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Hello! I'm Rixster...
I'm going to help you out on this but I need some clarification on a couple of things...
You said you checked fuel pressure?
What was the reading in PSI? should be about 9-13 PSI.
Does this only happen when cold?
Okay so you have a CPFI engine and that reading is acceptable.
The Throttle Position Sensor Read is about right as well.
The Engine Coolant Temp. Sensor reading (14K ohms) tells me you are at about 0* F or lower.
Is this the case? If not it may be trying to overcompensate for a lower that true ambient temp. Are the plugs wet with fuel?
Is there good spark?
Can you get codes from the ECM?
Check these and get back to me and we'll see where we are going from there.
I don't recommend throwing an ECM at it just yet until we know for sure.
It's possible the injector is faulty.
The injector for this rig is located under the intake plenum. There is one injector and six little hoses with poppet valves on them that go to the individual ports.
If you replace this make sure you place the hoses the same way as they are placed on the original one.
You can check for proper pulse with a noid light attached to the injector harness.
This is a red and blue wire harness comes out at the front left side (right side as you look at it) of the ntake plenum. Disconnect this harness, plug the light into the vehicle side of the harness and crank it. Should see an intermittent flash to show injector is getting current. If you are getting good pulse then you know your injector is stuck open or malfunctioning.
No! Not that I know of.
You've basically done all the checking you really need to do. What it comes down to is
If the injector is faulty it's time to change it.
Pretty simple job. Don't forget to replace the plenum gasket too. You don't want to deal with vacuum leaks later!
Thank you so much. New injector seems to have cured starting problem. Having you confirm my husbands thoughts helped us to spend the $$$ on the part. Will be asking questions on our 1995 GMC Jimmy problems soon. How can I request you? Thanks again Rixster. Bill and Karen(the 93 is mine)
It's been fun helping. I'm glad to see all is well!
Thank you for your awesome comments. It really made my day.
You folks are awesome!
Sounds like you may have a bad connection there. If you are careful you can extract those wires out of the connector and inspect them for tension as well as the other side for staitness.
I would'nt rule out the possibility of a PCM Failure too.
Let Me Know!!!