| Hi Folks, I've been pulling my hair out trying to figure out why my Racelogic traction control, which used to work great on my '93 NA, causes my '95TT to throw Code 51 open injector circuit fault codes even after triple checking all the connections. I had to pull out the O-scope again to figure out what was going wrong and after some lengthy e-mail discussions with Racelogic here's what we've determined. It seems the later model ECUs come equipped with an early form of misfire detection that looks for the ringback in the injector wave signal. If it does not see this ringback, errors will be thrown up on the ECU. Below I compare a generic Racelogic ringback cartoon with the actual input and output O-scope results. You can see the ringback causes instantaneous voltages up to 290V whereas the Racelogic output contains no overshoot at all. (I thought that was a good thing) 
The solution to this problem seems to be to buy an additional coil pack below which mimics the ringback characteristics of the OEM system and install that in parallel with the injector wires. 
At least that's the theory. I'll find out if this really works or not after I receive and install the above coil. I'm putting this out here on General to give you guys with later model ECUs wanting to install the Racelogic traction control a heads-up. If you guys think this is worthy of a FAQ I'll re-write and add more details after I confirm this solution actually works, but otherwise folks can find the information in "search". Another motivation I had for putting this out here is I get the feeling that many folks think the ECU is simply another component like the MAF, CAS, O2 but it's not. The ECU is a lot more complicated and evolved which cause inconsistencies from one year to the next and from one model to the next. For example trying to reset the later 16-bit ECUs with a paper clip will not work as outlined in the FAQ. ConZult certainly doesn't work on all model ECUs where accessing the 16-bit ECUs is more finicky if not impossible. My '95 has a boost pressure sensor built in and apparently includes misfire detection logic which wasn't included in previous years. The knock sensor circuit is highly refined and very different between the NA and TT. The point is one ECU does not fit all applications where the differences are still mostly unknown 22+ years later. Despite this minor setback Racelogic tech support has been top notch! They were extremely prompt and responsive in getting to the bottom of this. This is one no nonsense vendor that's worth the extra money. Links to the main Racelogic traction control write-ups:
RLTC write-up on FAQ
RLTC write-up on Auto-FAQ
OverZealous (CT)
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Racelogic Traction Control ECU Code 51 Potential Solution - 
04:09:41 07/06/12
