I'm a bit OCD when it comes to wiring, I like everything to be neat and tidy. That means all wires bundled together, all connections soldered and heatshrinked. So every time I get a new car, I go through all the wiring to make sure everything was done right. Unfortunately, this is never the case...
While cleaning up the engine bay wiring, I found something really strange. Check out the photos below:
Had to do some intense detective work to figure this out. Turns out it's a 1.5kOhm resitor that is in series with the coolant temp sensor for the ECU. This temp sensor's function is tell the ECU when to use the cold map (rich fuel mixture), this resistor in series tricks the ECU into thinking that the engine is actually cold.
In parralel with the resitor is a thermoswitch which closes when temperature rises to a specific point (not sure what temp though), this then shorts out the resistor and everything is back to normal so the ECU now thinks that the engine is warm.
I believe whoever did this wanted the engine to run on the cold map for longer because of Mazda's stupid coolant routing desing. This design flaw causes the rear of the engine to be hotter then the front. Meaning that the coolant temp sensor at the rear of the engine is reading warm when the engine is actually still a bit cold.
Although the mod works, there is no reason to have it. After removing all that junk, the car runs normal and no longer runs rich. So confused why they did this.... so silly!
The thermoswitch used - http://www.ngt.co.jp/en/Type03.html
Also spent the weekend replacing all the hoses and flushing out the coolant. Pretty happy to brand new hoses in the engine bay =)
And just another sneak peak before the new wheels and tyres go on.
Taken while we were at MX-5 Plus.
We went by MX-5 Plus yesterday just to browse and I ended up buying a genuine Mazda shock tower brace (strut brace) and some horns to replace my stock ones. Instead of going with an after-market brace, Richard (owner of MX-5 Plus) recommended the factory option item as it actually works with the better mounting. Also found some klaxon TR99 horns which are rated at 110dB each, so my NA6 now has two of these instead of the tiny factory item.
Just a quick update today... Had all four guards rolled, so the inner lip is now flat. Work was done by FineFitment and I can definitely recommend them to anyone that needs some extra clearance for wheels.
Picked up my new car yesterday, a 1990 Mazda MX-5. It's Australian delivered and in pretty good condition. Won't be doing much to this car apart from wheels/fat tyres, also just some regular maintenance. Should be an awesome track car until I get my RX-7.
The car came with the following parts:
- HKS headers
- MX-5 Plus custom stainless steel exhaust system
- Garage Vary front lip
- Yellowspeed Racing coilovers
- Mazda hard top
I've also ordered Axis OG-San wheels from JDMYard, they were by far the cheapest I could find. Email response was fast and shipped out the next day. Definitely recommend them =) . The Axis OG-San wheels are replicas of the SSR Formula Mesh, which are the replicas of some BBS wheels. I ordered them in 15x8 +25 gold finish.
For tyres, I've again chosen to go for maximum rubber instead of the stretched look. But I also wanted to avoid getting semi-slicks or R-Compound tyres for a car that I will most likely drive on a daily basis. So I decided on the Hankook R-S3 in 225/45 R15. These were hard to source in Australia and they sell for $335AUD, compared to $110AUD from TireRack in the US. After shipping and other fees, the tyres cost me just under $200AUD each landed at my door. Total saving of $540!!
It's been nearly four months since any progress has been made on the MX-5 builds. Has been way too long... luckily Duy has picked up the NA8 half cut from MX-5 Plus.
The silver MX-5 will be converted back to a standard NA8 using this half cut. The black shell will be receiving the SR20DET and all the other JDM goodies =)
After visiting MX-5 Plus, we quickly rushed home to work on the MX-5. Was just mainly cleaning up all the interior, full degrease and hose down. You wouldn't believe how much crap is under the carpet...
Track build MX-5 next to the donor MX-5, the silver one currently has the SR20DET gear that will eventually end up in the black track build MX-5. Check out all the mess under the carpet...
We made our way to MX-5 Plus today, possibly the best Mazda place in Australia.
They've been in business for awhile but today was their official opening for Serive/Parts Warehouse. There were a few customer cars on display as well as some classics on show.