rayres74
Member
I have had my 87 corvette for about 6 months now. I have noticed when on cold start up it races up around 9 to 1200 rpm until warms up then drops to about 600 rpm after approximately 30 seconds. Once warm and you start the engine again it races up again and will lower back down after about 10 seconds every time. Didn't think this was normal. Car drives fine when running down the road it just happens to buck when at idle every 10 to 20 seconds. Thought the engine would know that it was warm and would idle correctly. I have known that the idle should be at about 450 rpm in drive but mine it around 500 to 700 depending on it bucking when at a stop. I am not a mechanic but am definitely mechanically and electronically inclined. Could anyone lead me in a good direction? My engine is totally stock. I am getting a check code of 32 by jumping A B pins. First I get "12" 3 times then it goes to "32" 3 times and back again. I was hoping 12 is just saying that it is in diagnostic mode since that was a general code for GM. Then it showing 32 was the real issue. I also have a 91 gta and it also reads 12 first so I thought this was normal. I hope I am right on the 32 could be 23. Damn I will have to do it again in the morning. Any ideas from anyone? Should it be idling this high or should it really be at 450 in drive? What is the easiest way to set the tps and details on how to do it? My head gaskets were just replaced from an over heat because of a fan relay. He said the check engine had to do with 02 reading but it could be showing that cause of all the coolant blowing out through the exhaust when it happened. He said if it didn't stop coming on he would replace the o2 sensor. Well it hasn't stopped but I believe if you want something done right do it yourself. Just not sure my mechanic is all there with this engine and would like to make sure myself.