OP
OP
iamdub
Full Access Member
Y'ain't wrong!
Growing up doesn't have to suck
- Thread starter iamdub
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Y'ain't wrong!
OP
OP
iamdub
Full Access Member
Ethanol sensor, plug with pigtail and fuel hose ordered.
OP
OP
iamdub
Full Access Member
Ethanol sensor and plug/pigtail delivered yesterday. I'm pleased to see that the sensor is as straight-through as it looks. In my researching, I read where it does pose a small restriction and people cobble together a bypass using multiple Y-splitters and other fittings to allow the fuel to simultaneously go through and around the sensor. I then found that it's only a concern in a high HP setup, like well into the 4-digit territory, where the small reduction in flow could be a factor. So, I'm good by a long shot.
Continental brand sensor. I think the more popular version, #13577429, is visually identical but can measure fuel temperature. Really not a concern for me so I saved the ~$13:
It appears that the $7.59 plug/pigtail branded "Hoypeyfiy" is a Delphi piece:
The flex hose has an ETA of 4/24 - 4/27. Currently digging through wiring diagrams to see if and how I can repurpose that VLOM circuit. Making a bracket to snap this sensor in to looks to be pretty straightforward.
Continental brand sensor. I think the more popular version, #13577429, is visually identical but can measure fuel temperature. Really not a concern for me so I saved the ~$13:
It appears that the $7.59 plug/pigtail branded "Hoypeyfiy" is a Delphi piece:
The flex hose has an ETA of 4/24 - 4/27. Currently digging through wiring diagrams to see if and how I can repurpose that VLOM circuit. Making a bracket to snap this sensor in to looks to be pretty straightforward.
Last edited:
OP
OP
iamdub
Full Access Member
Here's the VLOM plug I capped off by removing the connector from the VLOM and wrapping it up with electrical tape to keep the connector sealed in case there was power on any of the pins:
There's no way in hell I'm gonna cut that connector off and do any soldering back there underneath the cowl. I even considered removing the intake manifold. Just for a second, though.
I took note of the wire colors and looked up the E38 PCM pinouts on a GM upfitter site. I verified the circuits with a DVOM and even found that the pink was a switched 12V+, meaning I only needed to make up the ground and signal circuits:
The ethanol sensor signal output needs to go to an unused slot (#40) in the J1 plug. All the VLOM solenoid control circuits are in the J2 plug. The pins have to come out the front of the plug so the wires will need to be cut to pull the pin and wire through the front. I chose to use two wires that were next to each other in the plug, one for the sensor signal and one for the ground. I cut the wire and pulled the pin and length of wire out through the front of the plug:
I pulled the cut wire back up to where the harness splits to go to each PCM plug and rerouted it towards the J1 plug. I popped out the blockoff in the #40 slot and slid the piece of wire with the pin on it into position:
Here, I'm holding the J2 connector and you can see the rerouted gray wire in the J1 harness, aligned with the rest of it that I'll solder together:
There's no way in hell I'm gonna cut that connector off and do any soldering back there underneath the cowl. I even considered removing the intake manifold. Just for a second, though.
I took note of the wire colors and looked up the E38 PCM pinouts on a GM upfitter site. I verified the circuits with a DVOM and even found that the pink was a switched 12V+, meaning I only needed to make up the ground and signal circuits:
The ethanol sensor signal output needs to go to an unused slot (#40) in the J1 plug. All the VLOM solenoid control circuits are in the J2 plug. The pins have to come out the front of the plug so the wires will need to be cut to pull the pin and wire through the front. I chose to use two wires that were next to each other in the plug, one for the sensor signal and one for the ground. I cut the wire and pulled the pin and length of wire out through the front of the plug:
I pulled the cut wire back up to where the harness splits to go to each PCM plug and rerouted it towards the J1 plug. I popped out the blockoff in the #40 slot and slid the piece of wire with the pin on it into position:
Here, I'm holding the J2 connector and you can see the rerouted gray wire in the J1 harness, aligned with the rest of it that I'll solder together:
OP
OP
iamdub
Full Access Member
The unused slots in the plugs are blocked off to keep them weathertight. To maintain this, I squirted a little hot glue into the two empty slots from where I pulled the two circuits. This is why I used two that were next to each other. They were for the VLOM solenoids for cylinders #3 and #1:
To avoid cutting and soldering under the cowl, I repurposed the VLOM connector I was previously using as a weathertight plug as the other end of an adapter harness for the ethanol sensor. Here's the sensor pigtail/plug circuits soldered to the three repurposed terminals on the VLOM connector:
I put the PCM harness back together as it was before. I had just enough scraps of conduit to replace the crispy stuff that fell off during the operation:
Used some epoxy to seal up the holes in the repurposed VLOM connector to make it weathertight. The wires in the sensor plug are already sealed where they go into the plug:
I'm at a standstill until that double female flex hose is delivered. I can't even work on the mounting bracket since I'm unsure of the placement due to the hose routing. Of course, NOW that I've ordered other stuff, I find that there's a really short factory hose that would've been super clean. There are two versions and part numbers for it: #20967836, superseded by #85117207. I think it just got some trivial design update, like a piece of corrugated conduit added, and either are fine. Either appear to be out of stock in most places. The places that say it's in stock are the ones that take your money THEN tell you it's actually backordered and make you jump through hoops and wait a while to get your refund. EBay seems to be the best option.
