cold start injector question
Thread Starter
Melting Slicks
Joined: Jan 2001
Posts: 2,996
Likes: 304
From: MOORESVILLE NC
cold start injector question
I own a 88 that has the so called 9th injector, Cold Start Injector, that I think was discontinued on the 89. I understand it is used only during initial cranking at a certain temperature. There are no rebuild suggestions on this injector. Change "o-rings" I guess. Is this injector necessary any more? I can find no information where it will set a Code. Did the change to different injectors in 89 cause the 9th to be dropped? Can the 9th be treminated at the electrical connection? I am upgrading to Bosch III injectors during this rebuild. Just curious. Does anyone have a digital pic of the injector mounted?
Race Director
Joined: Sep 2003
Posts: 16,836
Likes: 337
From: Database Error Indiana
9th injector is no big deal. As long as its not leaking it can be there and not work or you can remove it and plug the hole. I ran my 87, a couple years with it not working. Started in 10* F weather. Took a little more cranking to start cold but not enough to be a problem. You can have a chip burned with a newer bin that compensates and you will never know its not working. Not required but it s no big problem to do.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The 9th injector is controlled by the cold start switch, which is mounted on the front of the intake manifold under the throttle body. It has a connector that looks like the fuel injector connectors. This switch only operates while cranking. It has a thermal element inside that heats up and opens the switch after 8 seconds or if the coolant temperature is above 95 degrees.
The cold start injector is on the driver's side under the PCV valve tube. In this picture it's the round gray thing. The tube coming out of it goes to the back of the driver's side fuel rail. The connector that goes to the cold start switch is on the rear side.
It has no connection to the ECM so it will not set any codes.
The '89 and later compensated for the lack of the cold start injector by richening the mixture during cranking. It was done by changing the firmware.
The cold start injector is on the driver's side under the PCV valve tube. In this picture it's the round gray thing. The tube coming out of it goes to the back of the driver's side fuel rail. The connector that goes to the cold start switch is on the rear side.
It has no connection to the ECM so it will not set any codes.
The '89 and later compensated for the lack of the cold start injector by richening the mixture during cranking. It was done by changing the firmware.
Pro
Joined: Jun 2007
Posts: 626
Likes: 2
From: Coquitlam British Columbia
When I had my Formula 350 (L98) Firebird; I took the 9th injector off. Accel had a kit that plugged the spot where the injector was in the intake and a plug at the back of the fuel rail. Took the whole unit off and cleaned up the looks. Did it about 18-20 years ago, Bought the Accel kit from Summit.
Bill
Bill
Thread Starter
Melting Slicks
Joined: Jan 2001
Posts: 2,996
Likes: 304
From: MOORESVILLE NC
Called Jon at FIC and was told that a O-ring rebuild kit is included for thr 9th injector along with gaskets and O-rings for the fuel rails so I guess I'll put it back on. Thanks for the pic Cliff.
