Code PO128 C6
Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 24
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From: Mt Top Pa
Code PO128 C6
Hi everyone, I just installed a 160 thermostat in my 2005 a few days ago, and I am getting a check engine light with code PO128, which is a "Coolant thermostat (coolant temp below thermostat regulating temperature) I talked with someone that has done lots of these and they said that it shouldn't be coming on, and the temp should still be around the 190 area. My wife came home from work with the car and I went out and checked, and the temp was 192. I started the car up a few hours later to put it in the garage and the light was back on with the same code. The car only has 10,200 miles on it. I think the only thing to do is take it back out and make sure it is not being pinched anywhere. Anybody else run into this problem, I sure would appreciate some advice. Thanks.................Phil
Safety Car
Joined: Feb 2008
Posts: 3,712
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From: TEXOMA
St. Jude Donor '08-'09
what Kind of 160 stat did you put in? and did you check it on the stove prior to installing?
some certain 160's have shown to open as low as 140 and be fully open by 160, while the 'oem' style ones open 160-165 and are fully open 175-180.
some certain 160's have shown to open as low as 140 and be fully open by 160, while the 'oem' style ones open 160-165 and are fully open 175-180.
Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 24
Likes: 0
From: Mt Top Pa
I placed a call to corvettes of westchester, and he said that to take it back out and reinstall it, that the gasket can get pinched,which results in bypassing the thermostat. I took it off and that 's what happened. You have to take off the hose and carefully put the thermostat in the housing, then tighten it up to 11Ft lbs.I did just that and problem solved. Thanks for all replys. I will be at Corvette Carlisle with my C6 and C2 My name is Phil, and i willbe in the 63-67 sting ray resgistery row with a 63 convertible.Stop by and say hi.
