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Check Engine light after T56 Swap

Old 02-09-2019, 12:34 AM
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Check Engine light after T56 Swap

I've noticed that while I'm driving around my check engine light will come on. I don't have my VSS hooked up to anything, is that going to cause a problem or can I just ignore it untill I get the Dakota Converter?
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Old 02-09-2019, 07:44 AM
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Re: Check Engine light after T56 Swap

yes that will trip a code
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Old 02-09-2019, 02:17 PM
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Re: Check Engine light after T56 Swap

I'm aware of that, I was asking if the code is going to cause an issue with the rest of the car or can I just ignore it?
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Old 02-09-2019, 04:45 PM
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Re: Check Engine light after T56 Swap

Yes it will cause issues. It confuses the ECM because it has no clue how fast the car is going. The usual complaint it that it idles high and the RPMs hunt. It won't run right regardless of the details until it's all hooked up right and working.

If you have the original T-56 reluctor still in there, eeeeeeezyest thing to do is use the Dakota Digital ratio box. You need to set it up to convert 17 pulses per drive shaft rev from the T-56, to either the 2 pulses or 4 pulses (4 I think in your setup) per rev that the ECM needs.
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Old 02-09-2019, 04:56 PM
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Re: Check Engine light after T56 Swap

Originally Posted by sofakingdom View Post
Yes it will cause issues. It confuses the ECM because it has no clue how fast the car is going. The usual complaint it that it idles high and the RPMs hunt. It won't run right regardless of the details until it's all hooked up right and working.

If you have the original T-56 reluctor still in there, eeeeeeezyest thing to do is use the Dakota Digital ratio box. You need to set it up to convert 17 pulses per drive shaft rev from the T-56, to either the 2 pulses or 4 pulses (4 I think in your setup) per rev that the ECM needs.
Crazy, I followed Online's T56 swap thread and saw you on there a lot. The only reason I haven't put a Dakota on it yet was because I used all of my available swap money and I have to wait till the end of the month to get the converter. Could I just ignore this light for now or will it result in bad behavior from the car. I haven't noticed anything wrong with it, then again I've only been driving it for 2 days.

Thank you for your expertise.
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Old 02-10-2019, 09:19 AM
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Re: Check Engine light after T56 Swap

Yes I recall helping him out alot in that thread, he was very methodical and did his research well with good documentation. Made it easy to contribute usefully.

If whatever ill effects it has are acceptable to you, then sure, you can wait. It isn't a "do it or else you'll tear it up" kind of thing; more a matter of driveability. We all have our own thresholds of pain in that dept that we have to live with by ourselves.
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Old 02-10-2019, 05:10 PM
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Re: Check Engine light after T56 Swap

You will experience stalling and mild drivability problems. If you know how to drive, it won't kill you.
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Old 02-14-2019, 07:47 PM
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Re: Check Engine light after T56 Swap

Originally Posted by jmd View Post
You will experience stalling and mild drivability problems. If you know how to drive, it won't kill you.
I haven't noticed any issues other than the idle is a tad high once the light comes on. I have noticed my fuel economy has gone to crap however, now this could be because I drive a tad different or it could have something to do with the check engine light.
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Old 02-15-2019, 07:51 AM
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Re: Check Engine light after T56 Swap

Back in 2001, I did a T56 swap in a 91 Z. I did not have a VSS signal going to the ECM. I experienced stalling when pushing the clutch in while driving. The engine would hunt for an idle RPM and stall out. It was annoying and eventually caused me to hit something one day while trying to turn steer into a construction site from off the highway. I pushed the clutch to coast and brake and the car stalled. Lost power brakes and steering and ended up really jamming on the brake pedal. This locked up the wheels in the sand and I slid into a bulldozer. No joke. I put the stupid VSS setup in the following weekend AND replaced the bumper cover.
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