Engine starts but won't stay running- Help!

[DonziDan16]

Here's the story- I replaced the stock manifolds on the 4.3 with aluminum IMCOs. I tried to start it up but was having trouble starting and when it did fire, it would shut off immediately. I replaced the ignition switch and it fired right up. But it was idling really rough and would sometimes die because of it. It was fine if I idled it up a bit. After dying and restarting a couple times it became worse and now it only runs for a second or two before the engine dies. It ran fine before I switched to the new manifolds but I don't know why that would cause this sort of problem. Any ideas? Someone suggested it might be a fuel filter problem.

I really want to get in the water before the 4th! :shocking:

[Pismo]

Fuel, you have spark so..

[Pismo]

Standpipe plugged, filter plugged, pump bad, carb plugged, etc.

[Trueser]

Did you pull the plug wires when you installed the Manifolds? check to make sure they are on the correct cyl. Or you my have cracked a plug or two.

It has to be some kind of wire issue. Is the ECM mounted on the manifolds and grounded properly?

[mrfixxall]

Here's the story- I replaced the stock manifolds on the 4.3 with aluminum IMCOs. I tried to start it up but was having trouble starting and when it did fire, it would shut off immediately. I replaced the ignition switch and it fired right up. But it was idling really rough and would sometimes die because of it. It was fine if I idled it up a bit. After dying and restarting a couple times it became worse and now it only runs for a second or two before the engine dies. It ran fine before I switched to the new manifolds but I don't know why that would cause this sort of problem. Any ideas? Someone suggested it might be a fuel filter problem.

I really want to get in the water before the 4th! :shocking:

Your ignition coil may have took a crap!

[ITTLFLI]

Your ignition coil may have took a crap!

:wink:


Check to make sure the coil is "hot" with a test light. Do this with the key in the "run" position.

[justleft]

Pinched fuel line ?

Check everything around the new exhaust. I cracked 2 spark plugs
changing to headers.