Have a few issues with my 96 Camaro z28 that I"ve owned for 4 years.

First off after about 20 mins of driving the car will get up to 250 degrees(right at red) then the fan will kick on and drop it to 230 degress then repeat the process. I know these motors run warm but thats a little too high for me. Just bought a new transmission so I dont want to be running it too hot. Any suggestions on whats going on? Over the past 2 years I have replaced the following with no change...Radiator, hoses(minus anything heater related), water pump, coolant temp sensor, 180 thermostat and switched to green coolant. Would love to get this problem fixed.

Second ever since ive had the car its always had loud popping/crackling and even sometimes a really loud backfire bang coming from the exhaust on deceleration. It has stock manifolds with cats into 2.5 inch full exhaust with no muffler, and pipes out the back. I'm sure the exhaust has something to do with most of the crackling but not so sure about the occasional loud backfire..

Third I have replaced the Opti five times over the past three years. The most recent one was four months ago maybe. Well at about two months after the install i decide to check my SES codes(its always on because my AIR is gone). The codes come back and I have a Crankshaft Postion Sensor failure code. So I go replace it and delete the code. Start the car and let it idle, code comes back within 30 seconds. I read that sometimes this means the Opti is on its way out the door. I sure hope not, please tell me different.

Last but not least I have a problem with the ABS INOP, ASR, and BRAKE light come on occasionally. Mainly after the car sat for a night, they will come on and stay on unless I turn the car off and restart it, then they wont come back for a day or so. I have 17x9.5 275/40 in the front and 18x10.5 315/30 in the rears.

 

What are your mods, ALL of them?

How are you bleeding the cooling system? Sounds like you may have some air in the system. If you're completely sure it's being bled properly I'd do a coolant pressure test. Also verify that your air dam is still in place.

A slight pop/misfire could be a ton of different things, but the exhaust isn't helping much. When I was bolt-on only my car ran strong but always had a slight pop on deceleration (unburned fuel being ignited in the exhaust).

Five optis over 3 years is pretty ridiculous. What brand are you installing? Parts store optis are incredibly unreliable. Personally I would delete/unplug the CPS. All it's there for is to detect misfires. OBDI cars have no such sensor so it isn't pertinent especially on a performance-oriented vehicle.

For the brake codes you can have them scanned at the dealer (EBCM) to tell you what's going on. I'd assume the two different OD tires (front to rear) may have something to do with it.

 

The motor is completely stock internally, just an aftermarket intake and the exhaust I stated. I bleed the system by running the motor with cap off until no bubbles are coming up. The opti failures are sorta my fault because two of the ones I replaced where new while the others were used off motors I bought. The times I bought brand new was the first time(shop did everything so idk if it was a Delphi unit), and this last time(bought it from a trusted source and I confirmed it was a gm unit. So far no symptoms of failure yet. Brake lights I'll scan with the Genesis when I get to class later.

Big cruise and racing in town on Saturday just want to make sure the car is in tip top shape. Also swapping trans today so I want to car to be healthly.

 

The temp has done that for a long time. I installed a switch to keep the fans on all the time(ran constant 180-200 degrees). Eventually got sick of the switch so I took it out. Ran at 230-250 before the switch and after the switch. Coolant gets low over time but not that bad. No leaks under the car whatsoever.

 

steam pipe over time gets clogged and can do what you describe.
maybe the heater lines or core as well.

 

Gotcha, thanks I'll check into that today.

 

Theres your overheating problem, LT1's are reverse flow you have to add coolant with the engine off and crack open the bleeder on the heater line until coolant comes out with no air. They close it and run the car with the heat on full blast with the radiator cap off, run long enough for the thernostat to open and hot heat then shut it off and let it sit with the cap off till it cools. then top it off and cap it off and your done.