#20967836:
#85117207:
To avoid cutting and soldering under the cowl, I repurposed the VLOM connector I was previously using as a weathertight plug as the other end of an adapter harness for the ethanol sensor. Here's the sensor pigtail/plug circuits soldered to the three repurposed terminals on the VLOM connector:
I put the PCM harness back together as it was before. I had just enough scraps of conduit to replace the crispy stuff that fell off during the operation:
Used some epoxy to seal up the holes in the repurposed VLOM connector to make it weathertight. The wires in the sensor plug are already sealed where they go into the plug:
I'm at a standstill until that double female flex hose is delivered. I can't even work on the mounting bracket since I'm unsure of the placement due to the hose routing. Of course, NOW that I've ordered other stuff, I find that there's a really short factory hose that would've been super clean. There are two versions and part numbers for it: #20967836, superseded by #85117207. I think it just got some trivial design update, like a piece of corrugated conduit added, and either are fine. Either appear to be out of stock in most places. The places that say it's in stock are the ones that take your money THEN tell you it's actually backordered and make you jump through hoops and wait a while to get your refund. EBay seems to be the best option.
#20967836:
#85117207:
Last edited:
swathdiver
Full Access Member
When can I drive over and get mine done?
OP
OP
iamdub
Full Access Member
You plan on being up this way? Or I can come to you! I wanna visit my grandparents this summer. Perhaps we can have that Florida TYF meet-up on @Dantheman1540's compound.
pwtr02ss
Full Access Member
X2! Awesome work man. Thanks so much for the detailed (VERY detailed) information! If I'm understanding all of this correctly, this will replace what the truck sees as alcohol content,
Correct? My ***** reading all sorts of crazy. Second full tank of 100% and it went from 14ish to 20% lol.
OP
OP
iamdub
Full Access Member
Thank ya! You know if I didn't thoroughly document my oddball methods of doing things, I'd have to explain them multiple times elsewhere!
Correct. Currently, it uses the O2 sensors (and other stuff, I'm sure) to calculate the alcohol content. Mine is always calculating it 20% or more low. I recently found that the O2 sensors I put in it 20K miles ago MIGHT be the wrong ones for it. They seem to be perfectly fine in all other fueling and emissions aspects. I could've bought new sensors at a cost of $100+ and HOPED that would fix my alcohol content inaccuracies. But I found that I could convert to the physical sensor, that should be accurate, for about the same cost. I originally shied away from converting because the pre-fabbed kits were ~$300 and had numerous fuel line joints and tapped into the coil pack harness for power and ground, none of which I was a fan of. Aside from enabling the physical sensor in the tune, the necessary parts are the sensor (~$55), harness (~$8) and a double female flex hose (~$30). So, under $100 before tax and shipping. It's HOW I'm doing mine that is so involved. But it's just cuz I wanted it to be like it came from the factory with the sensor in that location and corresponding plug in the harness.
BTW, I was scanning the Tahoe Twin the other night and his alcohol content was showing 0%. He always fills up at regular stations that have upwards of E10 and are never 0%. So, I'd say his is calculating low, by at least 10%. It's not gonna show less than 0%.
swathdiver
Full Access Member
Any option would be great! One of our kids lives in Tampa, the USS Kidd is on my bucket list and I wouldn't mind visiting Sugar Loaf Mountain and meeting Dan.
There's been recent talk of a meetup at Gainesville Raceway or Orlando Speed World. We've been drag racing at OSW since our track closed down.
