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I seem to keep loosing sparks on plug intermittently. Not always the same ones I am running a 20B with microtech and stock coils. You can tell when a plug drops out as the idle goes a bit rough.. I would say it seems to clear when you apply throttle but have not verified that with a timing light. i.e I am using a timing light to see if I have a signal on each plug lead in turn and assume no signal means no spark.
I am running the BR10EG plugs currently. Could it be with my rich idle around 11.2-11.8 AFR these are suffering and getting flooded out? from cold start is is probably more lie 10.8 AFR. Would I be better with a stock style Mazda plug? If I try and lean out much more that this I seem to get a stall issue when warm.. but that is a separate issue I am trying to get to the bottom of!
Trying to get to the bottom of why this is happening as it is very frustrating.
I seem to keep loosing sparks on plug intermittently. Not always the same ones I am running a 20B with microtech and stock coils. You can tell when a plug drops out as the idle goes a bit rough.. I would say it seems to clear when you apply throttle but have not verified that with a timing light. i.e I am using a timing light to see if I have a signal on each plug lead in turn and assume no signal means no spark.
I am running the BR10EG plugs currently. Could it be with my rich idle around 11.2-11.8 AFR these are suffering and getting flooded out? from cold start is is probably more lie 10.8 AFR. Would I be better with a stock style Mazda plug? If I try and lean out much more that this I seem to get a stall issue when warm.. but that is a separate issue I am trying to get to the bottom of!
Trying to get to the bottom of why this is happening as it is very frustrating.
Thank you
Lee
What are the condition of your plugs? i.e. what do they look like when you pull them out?
Black? Also wet?
Plugs are black and a bit wet yes! Now I put in new plugs and dried it out I got it fired up again. Idle is hunting at about 11.2 AFR from cold so I imagine rich. 11.2 or so when hot is just on the verge of hunting but much better. if I can get it down a click on the fuel table it should be fine but I seem to be right on a point of fine balance where it is okay sometimes and then something will happen and it goes to lean and dies. Just need to do some logging and see what is happening.
Mainly I want to know the best plugs to use in this situation that will be least prone to clogging and being a bit rich. I thought the BR10EG's were but maybe not?
Also I wanted to check there is nothing else that could cause the plugs to be dropping out sometimes. i.e an ECU glitch or something with the Microtech?
port on mine is a very minor exhaust port.. just a tidy up on the sleeves. Inlet ports are all stock.
Funny you mention that.. I wondered if premixing might be causing a problem.. So I am running without an OMP and have gone up from 150:1 fuel mix ratio to about 125:1 recently.. it doesn't really smoke which I was kind of using as a governor as to how much premix I could add. I was going to get to the point of smoke at idle and dial back. I have seen people recommend ratios from as much as 100:1 to around the 150:1 I started at.
Plugs are black and a bit wet yes! Now I put in new plugs and dried it out I got it fired up again. Idle is hunting at about 11.2 AFR from cold so I imagine rich. 11.2 or so when hot is just on the verge of hunting but much better. if I can get it down a click on the fuel table it should be fine but I seem to be right on a point of fine balance where it is okay sometimes and then something will happen and it goes to lean and dies. Just need to do some logging and see what is happening.
Mainly I want to know the best plugs to use in this situation that will be least prone to clogging and being a bit rich. I thought the BR10EG's were but maybe not?
Also I wanted to check there is nothing else that could cause the plugs to be dropping out sometimes. i.e an ECU glitch or something with the Microtech?
port on mine is a very minor exhaust port.. just a tidy up on the sleeves. Inlet ports are all stock.
I imagine you are not getting a lot of responses because most of this stuff has been covered. From my experience I usually give what the car sounds/feels best a healthy brap or a healthy idle while not being too stringent on a lean AFR. But not in the 11's, more like 12-13 if need be.
For the plugs these have been covered see this thread. Reading the spark plug will tell you about your tune conditions too. If you are pulling them out and they are wet then yeah, too much fuel, and if they are black with limited driving miles you are too rich.
I personally use the 7420's, and before that stock FD 9's. https://www.rx7club.com/single-turbo...range-1016900/
So progress report! I thinking I am making some. So first I checked the manual, all it says about lights is it will have the orange light on when ignition is on. Does not say about what status the ECU shows anywhere I could find, which is mainly what I want to know. Ignition on, status shows idle, changes to crank when you start to key over or touch the throttle and I noticed hen engine is running it says TPScal. Can someone confirm this is correct?
I checked injectors are wired correct which pretty sure I have done before and yes they are. Then I remembered the idle control valve has been connected to the aux output but never successfully setup. So I thought I will unplug it just in case it is doing something to mess with the idle. Anyway. Fired up and pulled fuel out during warmup as I knew was already rich. Possibly more to come put still. Then when warm I managed to pull lots out of the table more so than ever before. Some before and after shots below. Afr was hi 11's popping into 12's now and seems happy when fans cut in and out and stop starting. It remains to be seen if it will function the same when I next run up from cold. Will try tomorrow. If so I will gradually try and get more fuel out. I would imagine I will start getting close to the limits of the 875cc primaries before long though. We will see. Interesting though! Could well have been the idle valve causing trouble for all this while! We will see in due course!
So this is where I started and it usually wanted to be before rebuild and plug change yesterday. My idle cell is the 1000rpm 18Hg one.
This is where I have previously managed to get without starting to get a stall issue at some point.
This is where I am right now and it seemed like it was going to let me take even more out?
not sure if I can pop pull the cell that has 1.19 in down in line with the rest? I.e.0.81 or whatever is the next lowest value below the cell? Wasn't sure if it uses this cell for cranking? Also is it wise to have the cells below my idle cell a touch richer or the same value to help pull it back up if idle drops due to a load? I am not convinced it will be okay with this next time I try or after a decent drive but let's wait and see!
