NB MX-5 Hey, it's Minnie!

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
After washing her the other day I noticed the front of the diffuser and my PPF brace were dirty. You may recall I spoke about how dirty she got at MATG, this underneath shot is an indication of that (this was after two times rinsing off the underneath):



In the morning before C&C I jacked her in the air to take care of that. I knew there was probably still some gravel trapped in the butterfly brace so decided to dig out whatever was there. To paraphrase Colin Chapman, I added lightness:



I didn't know where in the hell that piece of wood came from. PPF brace had some scratches now too, but it's otherwise all good.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Thanks. It's my pleasure. I don't have too much more before I'm all caught up to present day.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Since I was finally going to do an autocross I decided to put the driver's Recaro back in for that. Also figured I would install the larger JR front sway I have to see what that did for my handling. Picked those up from storage and went about putting them in. In the process found the underneath of the car in front had a lot of mud spray (go figure). While I had the undertray off I washed it up.

Seat went in ok, I had an extra seat belt receiver lying around so I put that on the seat to keep me from having to swap it around. Hoisted her up in the air, removed said undertray and went about pulling the sway bar. Got it out and the bigger one in with just a few hiccups. Had some issues with the bushing brackets lining up so I pulled it back out and turned it 180 degrees. Finally got the bolts in along with the braces. Checked to make sure my end links were even and the bar was level, then put the undertray back on.

The mail lady brought my new COPs during this work. I thought I might as well suck it up and buy some brand new ones to see if that corrected some of the minor problems I had been seeing. Some research showed Denso coils available on both Rock Auto and Amazon. I ended up going with Amazon because they were a little cheaper overall with free Prime shipping. FYI, the new number for these is 673-1300. I put each one in place and marked the sides to clearance so they wouldn't contact the valve cover. Used a sanding drum on my Dremel to take care of that. The coils came with some rubber gaskets so I decided to give those a try and see if they keep the plug wells dry. Buttoned up everything and she fired right up. I also changed out the air filter for a slightly smaller one I had lying around, I was using it originally but changed it for the bigger one when I was trying to figure out what was causing my fuel dump under boost.

After all that I couldn’t get out for a test drive that day. We were having rain of biblical proportions so that would have to wait.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Autocrossed her. Had a lot of things to post, and some videos once I remembered my YouTube login and I recovered from being in the sun all day. It was a blast, here are a couple of pictures to tide folks over.



 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Woke up the next morning feeling like someone beat me with a baseball bat. Not going to get into everything just yet, I did manage to get onto my YouTube channel so here are the promised videos:



Course was bumpier than I expected. There were a lot of minimal height changes which weren't bad, but they were exacerbated by pavement cracks so you might be set for a corner and then get bumped by one of those. First run was a 56.925. The next two saw me improve about 0.4 seconds over the previous time. Run 4 saw me improve by 1.2 seconds over the previous, and run 5 saw me improve 1.6 seconds over the previous (final run was a 53.397). Most of my time was made up in the slalom on the back side of the course where I kept my foot in it longer.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Hadn't done too much since the autocross. I did reconnect the rear sway, while there I noticed the muffler had been moving around enough to contact the diffuser so Iwould have to clearance it a bit more. I had also been having issues with the left front wheel contacting the fender liner under short/sharp deflections. A quick finger comparison with the right side showed I had less clearance there so when I put her in the air to swap the front sways I would get that fixed. I had also swapped the driver's seats around so I was back to the NB2 stocker.

Thoughts on the autocross. The bumpiness I mentioned made it difficult for me to get up to speed initially. My two years' layoff showed in my first run where I was off-line in a few places and got caught out. They had two traps set up so the course was divided and you could see where you were making/losing time. My first section times were pretty consistent and looking back I didn't see where I could have made up any time there. Second section is where I made up the time, mostly in the slalom section where I kept my foot in it longer. Don't know if I could have really done a lot better than my final run without other changes to the car.

Brown Santa made me a happy man. Managed to score a rare part, purely by chance when I was doing a search and came across someone on another forum who had spoken about having one and wanting to sell it. I got in touch, he still had it and the deal was done. Now I just have to get the screws needed to install it and then test it out.

