CGLockRacer Dork
2/1/13 8:52 a.m.

I encountered a similar problem during the NJ Devil in the Dark 12 hr race in 2011. Turned out the MAF had a loose connection/was coming loose from the mounting. The car would shut down, studder, etc. Then be fine the next second. Might want to check there. It took 2 pit-stops to find the problem.

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Alan Cesar
Alan Cesar Dork
2/1/13 9:00 a.m.

The PBOC Motorsports Club had their big, annual bash a couple of weekends ago. They call it Winterfest, which is something that has to annoy those in America's chilly northern areas. It was a wonderful 80 degrees and breezy throughout the weekend, which was a great way to see and appreciate fast Porsches, BMWs and more taking fast laps around this historic airport track.

We took our humble little yellow Miata there, with a freshly installed six-point Schroth Racing harness got from HMS Motorsport. This car may be a low-buck racing effort, but our bodies aren't low-buck. We want to come home in once piece, whether the car does or not.

Things went really well, right up until they didn't. It wasn't a big off-course excursion, but rather the car's untold mysteries catching up to us. After about half an hour on track, the car would start having strange shutdown issues. For seconds at a time, it felt as though someone shut the ignition off, then turned it back on. Not a misfire, but a full-scale power loss. We changed as many parts as we could borrow from No Mo' Money Race Engineering with a little lighting and moral support from our paddock neighbors, the guys at IPG Parts.

Alas, we had no success in tracking down the problem, so we packed the car up early on Sunday and headed home a bit saddened that our Miata didn't run so well. Now we have a mystery to solve before the next event. These are the woes to expect when you awaken a sleeping toy car from a neglectful, six-year slumber underneath someone's tree.

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stylngle2003 New Reader
2/1/13 11:29 a.m.

2 things.

1: your roll cage doesn't pass the broomstick'd you get past tech with it like that?

2: our '91 is still having phantom shutdown issues too.
Thought it was fuel delivery-related, so I changed the filter, pulled the tank access cover and pump out, cleaned the sock filter, swapped in a known-good pump and scooped out 2 cups of rust/scale from the pump tray. A little better, but still not right (couldn't slalom at auto-x without it doing hiccuping/shuddering).
Checked and replaced the alternator belt and battery (battery was shot, belt was loose....thought it was a charging issue). No change. The maf connector is what I am going to try next...thanks CGLockRacer!

CGLockRacer Dork
2/1/13 8:32 p.m.

Basically with the car running, grab the MAF and shake it. The bracket broke on the SpecMiata we were running and when it would move around, the car would shut off.

mistanfo UltraDork
2/2/13 2:54 p.m.

You may also have some corroded connections where the alarm was installed. If it used a T harness for ignition interrupt, check the connections. I had to clean the spade connectors and applied dielectric grease on the last car that i removed an alarm from.

Hotmommaracing New Reader
2/3/13 10:41 p.m.

thought I was seeing things with that rollbar too. maybe the helmet is part of the rollover protection?

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