Green Lantern Vol 2 #52 - CGC 5.0

After reading a letter from Hal Jordan, Pieface pulls out his Green Lantern case book and recounts a previously untold story:

Sometime before Hal left Coast City, he was visited by Alan Scott from Earth-Two, who has come for Doiby Dickles's car Goitrude to bring to Doiby to commemorate the first year anniversary of his marriage with Princess Peril. Going to Hal's garage to retrieve the car, the two men are shocked to find that Goitrude has been stolen.

Changing into their Green Lantern guises the two heroes contact Doiby who travels to Earth-One to help them find Goitrude. The trio find the car, which apparently has a mind of its own and is helping crooks commit robberies. However, when the Green Lanterns try to attack Goitrude, it immobilizes them with a yellow energy beam. Goitrude then wills their power rings to charge her with energy which causes her to explode, revealing the sentient lifeform inside's true identity: Sinestro.

Taking Doiby's power ring, Sinestro and the crooks head towards Oa to attack the Guardians. When the two Green Lanterns and Doiby are freed, the three travel to Oa themselves where Hal and Alan manage to defeat Sinestro's army of "Sinestro's" and defeat Sinestro himself knocking him out with a combination of their power rings and hand to hand fighting. After the battle is over, the two heroes present Doiby with a miniaturized version of Goitrude to take home with him, before the two part company for their respective Earth's once more.