Recent Posts

Spark Plugs and Plug Wire Replacement

One of the relatively easy improvements to your engine’s performance besides an oil change is to replace the spark plugs and the plug wires which is what I did today.

The recommended spark plugs for the NB Miata are the NGK Iridium IX plugs as seen in Figure 1. I also decided to replace the plug wires with NGK blue plug wires, both of which I purchased from Rockauto.com.

For the 1999 NB Miata, which has a 4-cylinder engine we need 4 spark plugs (Figure 2).

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Cleaning the Headlights

The Miata’s headlights were not as clear as I liked, so I decided to try to clean them with Meguiar’s headlight restoration kit (Figure 1), which I purchased at my local auto parts store.

Chris Fix has a video (and another) on how to clean up the headlights but I did not follow his method, and instead bought a restoration kit to see if it did the job. I think it did a decent job.

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Oil Change in the Briggs And Stratton Engine

Before I fix the ignition problem on the Briggs and Stratton engine that I bought on a whim the other day, I needed to complete an oil change.

I looked at the Operating and Maintenance manual and it said I needed to use 590 mL of SAE 30 weight oil which I bought at my local auto parts store for about $7.

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ECU Reverse Engineering Step 1 - Another ECU

As I mentioned in the previous post, I had been sent the 1995 ECU BPL9-18-881B by an online seller, so I ended up buying an ECU from a 1999 NB Miata with the model number BP5R-18-881. This ECU came in today, so I quickly opened it up to take some pictures and find datasheets.

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ECU Reverse Engineering Step 1

Going down the rabbit hole towards understanding the ECU, that I had had bought a few days ago, led me to realize based on ECU model numbers that BPL9-18-881B is the ECU for a 1995 Miata rather than a 1999 (Miata.net forum reference). I was disappointed and reached out to the seller on Facebook who did say they will send me the 1999 version and it was an error on their part, but so far they have not fixed their error. I consider this a loss of $60. I decided to move on, however. I bought a 1999 ECU on eBay and it should arrive in a week or so. Meanwhile, I will continue with this 1995 ECU since it will be cool to build two test benches to understand the difference between the cars.

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