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I just got done putting my 87 back together from doing valve seals and replacing the distributor, plugs and wires. It starts up and dies immediately. I can’t give any throttle. I’ve looked over it for a plug or something I missed putting it back together but I can’t find anything. Checked for codes and there are none.
I’m looking for ideas on what to check. Sometimes after looking at it for so long I can’t see what might be right in front of my face.
What would cause this? Im sure it’s something simple. Feels like the ignition cuts off or the fuel pump cuts off right after it starts. Only runs for a second or two.
Does it run well for a second or just sputter / hit a miss a few times barely spinning over ? The FSM states the tach wire should never be grounded. If the tach wire is grounded it will start and stall and this occurs sometimes when people install tachometers that are not compatible with the HEI system.
I think we are all hitting around the distributor as the problem. I was trying to see what excites the ICM with the key on and what has to take over when the key is released but what I have to search for IHBD has in his head.
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Maybe, though I had that problem on my 89 and it turned out to be the O2 sensor. I would also double-check your TPS AND IAC to make sure they are plugged and mounted correctly. After all, the IAC (and throttle body should provide enough air to command fueling -- to keep it running. (That's why sensing air on the back end is also necessary).
At the top of the diagram, there is an orange line to an oil pressure switch that takes over from the computer to run the fuel pump. It sounds like this is where your problem is. Maybe you haven't hooked that back up again. It's separate from the oil pressure sensor for your gauges. If you short out the relay contacts E to A, to get the pump running continuously, your engine should run, and this is how you can check it. Good luck!
Thank you all for the great tips.
I think the o2 sensor isn’t used until the engine warms up. I had that problem a few months ago and found the o2 sensor to be the problem so it’s only a couple months old. As is the fuel pump and filter.
Today I checked the fuel pressure. It comes up to 38ish psi when primed and stays up when the engine starts and dies. So the pump and relay seem to be functioning.
I also put a timing light on it to make sure it was firing. The light seemed to keep flashing even as the engine died. So it doesn’t seem like the distributor (maybe).
I looked over it again with a flash light to try to find something disconnected. Unplugged and re connected the distributor, idle, throttle body plugs to make sure they are seated correctly. I like the idea of spraying starting fluid to try to keep it running. I’ll try that.
still searching. Thanks for helping me brainstorm. We’ll get it figured out and I’ll be sure to report back when I find it.
I tried the starting fluid and it will run as long as I’m spraying it. Does this mean the injectors are shutting down after it starts?
Is there a way to check power to the injectors while/after cranking?
Does the oil pressure sender control this as mentioned above?
Where it’s the sender? Is it the one under the distributor? That one is still plugged in.
I think I’ll pull the distributor this weekend and make sure I didn’t disconnect or break anything.
The oil pressure sensor (gauge) and oil pressure switch (fuel pump) should both be located at the rear of the engine, beside the distributor, on a T fitting that uses the same source of oil pressure out of the block. The connector should have an orange wire and a tan/white wire. Remove this connector and jumper the wires to connect them together. This should turn on the pump and allow the engine to run continuously.
The oil pressure sensor (gauge) and oil pressure switch (fuel pump) should both be located at the rear of the engine, beside the distributor, on a T fitting that uses the same source of oil pressure out of the block. The connector should have an orange wire and a tan/white wire. Remove this connector and jumper the wires to connect them together. This should turn on the pump and allow the engine to run continuously.
I tried the starting fluid and it will run as long as I’m spraying it. Does this mean the injectors are shutting down after it starts?
Is there a way to check power to the injectors while/after cranking?
Does the oil pressure sender control this as mentioned above?
Where it’s the sender? Is it the one under the distributor? That one is still plugged in.
I think I’ll pull the distributor this weekend and make sure I didn’t disconnect or break anything.
Success!
we figured it out.
I humbly submit for your forgiveness.
it was the distributor oil drive. I thought I had it all the way in. It felt like us slipped back into place. It’s hard to see under there. That’s why the engine would shut down on the oil pressure sender. Good engineering by GM if you ask me. I’m lucky it didn’t start.
When I removed the distributor to check the plugs underneath it a lightbulb went off that this could be the problem. I went through the whole retiming process. Set it to tdc, installed the distributor, turned the engine by hand until it dropped into the oil pump. It started and kept running. I set the timing at 6btdc. It runs great now.
I wanted to be sure to post my solution incase anyone does the same bonehead move that I did.
Thanks for all the suggestions. It really helped me think through it.
Starts and dies immediately
