1990 Base Timing/NO Start
Thread Starter
Instructor
Joined: Oct 2000
Posts: 130
Likes: 0
From: Clifton Park New York
1990 Base Timing/NO Start
Thanks to all that responded to my question last night. I decided that a little extra advance would be a good thing. Here's my problem now. When I unplug the ECM from the distributor (large multi pin connector behind distributor), the car will not start. It doesn't give any attempt. It just turns over. I put a timing light on a plug wire and did see that I am getting spark. It appears to me that when I unplug the distributor I disable the injectors. As soon as I connect the plug, it starts up instantly. I thought perhaps the base timing may be way out so I tried rotating the distributor off of the original mark while i cranked. I got nothing. It appears to me that I am getting no fuel. Okay I do have an Autoxray scanner. Is there some kind of criteria that would let me time it on the fly with the car running? If the injectors are disabled is there some means of jumpering them on? Thanks again
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
First thing to check is the injector fuses. On my 86 I can disconnect the EST and crank my car. You can also crank the car and then disconnect the EST. You are sure it was the EST right? Once the EST is disconnected the ECM can't control timing and then you can set base timing.
Pro
Joined: May 2005
Posts: 510
Likes: 0
From: crofton maryland
the EST wire is brown with a black stripe. you should see it from the drivers side of the engine bay. near the brake booster, not on the cap. get the car warm first, set up your timing light then do like the sticker on the rad says. my 1986 say 6 degrees in drive.
Thread Starter
Instructor
Joined: Oct 2000
Posts: 130
Likes: 0
From: Clifton Park New York
The plug I disconnected is on the back of the distributor. It is a large flat plug with 4 wires. The wires on the cap were left plugged in. I know it is not a fuse because when I reconnect the plug, all is well.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Originally Posted by 90Conv
The plug I disconnected is on the back of the distributor. It is a large flat plug with 4 wires.
Thread Starter
Instructor
Joined: Oct 2000
Posts: 130
Likes: 0
From: Clifton Park New York
I just ran out in the garage. I noticed a large bundle of wires behind the brake booster with a wire and plug coming out of it and tie wrapped along its side. The wire is a light brown almost beige with a black stripe. Could that be it or should I look some more?
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