order the coils should be fitted? I ordered a new set of 4 (part number N3H1-18-100B-9U), although I noticed at the time of fitting that the old coils had a small number stamped in the plastic just around the base rim of the HT lead socket. Two of the old coils were marked '1', and other two were marked '2'. Unfortunately I didn't take a note of which went where.
The new coils that were supplied to me as a set had numbers 1, 2, 4 and 4, so naturally I assumed that it wasn't important which coil went where. I made the assumption that they are all the same. Now I'm wondering if I've made a mistake in fitting these, or perhaps I've been supplied the wrong parts? Any advice would be great, as I need to get her up and running again to drive to work in a couple of hours. Really should have saved this job for the weekend...!
EDIT: I've also now checked the plugs - I haven't removed them, but can see the part numbers, leading and trailing plugs are definitely in the right place. Just started the car again and tried revving up to 7000, for some reason the hesitancy to rev past 7000 has disappeared, but I'm getting popping sounds as the revs drop back down. Engine also seems slower to drop revs after letting off the accelerator than normal.
Edit 2: Hesitancy at 7000 is back again, along with the engine generally running and sounding pretty rough when near or bang on 7k. Have put back in original coil packs and HT leads, again still no joy. New plugs are still in place, but pulled out L1 and T1 to have a look. They are intact and not damaged, but after only having covered about 10 miles of testing, L1 was already a little tarnished and mucky. The old plugs were quite well blackened. Could a fuel mixture that's too rich be causing these issues around 7000 revs? The popping sound when the revs are coming back down does sound a bit like the ignition of unburnt fuel. Again should point out that this is with no load on the engine, I haven't been out for another drive yet as I don't want to push the engine if it could cause damage.
Last edited by electronicsuk; 07-29-2010 at 12:56 PM.
07-29-2010, 02:56 PM
#86
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Just tried resetting the fuel trims courtesy of this topic, and touch wood, it looks to have solved the problem. I've only driven the car to work so I guess it's a bit soon to say anything for sure, but right now the lumpyness around 7k has gone away and there seems to be no loss of power. Hopefully this will be of use to anyone else having the same problems.
Of course, I now have to re-fit the new coil packs and Magnecor leads again tomorrow, and will probably do another reset after that. I'm loathed to mess with the ignition system again now everything seems normal, but I can't leave £200 worth of brand new coils sat in a box in the garage.
Of course, I now have to re-fit the new coil packs and Magnecor leads again tomorrow, and will probably do another reset after that. I'm loathed to mess with the ignition system again now everything seems normal, but I can't leave £200 worth of brand new coils sat in a box in the garage.
07-29-2010, 04:20 PM
#87
WTF.Help! aFTER CHANGING PLUGS AND ADDIN A NICE SET OF 8.5 mm WIRES I WAS TIGHTENING THE LAST SCREW ON THE COIL AND WTF....BROKE IT.DOES ANYONE KNOW HOW TO GET OUT THE OLD PIECE?IT S FLUSH WITH THE COIL ITSELF.THE ZIP TIE AINT GONNA LAST AND IF I KICK MYSELF ANY HARDER I LL END UP IN THE ER.THANKS FOR ANY INPUT
07-30-2010, 02:58 AM
#89
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WTF.Help! aFTER CHANGING PLUGS AND ADDIN A NICE SET OF 8.5 mm WIRES I WAS TIGHTENING THE LAST SCREW ON THE COIL AND WTF....BROKE IT.DOES ANYONE KNOW HOW TO GET OUT THE OLD PIECE?IT S FLUSH WITH THE COIL ITSELF.THE ZIP TIE AINT GONNA LAST AND IF I KICK MYSELF ANY HARDER I LL END UP IN THE ER.THANKS FOR ANY INPUT
07-31-2010, 03:47 PM
#90
Revi update,broken coil stud..
Fixed the broken coil stud by removing the whole plate,knocking off the stud from the back and tack welding a new stud on...like new.Lesson of the day...dont over tighten when doing your coils...I think the metal is weak.Any way with the new 8.5mm wires,new plugs and new coils...AND a Revi ram air into the de walled,k&n filtered box the car is quite a bit more responsive to say the least. 2007 blk/blk
07-31-2010, 09:40 PM
#91
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Replaced my son's RX8 coils today using this DIY.
No problems.
I found some BWD coils at O'Reilly Auto Parts.
They are made in Japan and have a limited lifetime warranty!!!!
http://www.oreillyauto.com/site/c/de...2767&ppt=C0334
No problems.
I found some BWD coils at O'Reilly Auto Parts.
They are made in Japan and have a limited lifetime warranty!!!!
http://www.oreillyauto.com/site/c/de...2767&ppt=C0334
08-03-2010, 11:53 AM
#92
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Installed the BHR coils over the weekend. Wow! It's like having my original RX8 back! No funny chirping when the car starts and it feels like it's running on 4 cylinders instead of 3. 
I replaced 3 of the 4 plugs at the same time. The front trailing plug didn't want to budge when I tried to remove it. Gave me that sick feeling like I was going to do some damage if I tried any harder to get it out. Not sure if I just had bad alignment with the plug socket or??
Might take it to the dealer or a local rotary shop and see if they have any better luck.
I replaced 3 of the 4 plugs at the same time. The front trailing plug didn't want to budge when I tried to remove it. Gave me that sick feeling like I was going to do some damage if I tried any harder to get it out. Not sure if I just had bad alignment with the plug socket or??
Might take it to the dealer or a local rotary shop and see if they have any better luck.
08-03-2010, 01:20 PM
#93
Installed the BHR coils over the weekend. Wow! It's like having my original RX8 back! No funny chirping when the car starts and it feels like it's running on 4 cylinders instead of 3.
I replaced 3 of the 4 plugs at the same time. The front trailing plug didn't want to budge when I tried to remove it. Gave me that sick feeling like I was going to do some damage if I tried any harder to get it out. Not sure if I just had bad alignment with the plug socket or??
Might take it to the dealer or a local rotary shop and see if they have any better luck.
I replaced 3 of the 4 plugs at the same time. The front trailing plug didn't want to budge when I tried to remove it. Gave me that sick feeling like I was going to do some damage if I tried any harder to get it out. Not sure if I just had bad alignment with the plug socket or??
Might take it to the dealer or a local rotary shop and see if they have any better luck.
08-03-2010, 06:03 PM
#94
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08-20-2010, 10:45 AM
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I searched for it a lot and I could not find it, That's why I am asking you guys. Do you know if there is a DIY on removing the stock air box and that flexible thing that is attached to it. preferably with pictures? 
I want to do my coils but I don't know how to remove them.
I want to do my coils but I don't know how to remove them.
08-20-2010, 10:50 AM
#96
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-stock-air-filter-box-144789/
Not a full blown removal, but not too far from it.
08-20-2010, 11:19 AM
#97
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Thanks Jon, I've already seen that one and I can take the box out. I want to know if there is anything for complete removal of the box and flexible plastic part.
08-20-2010, 11:29 AM
#99
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If I loosen the accordion tube on both sides can I remove it without unplugging any vacuum hose? I just want to put that thing to the side so I can get to the coils.