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2002 gmc envoy_sle
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Discussion Starter #1 (Edited)
I replaced the valve cover gasket and intake gasket on my uncles 02' Envoy with an I6. Cleaned the throttle body and put in new spark plugs.

Now it won't start. It will kick over with starting fluid so I know I am getting spark.

I pulled the intake back off checking to see if I pinched a wire and found nothing.

Replaced the crank sensor. Didn't fix it.

Checked the fuel pressure and it showed zero but the pump was running. Replaced the pump today. Still no start. New pump shows zero pressure. I checked with two different gauges. I am going to pull the pintail out of the schrader valve and recheck the fuel pressure. At this point I am going to have to take it to a shop.

I am not going to throw anymore parts at this thing. I don't like that I put two parts on it that it didn't need. With no tech II or Modis it's tough to diagnose problems on the later model stuff.

I have double checked every connector I took off. The only thing I have not done is check to see if the injectors are firing. I pulled a spark plug out and it's bone dry.

I don't know what I could have done to induce this problem or if they are related. I think it might be because it ran before I worked on it. :duh:

Thanks for any help.

Jason
 

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Northwest Chapter
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11,824 Posts
PCM connectors seated fully?
Injector wiring reconnected securely?

Sounds like everything is good, except you're not getting any fuel. How's the fuel filter look? Check the rail pressure at the schrader valve (sounds like you're doing that now).

Know it sounds stupid, but is there fuel in the tank? No fuel = no fuel pressure.
 

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2002 gmc envoy_sle
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5 Posts
Discussion Starter #3 (Edited)
I have checked the PCM's connections several times and the injector harness plug on top of the valve cover.

The only test port I can find is the one next to the fuel filter. I replaced it when I replaced the pump.

There is fuel in the tank.

I don't understand how there is no pressure with the pump running. The odds of the fuel pump going out when I worked on it are high. Then the odds the replacement pump is bad too is crazy.

A friend of mine works at a dealership and went through the whole diagnostic tree and found nothing.

There are no DTC's and no security light on.
 

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2002 gmc envoy_sle
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Discussion Starter #4
The CPAS did have oil in the connector when I unhooked it. I cleaned it out when I put it back on.

I was reading the other thread about how to replace them. I wouldn't think it would keep it from starting.

That was my very first thought when it wouldn't start but I don't know enough about these engines to say that's it and I'll be damned if I will buy another part to put on it not knowing what the problem is.
 

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2002 gmc envoy_sle
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Discussion Starter #5
Well I fixed it. It was the power wire on the injector side of the harness.

I pulled the pintail out of the schrader valve and checked the fuel pressure. 60psi. Apparently the gauge wasn't pushing the pintail in.

I called my friend who is a GM mechanic and we started going through checking the injectors. I had power and the injectors were pulsing on the connector on the harness side. I decided to check the injector side of the plug in for power.

I was laying on top of the engine on my cell phone probing wires when the wire made contact inside the connector and the engine started. Scared the crap out of me.

The wire was broken off but still inside the weatherpack seal. I am going to the junk yard to get a new wire/wire end tomorrow.

:thumbsup:
 

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2002 chevy trailblazer_ltz
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30 Posts
Hi
Where is locate this wire harness?
Thanks
Adrian

Well I fixed it. It was the power wire on the injector side o the harness.

I pulled the pintail out of the schrader valve and checked the fuel pressure. 60psi. Apparently the gauge wasn't pushing the pintail in.

I called my friend who is a GM mechanic and we started going through checking the injectors. I had power and the injectors were pulsing on the connector on the harness side. I decided to check the injector side of the plug in for power.

I was laying on top of the engine on my cell phone probing wires when the wire made contact inside the connector and the engine started. Scared the crap out of me.

The wire was broken off but still inside the weatherpack seal. I am going to the junk yard to get a new wire/wire end tomorrow.

:thumbsup:
 

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2002 gmc envoy_sle
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5 Posts
Discussion Starter #7
You have to take the air box off the throttle body that sits on top of the valve cover. About 2/3's way back on the valve cover there is a wiring harness with a plug. One side is attached to the valve cover with a plastic push pin. That's the injector harness. The injector side goes behind the back of the intake and curves under going to the injectors. The engine harness side runs down the valve cover I believe.
 

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2002 chevy trailblazer_ltz
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Thank you very much LilJayV10:yes::tiphat



You have to take the air box off the throttle body that sits on top of the valve cover. About 2/3's way back on the valve cover there is a wiring harness with a plug. One side is attached to the valve cover with a plastic push pin. That's the injector harness. The injector side goes behind the back of the intake and curves under going to the injectors. The engine harness side runs down the valve cover I believe.
 
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