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-   -   Car is bucking, maybe bad CAS? (https://www.miataturbo.net/engine-performance-56/car-bucking-maybe-bad-cas-100678/)

1RMDave Jul 18, 2019 08:15 AM

Car is bucking, maybe bad CAS?
 
For about a week now my car has been intermittently dying for a split second and coming back, the tach drops instantly and then power comes back and tach returns to normal. It happens quickly and causes the car to buck. I noticed my megasquirt is logging a sync loss every time it happens, which was over 250 times in 30 minutes of driving this morning. Also strange is that my idle goes way up after the sync loss, almost like a cold start idle then drops to normal if I blip the throttle. I've checked and cleaned all the grounds and checked the wiring to the CAS, no changes. Has anyone experienced this with a CAS going bad? Should I dissect the wiring harness? Maybe something bad has happened in my ecu? Car was running great for a month before this happened. It has been really hot here and this problem started after an extremely hot day but it does it even when it's cool. Megasquirt gives my a sync loss reason of 39. Any advice? I'm trying to find a CAS locally that I can try/buy.

2manyhobyz Jul 18, 2019 12:04 PM

What year car is it?

1RMDave Jul 18, 2019 12:07 PM


Originally Posted by 2manyhobyz (Post 1542535)
What year car is it?

1994 with d585 lsx coils

codrus Jul 18, 2019 01:05 PM

Check your grounds again. Does the NA have the same electronics group at the front of the intake manifold that the NB does? If so, that one in particular.

--Ian

1RMDave Jul 18, 2019 01:06 PM


Originally Posted by codrus (Post 1542539)
Check your grounds again. Does the NA have the same electronics group at the front of the intake manifold that the NB does? If so, that one in particular.

--Ian

It does... I checked that one and sanded it already.

1RMDave Jul 18, 2019 01:19 PM

I may have found the problem, there were 2 exposed wires for the CAS in the loom from a previous repair (heat shrink split). I'll post when I know if it's fixed.


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