Good day everyone, I’ve owned my c4 almost 4 years and the opportunity has come up for me to purchase a c6. The c4 has a backfire that I can’t find the cause. I’ve replaced everything and even removed the heads to find out the previous owner completely rebuilt the engine. So I’m looking to sell as is and let the next person figure it out. So I’m trying to figure out what I should sell it for. The odometer says 224k.  

The pricing would be dependent on the cause of the backfire.  What are the conditions that cause the backfire, and does it always backfire under those conditions, or is it intermittent?

Go to a site like CarGurus or one of the Blue Book types, fill in the info and get a price quote.  Don't be surprised at the dismally low price;  I have a nearly perfect '95 Z07 coupe in which everything works including all the functions of the Bose Sound system, has just over 40K miles, and a clear CarFax  and price is listed at less than $7,000, however, cars like mine listed for sale on the CarGuru site hover around $12,000 to $15,000.

It would be to your great advantage to know the cause of the backfire.

Good luck,        Dave

Thank you I will definitely do some homework