watchknut

It looks like we are making process on the SA22. Giving an update in case any one else runs into similar challenges.

About a month ago, my car died on the way home...just shut off. A jump pack got it started, but the tow truck driver said the the alternator was toast. I had it towed to a shop and they installed a new alternator, but said that when the car was running, they could not get a reading on their meter - it threw an error code.

I went and picked it up and it ran fine (or so I thought). The next week I took over to a friends house to have a look. He noticed a wire in the main loom that had melted over time - the red and white. We disconnected and cleaned the connection, wrapped the connection, and reconnected. Boom...the 15a fuse for the fuel pump popped. Was there a short in the fuel pump? We tested it and no shorts coming from the fuel pump or anywhere from the dash back. So we started unhooking and test for shorts in the engine bay. Nothing, there was still a short at the 15a fuse.

When inspecting the MSD coils, we noticed that the o connector was literally fused to the post and one of the other connector has partially melted. That didn't seem right, so I replaced the coils. The wiring in the car didn't seem to match the diagram we were using, so looked the Fox diagram and saw that the polarity had been reversed on the coils!!!

I have no clue how long this was like this, but it had been like it for awhile.

The car fired up and quickly noticed some key differences:

• The car didn't get bogged down at cold idle, before I had to constantly give it gas to keep it running and get warmed up
• The timing was off due to weak spark and the engine was only burning a small percentage of the fuel, causing the excess down the exhaust - super stinky and awful gas mileage
• The car now pulls effortlessly to near redline in every gear - it is so much more responsive and quick
• Dramatically improved gas mileage and little smell
• Need to get new plugs
• Need to adjust carbs, it is running too rich and too high an idle at 1250-1500rpm

I took to NAPA today and they tested the battery - full charge and 12.9v with the car off and 13.9-14.2v with the car running, so it looks like it is good to go.

I am shocked at how well the car drives now...and it will only get better. Hard to believe I thought it was running well before

Thanks to the advice from all of those on here!

7aull

iTrader: (2)

nice.catch.
!!
thank for sharing, glad you solved the Gremlin. ugh.

Stu A
80GS
AZ

mazdaverx713b

iTrader: (91)

That's great news! Nice find in the coil wiring really. We all take for granted when diag osing things, that the wiring is in the correct locations that it's supposed to be in.

watchknut

Members of the forum were incredibly generous with their time, and through their efforts, gave me a new confidence in working on these great cars.

LongDuck

The obvious next question is; which Coil was wired incorrectly - the front one (Trailing) or the rear one (Leading)?

I'm going to guess it was the rear mounted one, as that's the Leading Coil and would be responsible for providing the most spark, at the right time, and you described having power and idle problems. The Trailing Coil is there primarily for fuel efficiency and fires AFTER the Leading Sparkplugs, which is significantly behind the curve for spark advance. That you mentioned the car would barely idle is surprising, as your Distributor Advance may have been set way forward to even get it to idle at all. Most cars won't run on Trailing spark, only - at least not for very long. Once the engine gets up to a higher RPM, the spark advance curve is overcome by the velocity of the rotor face crossing the plug holes, and the engine will at least run acceptably on just the Trailing Coil and Sparkplugs.

You might want to recheck your timing based off of your #1 (front) rotor's Leading (bottom) spark plug wire and see where it sits today. If the PO half-assed the MSD ignition and coil wiring, what's to say he didn't monkey with the timing to get it to run at all...?

Overly advanced ignition can cause problems with detonation that break up Apex Seals in short order. Hopefully, yours is set within spec by the timing marks on the Front Pulley, but best to check with a timing light.

t_g_farrell

iTrader: (1)

Detonation on a rotary is only dangerous if boosted, otherwise its annoying at best.

watchknut

I’ll check timing. Both were wired incorrectly.

It would idle fine before, but only when warmed up.

In 1st snd 2nd gear at higher rpm it wouldn’t be smooth.

Now it fires right up, idles much better, and pulls strong through all gears at all rpm ranges.