Flex fuel with the Haltech Pro Plug-In ecu
 

I've been running the fuel composition sensor on my car since early November. For those of you interested in running the fuel composition sensor with a Haltech Pro Plug-In ecu you will need the following:

Fuel composition sensor - GM part number 13577394
Harness for fuel composition sensor - GM part number 13352241
Haltech I/O expander box or a Zeitronix ethanol gauge

The fuel composition sensor and the harness can be ordered from any GM dealer. I ordered the parts from gmpartsdirect.com. The Haltech I/O expander box is needed because the pro plug-in ecu for the s2000 does not have a spare dpi needed to run the sensor. The sensor does not output a linear 0-5 volt signal. If you do not want to purchase the Haltech I/O expander box your other option is to purchase a Zeitronix ethanol gauge. The Zeitronix ethanol gauge can convert the signal to a linear 0-5 volt signal allowing you to use a spare avi.

The fuel composition sensor is also capable to reading fuel temperature. If you choose to run the Zeitronix ethanol gauge you would need to occupy another spare avi to read fuel temperature. Both are read when using the expansion box and a single dpi.

The installation is pretty straight forward. The sensor is mounted on the return line. I have my sensor mounted near the brake booster.

I chose to purchase the expansion box. This is what it looks like:

https://scontent-b-iad.xx.fbcdn.net/...12562758_n.jpg

Here are the sensor and harness from GM

https://scontent-a-iad.xx.fbcdn.net/...97301092_n.jpg

Here is a screen shot after installing the sensor. I was logging the stuff pertaining to the fuel composition sensor on the last row.

https://fbcdn-sphotos-h-a.akamaihd.n...84671034_o.jpg

Looks like a lot of data. What is goal with this gear? I read an article about fuel manufacturers upping ethanol from 10% to 15% to increase mpg goals. Article said it can cause premature wear on pre 2008 engines. Any thoughts?

The goal is to accurately compensate for any ethanol present in the gasoline. The sensor allows you to run any blend of gasoline and E85. It's good for those who live in areas where E85 is not readily available. Increasing the ethanol percentage in gasoline by five percent isn't going to do much. It should not cause any premature wear issues in the long run.

Great info for us FI Haltech users. Thanks!

Does the expander box plug right into the ecu?

Yes

Good thread, but can i ask why do you need the Harness for fuel composition sensor - GM part number 13352241 ?

it looks like if you just get the part number that starts with 135xxxxxx you get a pig tail to wire into your IO expander, correct ?