Here is my water map before and after too. I left it a bit on the rich side through warmup assuming I might take a bit out of the main map. As I took quite a lot out this might need to have some added back in but again I will have yo wait for another day.
I ran the car up again this evening. Was not quite cold but cool enough to work through most of the water table I adjusted. Had to put back I. A couple of % as expected but was about there. Then when I get to around 63deg water temp something happens that makes the idle fluctuate lean and die? This is what I have always struggled with trying to maintain a lean afr. So I messed about a bit watching where the map was going when it died and it basically drops into the idle row and even though that has the same cell value. ( I guess maybe not the cell to the right actually. That could be it. The idle is in 18Hg but I think pulling a bit less so partly into the RH cell. I may have answers one of my questions. Basically I seemed to get around it by adding a bit of fuel in the idle tow at 18Hg which seems backwards. But it appeared to work.
this is what I have now. Went for a drive and seemed fine. So leading onto me next question. The cell to the right and below my 1500rpm/18Hg idle cell jump quite a bit I'm value. This is just when you give a little throttle for a light rev. It stumbles if these are leaner. Should these be like this or should they be lower valued and pump settings used to increase fuel on throttle application. I ask because at points cruising you hit these cells and no surprise the AFR is rich in the 11's?
Also I my 24Hg column should the values generally be lower all the way down as again when you hit this on light throttle cruising AFR is in the low 11's and I am pretty sure it should be around 13-14? My AFR on light load and throttle seems pretty good around mid 13's. Some's lower spots but smooth. Of course as you can see from the table this is a pretty fresh work in progress. I have a tuner but want to learn and do for myself what I can!
Thanks for pointers.
Funny you mention that.. I wondered if premixing might be causing a problem.. So I am running without an OMP and have gone up from 150:1 fuel mix ratio to about 125:1 recently.. it doesn't really smoke which I was kind of using as a governor as to how much premix I could add. I was going to get to the point of smoke at idle and dial back. I have seen people recommend ratios from as much as 100:1 to around the 150:1 I started at.
Thoughts?
Sorry for the delay on this..
Yeah, I don't think running 125:1 would be the culprit, I know many people run similar ratios without any issues.
I just asked because, in the past, during a break-in with pretty hard seals I noticed fouling from premix. However, I was running ratios in the range of 42:1-64:1 to ensure that everything was well lubricated, so a bit extreme.
I would probably look towards factors other than your premix, unless you're using an oil that's unsuitable for premix applications.
Thanks for the reply.. Glad those oil ratios are okay as I am Being told on one hand to run 100:1 and another 150:1 hence I thought middle ground seemed like a good idea.
I think and hope the plug fouling is a combination of an oil filled new engine and very rich AFR's on idle and vacuum cruise. Was hitting mid 10 idle and mid to high 10's low load cruising in the 18-24hg region. I assume these should be 14-15 AFR and what is known as closed loop? I.e constant throttle and load? If so I need to work at pulling fuel out here. There are a couple of cells it hits on off idle to 2000rpm free rev that seem to demand extra fuel to stop it stuttering on the rev. You then hit these cells during cruise and it is way rich. Can I get over this extra fuel required as you come off idle using the pump settings? With the new plugs it has made a drastic improvement and allowed me to pull a lot of fuel at idle as the tables I posted show. Would.love some feedback on what I have so far.
cheers!
Thanks for the reply.. Glad those oil ratios are okay as I am Being told on one hand to run 100:1 and another 150:1 hence I thought middle ground seemed like a good idea.
I think and hope the plug fouling is a combination of an oil filled new engine and very rich AFR's on idle and vacuum cruise. Was hitting mid 10 idle and mid to high 10's low load cruising in the 18-24hg region. I assume these should be 14-15 AFR and what is known as closed loop? I.e constant throttle and load? If so I need to work at pulling fuel out here. There are a couple of cells it hits on off idle to 2000rpm free rev that seem to demand extra fuel to stop it stuttering on the rev. You then hit these cells during cruise and it is way rich. Can I get over this extra fuel required as you come off idle using the pump settings? With the new plugs it has made a drastic improvement and allowed me to pull a lot of fuel at idle as the tables I posted show. Would.love some feedback on what I have so far.
cheers!
As noted by another party in one of your other many threads, you are at the limit of Microtech. I've heard it elsewhere that tuning a microtech is like tuning a carb, there are no extra features, it is all fuel related tuning. Carb jets that work at WOT won't work at idle, etc. etc. Carb jets that are good for AFR, won't be good for WOT. They work for drag cars, but leave a lot to be desired.
Like I said, the manual is 30 pages with table of contents (a joke), from 1990. Super simple to get a car running, but not running great.
I also think you are at your limit with your own knowledge.
I'm no expert either but, closed loop tuning is where the ECU references the current AFR and adjusts fuel to get to your desired AFR. Microtech cannot do this.
Especially with a 20B, I think its best you look for a qualified tuner, and go with the ECU they are most comfortable with, before you make a costly mistake.
Thanks for the reply.. Saw closed loop referenced in a post by Aaron and made an assumption. Maybe not a Microtech specific post. I have a tuner to tune my Microtech. No problem there. I am just trying to learn more for myself as I go along which I think I have said before. Of course I am not going to risk my new 20b on my limited I'm knowledge! But you only learn by asking questions. And low load/idle is somewhere I am happy I can learn a bit more without risking my engine. If in doubt though I will just no more for when I next meet with my tuner. We are doing a bit at.a.time road mapping for now while I run in.. I.e. Mapping up to each rpm limit in tune for the next 50 or so miles.
Thank you for help along the way.
05-24-17, 06:54 AM
