I was trying to get the GTA started today and if it did fire up there was backfire noises from the engine and rear of the car..any idea what this could be from? 350 1989 large tube runners just installed

 

Check to see where the base timing is set and go over your spark plug wires and make sure there aren't any that have been crossed.

 

Tanks for the reply! I am checking that today then. Would either of those problems cause the engine to die out immediately after starting up. If I don't keep revving it up, it will shut off that second. Also, is there any cance I could have messed the timing up while installing the new runners?

 

It's highly unlikely you moved the car's timing by changing the runners, unless your distributor is loose and you bumped it during installation. If the car doesn't want to idle, take a look at your IAC, make sure it's functioning and the internals aren't gunked up. A search on here should show you the IAC adjustment procedure.

 

Today I checked the plug wires, everything ok. I checked the distributor, ok.I also did the papr clip light check. Flash,pause,flash,flash...I think that just means the SES light is working correctly. Checking the IAC today, anything else I should check. This is the last week I have to work on it myself. Thanks!!

 

Possibly fuel related? you said it will only stay running if you rev it. It could be leaning out due to the longer runners? i just got my camaro, so im just thinking about engines in a general sense, not the camaro specific engines.

 

When I put headers on my car we bumped teh CTS plug and basically broke it and we didnt even notice. Justo ne of those things that cropped up at the same time. if the CTS plug makes a bad connection the ecm gets the temperature WAY wrong and starts dumping tons of fuel in it and the onyl way to keep it running is... you guessed it, holding the throttle open.

 

Thanks for the replies...What is the CTS sensor, I did a search and didn't find a description of where it is or what it does exactly. Maybe this is my problem...

 

CTS = Coolant Temperature Sensor

The ECM uses this sensor to detect the temperature of the engine coolant. It also varies output based on the reading this sensor gives. If the sensor is broken, the ECM will get a constant read of being about -40°F, and it's going to cause problems.

 

Wow, I learn something new every day! Where is the CTS located? Is it replaceable? Thanks again... sorry to sound like an idiot. I am really frustrated with all the sensors in this car.

 

Should be located in the area underneath the throttle body, two prong plug. If the engine is warm or close to operating temperature, you can take a voltmeter and measure the resistance across the sensor. The ECM uses resistance from the sensor to measure the temperature.

So, if the car's at operating temperature, say around 195°F, the sensor should have about 240 Ohms resistance across its two prongs. The higher the resistance value, the colder the ECM thinks the car is.

If the car is at operating temperature, and for example you have ~9400 Ohms across the sensor, it's telling the ECM it's only 32°F, and it's a safe bet your sensor is shot.

If in the case it's bad, If memory serves a 7/8" wrench should fit it. You can replace it fairly easily.

 

OK, so checked everything. I am thinking maybe it is a fuel problem now, or timing. I have run out of time and took the car to my mechanic today. I will get back and let you all know what he says and what happens. Thanks for the help