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Old 07-31-2009, 09:54 PM   #1
Hittin' Boost & Cones
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Default Solve my stumble PLEASE.

Figured I would take time to research this while the motor is out of the car.

My car will get random jumps in the CAS signal, causing it to read 10,000 RPMS and suddenly blip the rev limiter, causing a lean burst and a major stumble. Luckly it almost never happens under boost, but i can not have this happening with a brand new engine. The lean spots are VERY severe (19:1).

Here are some logs. As you can see one didnt get a chance to activate the rev limiter, the other one did..causing my AFRS to spike way lean.

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I am running Hi res code, I dont think I ever had this issue before I upgraded the code, but I am not positive. I made the correct mod before I installed the code ( a capacitor I believe).

I am running MS1extra Hi res code in parallel. The car is a 1996 Turbo. My fuel map is pretty decent and the spark is only a slightly more aggressive version of the base map. Ask if you need more details.
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Old 08-01-2009, 09:24 PM   #2
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No ideas? Come on!!!
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Old 08-02-2009, 06:32 AM   #3
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I would inspect the CAS wiring, starting from the CAS itself, down to the mods on the board. Is it an MSPNP?

Jim
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Old 08-02-2009, 01:13 PM   #4
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Nope, I soldered it myself.

I'm going to pop open my megasquirt and go through all the mods to make sure its all good.
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