Pulse widths dropping to about half

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rally2
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Pulse widths dropping to about half

Post by rally2 »

I have been having a few issues with the MS hardware but I think I have them sorted.

I am running a V3.0 board MS2 with 2.88 code.

I have been seeing the pulse width drop when the engine is under load at certain RPM. At around 4500RPM to about 6000RPM I will see the pulse width drop from 4.x down to 2.x. The engine then goes completely lean.

I can't see anything in the setup that should cause this. Could it be a hardware issue still?

Here are the msq and log files.

http://www.rally2racing.com/MR2/datalog200805271747.xls

http://www.rally2racing.com/MR2/datalog200805271752.xls


http://www.rally2racing.com/MR2/resistorpack4.msq

You can see below the issue I am seeing. The car bucks wildly when the pulse width goes down and it runs real lean.

Image

Thanks,

Jeremy
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Philip Lochner
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Re: Pulse widths dropping to about half

Post by Philip Lochner »

One thing I can think of is check your DECEL settings on the AE page. It might be that something is triggering decel causing that reduction in PW.
Best regards
Philip
'74 Jensen Interceptor Mk3 (MS-2 EFI, GPIO + GM 4L60e)
'80 Jaguar XJS 5.3L V12* (MS-2 EFI + dual EDIS-6)
and about 10 others.
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rally2
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Re: Pulse widths dropping to about half

Post by rally2 »

I never see it go to decel on the log, but I do see crazy mdot and tpsdot numbers. I am using Xtau for enrichment. Would the tps based enrichment still be working with the Xtau enabled?
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Philip Lochner
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Re: Pulse widths dropping to about half

Post by Philip Lochner »

rally2 wrote: I am using Xtau for enrichment. Would the tps based enrichment still be working with the Xtau enabled?
Sorry, I can not answer that, I've played with xtau only very briefly.
Best regards
Philip
'74 Jensen Interceptor Mk3 (MS-2 EFI, GPIO + GM 4L60e)
'80 Jaguar XJS 5.3L V12* (MS-2 EFI + dual EDIS-6)
and about 10 others.
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preston
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Re: Pulse widths dropping to about half

Post by preston »

TPSdot (and MAPdot accel still works with X-Tau enabled).
Is it normally expected that you would stillh ave some TPS/Map AE when running Xtau ?

I thought Xtau kind of replaced map/tps AE.

What is your experience? Is some map/tps ae still needed even using xtau ?
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