 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Had some free time to myself so jumped into things. I opened the sealed bag my trap timer was in and found that someone had it out in the open previously. This was a good thing though as the mounting bracket had been modified so it would fit a Momo wheel:



I ran to Ace to get some appropriate fasteners then proceeded to get it installed. First, the mount:



You put four screws in to hold the wheel first, then the last two (seen) are what hold the mount in place. After that the trap timer goes on bottom first on that lip you can see sticking out. There is a small Allen screw that goes into the hole at the top, and that is all there is to it.



I needed to break out my teeny-tiny jeweler's screwdrivers in order to install the battery, and then I could try to figure out how to operate it. One thing to note, with the timer in place the horn button is very recessed so it can't be operated as you normally would.

Once that was done I pulled the front undertray and swapped back to my MSM front sway. The big JR sway I used for autocross showed signs of side-to-side movement with one of the bushings getting split. I wouldn't be putting that back in. I took measurements of both front shocks, both the overall length and the preload on the springs. Both measurements were the same, so something else was going on there. I would get some good measurements with her on the ground and then adjust the length of the driver's side to match the passenger side.

Finally although I didn't address it at that time, here is the rubbing the exhaust is doing on the rear diffuser:



Not horrible, but I would have to clearance it some more.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
I installed the battery in the timer. Remember I said there were teeny-tiny screws? See at the right side of the rectangular cover for those.



Turned out it uses two LR44 batteries, the other one was already in place. Popped the second one in and she booted up to this screen:



Those with keen eyesight will notice it was set for January 01, 1996. I left it like that while I ran some errands. Later I sat down to see if I could figure out how to get it set. As it turned out, it wasn't that difficult. First of all, there are four modes: Stopwatch, Alarm, Time and Countdown. The "Mode" button scrolls between those screens. I put it in Time mode and then pushed buttons to see what happened. Once in the Mode desired, pushing the Recall button starts numbers flashing. In this case the seconds were flashing first. If you push Reset the seconds go to zero. Pushing Lap changes to the next value for setting, in this case minutes. Using Reset will change that number. Continuing in this manner for the hour, date, month, year and day everything was changed to reflect current time. Honestly the only thing that was different from what I expected was the reversing of the Reset and Lap buttons to make changes (from what I normally see with other electronics). Now I had the date and time right in front of me. The stopwatch and countdown timer work as you would expect them to. Start the counting by pushing Lap. Pushing Lap again will give you a stop reading while the main timer keeps counting. Pushing Reset once will stop the timer, pushing it again resets the numbers. Not too sure about the need for an alarm though as I was not planning on sleeping in her any time soon.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Measured the height of the front coilovers and compared them side-to-side. Turned out they were only a couple of mms different. That got me to thinking and after I hoisted her ass into the air I checked the recommended spring length on the installation instructions against actual. Turned out both sides were off by 5-7 mm. I made those adjustments to bring them into the correct length. All of the nuts were tight so I didn't think anything moved, I must have just done them wrong the last time I messed with them. I double-checked the length of the rear springs but both were correct.

Then it was on to the main event. I took a good look at the muffler and found the driver's side was hanging lower than the passenger side, which allowed it to contact the lower diffuser. Note that NB1s have four hangers for the muffler, while NB2s only have three. The FM muffler I have only has three mounting points. I used urethane hangers thinking that would provide enough support, but with the extra piping of the dual outlet muffler the weight overcomes the lone hanger on the driver's side. I found that the piping had been resting on the 949 subframe brace I have in the rear (this is the piece I had previously relieved for some clearance). You can see the height difference here:



After some research I found this lovely little number:



Since I didn't have access to a welder, this seemed like it would do what I needed. This is where it needed to go:



For easier access I removed the lower diffuser. Figured I would be able to get it cleaner while it was off, and it was a good thing I did as I was still carrying some extra weight around from MATG:





After some playing with the hanger and removing the excess material, here was what I ended up with:



Final comparison shot to see how the muffler was even side-to-side now:



Test drive showed I was no longer rubbing on the front driver's side fender liner, and I had less vibration being transmitted into the car. I had noticed what I thought was more vibration when I first got her all back together in May, but thought maybe because it had been so long since I last drove her I had forgotten the normal level of vibration. I was now pretty sure that was due to the exhaust sitting on the subframe brace.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Had a little break while I went for some work-related training. I passed the eighth anniversary of my buying her, there had been a lot of changes over that time.

