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I have a 1998 4.3 chevy wwith the spider type injection. I am getting 61 lbs of fuel and good spark. When testing the injector wiring with a test light , I get a completed curcuit without the engine even cranking. Is this normal? I thought one wire was


fuel pressure is good - spark

fuel pressure is good - spark is good - are the injectors failing? have you checked fuses and power at the injectors? is there a check engine lite?

I am getting voltage to the

I am getting voltage to the injectors. I am not getting fuel. Aren't the injector wires hot when the switch is on and the pcm sends a ground signal when engine is cranked to open the injector? I am getting one wire hot and one wire ground at all times. Thanks

The pink wires going to each

The pink wires going to each injector is the "power" wire. It should have power when the ign switch is on. the other wire a the injector is the ground wire (goes to the PCM). You can rent a "Noid-light" from autozone and use it to check the injector circuit.
If the injector circuit is good, check injector operation by spraying carb cleaner into the intake manifold (at the throttle body). Put the air cleaner system back in place and then try to start the engine. If it starts now then you know that the injectors are not opening (shorted or grounded). It's not likely that they will all short out at the same time.

The pink wires are hot when

The pink wires are hot when ign. is on. All the other injector wires (from PCM ) show ground at all times. Should'nt they not show grounded until engine is cranked? And then just one at a time. Engine runs great on starting fluid until you stop spraying. Could this be crank sensor? Bad ground? Thanks

The PCM measures the amount

The PCM measures the amount of airflow through the TPS and MAP sensor. Right now the PCM thinks the engine has no airflow, so it won’t spray any fuel into the intake. By spraying starter fluid or carburetor cleaner into the intake you are basically replacing the PCM. The truck will start and continue to run for as long as you continue to spray starter fluid or carburetor cleaner into the intake. “Spider” and “Poppet” failure is very common on these vehicles. However, before ruling in a spider or poppet issue you have to rule out a TPS or MAP sensor issue. BTW, are there any codes?

No codes. It also sometimes

No codes. It also sometimes backfires as you turn off the ign. switch. New TPS. The injector wires pulse as engine cranks. Cleaned ground wires to body and frame. This one has me confussed. I guess I forgot one small detail. I bought this van from a dealer. It would not start by the key switch but it would run by the remote. His mechanic then removed all the remote wiring thinking this would fix the problem. What was he thinking? I thought, heck I can fix this. I was WRONG!

(Quote) It would not start by

(Quote) It would not start by the key switch but it would run by the remote. His mechanic then removed all the remote wiring.

Ok, believe it or not that makes sense. It simply means that there’s an electrical connection issue present. It’s not just a matter of removing the remote wiring. In the process of removing the remote wiring you also have to restore the original “OE” wiring. It’s more than likely that the mechanic who removed the remote wiring didn’t connect back one or more of the original “OE” wires correctly. Another possibility is that the mechanic removed the remote wires and just twisted together the “OE” wires and then just wrapped some black electrical tape around them. This procedure is completely wrong, and opens the door for bad connections. When making electrical connections in any vehicle, all connections must be soldered and terminated in “Shrink Tubing”. Black electrical tape must never be used. Confirm all the electrical connections made by the previous mechanic. If necessary use solder and shrink tubing. Jiggle around the harness connections that the previous mechanic made. If the truck starts you know you a connection (or connections) issue.

Thanks for everyones help.

Thanks for everyones help. I'll try again tomorrow.


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