After the shop's owner decided to take matters into his own hands, police let one of the suspects go once he was caught.
Sal Wazni who owns Grand River Auto in Detroit has had enough. Over the last year he claims the same two crooks with the same black Ford Fusion have been stealing from customer cars parked in his lot at least six times.
"Stealing rims, batteries catalytic converters," Wazni said. "It's costing us every time they steal, $700, $800. We just have to pay it all the time, and take care of the customers and buy them new stuff."
So Wazni set up his own security sting and caught them in the act.
Wazni purposely parked his newer car in the lot as bait while security cameras were rolling.
On tape you can watch the man walk up to his white Envoy, but what the thief didn't know was that Wazni was waiting in the back seat.
Wazni popped up, the guy ran away and took off in the Fusion but he left his lookout guy behind him.
"He left his buddy out here," Wazni said. "I had his buddy, I told him not to leave and called 911 immediately. The cops came, interviewed him and let him go."
Ryan Ladach, who works at the shop, says he tried to help the cops and he's the one who earned a seat in the back of the cruiser.
"They twisted my arm back, handcuffed me, put me in the back of the cop car," Ladach said. "Because I was bothering their investigation."
FOX 2: "What were you trying to do?"
"Help them," Ladach said. "Show them the cameras. We got them on camera and they didn't want to look at it."
Still waiting hear from police why they let the suspect go and why according to Wazni, they're not investigating the numerous car part thefts.
"I caught the guy, waited for police and they let him go," Wazni said.
Wazni said he wanted to offer $1,000 to anyone who can identify the suspects and give information to get them prosecuted.
Call the Grand River Auto Service at 313-414-1220.