While I was gone I was thinking about the unusual and intermittent issue I had been having with stumbling after the car has been running for a bit. This was showing with the AFR gauge swinging up and down. One thing I came across is the fuel pump relay tends to fail gradually and causes the sort of problem I had been seeing. Since they aren't that expensive I went ahead and ordered one so it was waiting when I got home. Went out to install that sucker, and in the process found out what everyone was bitching about with changing it.

First of all, it is mounted on a bracket underneath the dash (just inboard of the steering column) with four other relays. After fighting it for a bit and not being able to get the relay to come off the bracket I decided to just pull the bracket. One (hidden) 10mm nut later and with all the wire connectors removed I had it in my hand. The problem with the fuel pump relay (and only that one in this group) is the raised nub that locks into a hole in the mounting tab, seen here:



You can't really see it but the nub is beveled to make it easier to insert, however the high part of the nub interferes with easy removal. My solution was to use a couple of jeweler's screwdrivers to lift the metal bracket enough to provide clearance for the nub to get the damn thing off:



Once the old one is off the new one slides right on. Then it's just put the bracket back in place and get the nut on (my work experience with working blind helped a lot with that), then reconnect all the relays. It had been raining here and I had done a lot of driving lately so I waited for the next day for a test drive to see if that would fix the problem.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Unfortunately the fuel pump relay didn't solve my shuddering problem. The rain finally let up and I drove her over two days for some errands. It didn't seem as bad as it had been when it did occur (wishful thinking?) but it was still there.

I washed her and then went to run some errands. As I pulled out of the garage I heard an unusual noise that was kind of an intermittent ping, like something was turning on and off. Pulled back in and popped the hood, what I saw was the supercharger belt moving on and off the pulley corresponding with the noise. So shut that sucker down and drove the wife's car instead.

When I got home I poked around and found the 'charger belt was rubbing on the power steering pump pulley along its bottom edge. Easily resolved by loosening the 'charger mounting bolts and moving it back forward where it belongs (around 1/8"). What was puzzling was that all the bolts were tight, so how did the damn thing move? Just got back from a test drive and all was well. For then at least...
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Think I mentioned the driver's inner fender liner getting damaged when I had the issue with the front suspension. Since that sort of thing bothers me I ordered a new one. Got that in the previous week so installed it. Here is the damage I am talking about (look about the middle of the picture):



Notice the three holes at the top of the picture. Getting to those is the hardest part of the whole replacement unless you want to take the whole front end off.



This is the area I am talking about where those three fasteners go:



I am used to working by feel but know that not everyone is comfortable doing that. If you have a very small head you can get in there to see to line up the holes, otherwise you will have to remove more than I did. If that's the case do it, so you don't get frustrated or break something else.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Headed for my first car show. I washed her the day before with Dawn to remove the old wax, next day after some errands I applied Zymol cleaner wax I have had for a while to see how it looked. Here was the result:





She would be in the sun the following day so we would see how shiny she was. Passing rain squall squashed doing that that day.

After eight years of ownership I finally got around to replacing a screw that was missing off the front of the passenger side side skirt. I could never find it on the Mazda drawings I have access to. Lo and behold while surfing eBay I found it. Was at the dealer that morning and they had some, so that is done.



Also while surfing eBay I came across a complete intake assembly for a '99-00 (from airbox to crossover tube) that was pristine. It was apparently removed when the car was new and set aside. No idea if I would ever need it, but given the hoops I had to jump through when the 'charger ingested a bearing I thought it would be nice to have. For less than $100 shipped it was mine now.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
Picked this up:



Outside picture at the show:



I feel like the Zymol gave the paint a richer color than my usual carnauba paste wax.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
I continued with research to try and figure out what was causing my stumbling issue. The morning of the car show it was the worst it had ever been, I thought she was going to die. As it turns out, a failing coolant temperature sensor can cause this. In looking at a data log I took I noticed the coolant temperature was fluctuating during the same time as the AFR swings. Since none of the ignition stuff I tried worked I figured why not? Ordered a new one up on Monday and picked it up on Wednesday. After looking everything over and checking the wires that I extended for the sensor connector I thought it would be a good idea to use some heat insulation on the wiring at the back of the engine. Ordered that from Amazon and it showed up. Went about installing it all once I had it in hand.

