Fuel Composition Sensor (P0178) - SOLVED

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.

OR VietVet

Multnomah Falls
Supporting Member
Military
Joined
Oct 8, 2014
Posts
20,966
Reaction score
37,393
Location
Willamette Valley
Flex fuel engine fuel composition sensor, seen a few of these set that code here. Parts cannon dictates replacement because of it being inexpensive and easy to install.
 

OR VietVet

Multnomah Falls
Supporting Member
Military
Joined
Oct 8, 2014
Posts
20,966
Reaction score
37,393
Location
Willamette Valley
Inexpensive? On RA they are just under $400 each. OE.

I had seen threads about this before but my recollection was that it was not that expensive but $371 is not cheap for sure. Good thing he didn't just throw the part at it first and did the testing to be sure. Sorry @Fless

You also need to remember that I am a "thousandaire".
 
Last edited:
OP
OP
RAMurphy

RAMurphy

Bob
Supporting Member
Military
Joined
Oct 5, 2011
Posts
1,432
Reaction score
4,545
Location
S. Maryland
Yep, I laughed at the first post about "not expensive" but then again for some that may be cheap. That is why I checked out the wires first. The original has been on there for over 20 years and all those miles, so if you consider the cost per years or per mile - that damn thing is really cheap.
 

MassHoe04

Full Access Member
Joined
Nov 4, 2021
Posts
1,587
Reaction score
2,820
Location
Western MA
Yep, I laughed at the first post about "not expensive" but then again for some that may be cheap. That is why I checked out the wires first. The original has been on there for over 20 years and all those miles, so if you consider the cost per years or per mile - that damn thing is really cheap.
Yeah... Sorry about that comment about being relatively inexpensive!

I don't have FF. I was curious, so I took a quick peek on the interweb and the first things that popped up were like $100.

But for AC Delco... I guess one and done is not terrible for the $371.

NTK was $13 more. Not sure, but there is a very good chance they could have been the OE supplier to GM and making the AC Delco replacements.
If for some reason anyone is not able to get AC Delco, I would be able to put my trust in an NTK as an alternative replacement.

On the bright side, at least it will be an easy job to do!
 
OP
OP
RAMurphy

RAMurphy

Bob
Supporting Member
Military
Joined
Oct 5, 2011
Posts
1,432
Reaction score
4,545
Location
S. Maryland
Yeah... Sorry about that comment about being relatively inexpensive!

I don't have FF. I was curious, so I took a quick peek on the interweb and the first things that popped up were like $100.

But for AC Delco... I guess one and done is not terrible for the $371.

NTK was $13 more. Not sure, but there is a very good chance they could have been the OE supplier to GM and making the AC Delco replacements.
If for some reason anyone is not able to get AC Delco, I would be able to put my trust in an NTK as an alternative replacement.

On the bright side, at least it will be an easy job to do!
No issues or worries here.
 
OP
OP
RAMurphy

RAMurphy

Bob
Supporting Member
Military
Joined
Oct 5, 2011
Posts
1,432
Reaction score
4,545
Location
S. Maryland
Tahoe is up and ready for this change. I will do this tomorrow. While I'm under the vehicle and under basically the same location, I will also change out the evap canister.
 
OP
OP
RAMurphy

RAMurphy

Bob
Supporting Member
Military
Joined
Oct 5, 2011
Posts
1,432
Reaction score
4,545
Location
S. Maryland
Completed the part change. It took about 30 minutes or so - even after depressurizing the fuel lines I still took a bit of a fuel bath. Pretty easy job even in the confined space.

Old compensator:
20221202_110541_resized.jpg
20221202_111930_resized.jpg
New part installed:
20221202_113635_resized.jpg
 

Forum statistics

Threads
132,711
Posts
1,873,035
Members
97,532
Latest member
schimme
Top