Cold Start Fuel Injector Problem
Thread Starter
Heel & Toe
Joined: Jul 2012
Posts: 19
Likes: 0
Cold Start Fuel Injector Problem
Have an 87 Coupe that is extremely difficult to start. Upon checking, I find that I have no power at the electrical connector for the cold start fuel injector. Does this signal come staight from the ECM or is there a relay involved?
Thanks for any suggestions you might have.
Thanks for any suggestions you might have.
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
cold start is controled by a temp sensor thur the ECM. Chances are if you are having dificulties durning the summer it is not Cold start related. In fact there are many who have deleted it completly and have not noticed a difference.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
The CSI is is a complete independent system controlled by a thermo switch / timer
The CSI switch at the front of intake that JackDidley mentions only has power to it when the starter is operational.
Switch is the brass hex head unit ( expensive ) next to the CTS circled
Cliff H will be along soon to repeat what I said
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Clarification is not the same as repetition...
The cold start thermo switch gets power from the starter solenoid, so it only has power on it while the engine is cranking. It has a thermal element inside that heats up and opens the circuit after 8 seconds. It also will not turn on if the coolant is above 95°F.
You can check the cold start injector switch with an ohmmeter. It should measure close to zero ohms when the engine is cold. It should be open (infinite resistance) when the engine is hot.
I paid $105 for one a few years ago, so yes they are expensive.
Your fuel pump relay could have a problem. Does it run for 2 seconds when you turn on the ignition? If not, the oil pressure backup switch might be coming on after the oil pressure gets up to 4 PSI.
The cold start thermo switch gets power from the starter solenoid, so it only has power on it while the engine is cranking. It has a thermal element inside that heats up and opens the circuit after 8 seconds. It also will not turn on if the coolant is above 95°F.
You can check the cold start injector switch with an ohmmeter. It should measure close to zero ohms when the engine is cold. It should be open (infinite resistance) when the engine is hot.
I paid $105 for one a few years ago, so yes they are expensive.
Your fuel pump relay could have a problem. Does it run for 2 seconds when you turn on the ignition? If not, the oil pressure backup switch might be coming on after the oil pressure gets up to 4 PSI.