In order to ease access to the sensor I removed the shock brace, wiper cowl and brake booster hard line. That opened it all up.



Once I had the sensor free I went about removing the gasket off it. This was not successful, so I went to Ace to see what I could find. Ended up with a neoprene rubber washer that I cut down to fit. Next I cut a piece of the insulation tube to slide over the wiring for the sensor. It was much larger than needed just so I could slide it over the connector, so I folded it over and zip tied it up.



For the rest of the wiring in that area (ignition coils) I went with a split blanket that Velcroed together, as so:





Here was the finished product:



Since the fix I had not had any other problems with stumbling. I was curious about the gasket for the sensor though. The parts listing for engine relays on Mazda Motorsports' site does not have a diagram so no way of knowing what is what. The factory repair manual doesn't show anything either. I stopped by the dealer to see if their diagrams would show anything and they did. There were a couple of those on order then so I would be installing one upon receipt.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
I picked up the gaskets from the dealer that Saturday. They are these:



You can see they are using aluminum now, just like oil drain plug gaskets. The recess on the thermostat housing for the reroute I have is a little smaller on the OD than the factory one so I used a sanding wheel on my Dremel to pare the gasket down to size. After a drive I checked and it was leaking a little so I would try making it a little smaller. If that didn't cut it I would go back to the neoprene gasket I was using.

Forgot but the other day when changing wheels over I went to adjust the muffler hanger I had installed to shift things more to the right. Turned out one of the nuts had come off the U-bolt. I had one the same size lying around so put that on, but I thought I would get some Nyloc nuts from Ace to keep it from happening again.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
After sanding the OD of the factory washer down some more it was still leaking, so I put the neoprene one back in. Swung by Harbor Freight and got their copper washer assortment. Compared measurements between the 7/16" copper washer and the factory aluminum one, the only difference was the copper one was 0.09mm thicker. After looking at the sensor itself and how it fits into the thermostat housing I had, it appeared as though the sensor was bottoming on the housing before it was completely seated. The way around this was to relieve the outer edge of the sensor. I tried a couple of methods (file, Dremel metal file and sanding disc), the sanding disc worked the best. Note I tested this on the old sensor so I didn't screw up the new one. After some work I ended up with this:



Here are the HF copper washers:



Cost was around $7.00 and now I had lots of those suckers for other uses. Sensor was back in place, weather sucks right then here so a test would have to wait.
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
It was a while since my last post (about three months). Test drive went well. A few days later when I was driving to C&C on the freeway it started losing power. Pulled over to the side and she died. Sat for a minute than restarted her. The CEL was on steady but everything else was fine. Drove her back home and then began looking at anything to see if I could figure it out. Nothing presented to decided to do some datalogging. Got that all set up, on the way up my street the revs went to around 3500 and wouldn't come down. Back home it was. I was pretty disappointed in this development so she sat. I finally got my finger out a week ago and sent my log to Reverant to see if he could see anything, was still waiting to hear back from him on that. I did try driving her the other day, the CEL was on but all else was fine. That is, right up until the power fell off and she died. Wouldn't restart, acted like the battery was dead so I had to get a jump and drove her home. She started right up a day or so later. At that point I was leaning towards something wrong with the battery or alternator, or maybe an iffy ground.

About that time I received these pretty things:



I ordered them the previous week so shipping was very quick. Installation would have to wait for a few months as I was headed to work. Same with troubleshooting the engine problem. Should be warmer then at least.

If the tophats didn't do anything for me I would be visiting a certain someone who recommended them and dropping some more trees on his house...(that’s a joke BTW).
 

chiefmg

MOTM July 2015
:
'81 RX-7 GS, '00 Miata SE, '16 Camaro (wife's), '15 CX-5 GT AWD
I bought a new Supermiata QMAX reroute kit from someone I know who didn't use it. All I planned on using was the thermostat housing (I checked but 949 won't sell individual parts from the kit). The one I bought works fine but since I installed a new sensor and the gasket on it fell apart, I had been having trouble getting a good seal. If you check back in here you can see what I had done to try to make it work. The QMAX is configured so the sensor fits nicely with plenty of room for a factory gasket. One less thing to worry about for the future.
 
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