View Full Version : Redtop Cold Start Issues and running poorly (Already replaced CTS)

05-09-2010, 02:46 PM

Ok, so I am an idiot so I am just making this a one post thread so hopefully in the future someone will maybe find it of value.(Read below to see why I say I am an idiot)

Symptoms: Car was extermely hard to start when cold. The first time I would start the car in the morning it would fire right up and stay at 1300rpm's for a couple of seconds then the rpm's would fall off and the car would die. After that first attempt the car was then extremely hard to get to fire up, after several attempts of pumping the gas and trying to start the car I would eventually get it running. Typically it would start up at some point and the idle would be 200-300rpm's and the car sounded horriable, after awhile it would slowing get ahold of itself and start to run normal. Once the car was warm it typically started fairly easily.

How I solved it: First checked my ecu for codes and thought I found the problem. Code 13 -coolant temperature sensor, this commonly will cause cold start issues and rough or hunting ilde. Replaced the CTS and it helped stable out my idle but did not fix my cold start issue. So then I starting thinking it was a vacuum leak because I had just installed the isis manifold (jumped to quicly on the bandwagon of thinking I had a nighmare because of a knockoff!). Chekced for boost and vacuum leaks only to find out that everything was great and could hold 30psi. So this whole time my brother suggested that I check the start signal to the ecu. Pin #34 on the ecu (#62 redtop ecu) is an orange wire with a silver stripe on the ecu section of harness and I believe just an orange wire on the chassis side (s13), it should get 12 volts when you try to start the car. This wire is in the same harness as your rpm and water temp signal that goes into your dash harness (white clip just above your ecu) I swore I checked it earlier before I started all this other trouble shooting. So yesterday I rechecked it after my brother kept hounding me, and low and behold the wire was not connected at all. Once I soldered the wire together the car starts up everytime.

As a side note, I mention in the title that my car ran poorly. My gut feel on that is the plugs where just getting messed up with all the trouble shooting ideas I was trying that where really doing nothing but messing more things up.

Lesson learned... don't be scared to check and recheck wiring!