96 Tahoe dies while driving and won't start

[Nightflyer]

Hey Guys,

I'm back from Greece (Crete) and i hace the new spider-injector... I'll hope the weather is on sunday okay so i can fix my chevy (no garage).

Best regards

 

[Nightflyer]

Okay,

New injectors don't fix the problem....no fuel in the engine. All spark plugs are dry....

Fuel pressure is okay, good spark, etc...but no fuel at the injectors

What can i do...???

Best regards

Matthias

 

[east302]

Any trouble codes? P1336 for CKP variation? Did they do the relearn procedure when that sensor was replaced? I think the engine has to be running to do it, but it should throw a code if the VCM isn't seeing the right value from the sensor.

What are your scanner readings for the throttle position sensor (should be below 2.5V with throttle closed) and your engine coolant temperature sensor (should be close to ambient temperature at first).

Did you check to see if the VCM is providing a ground for each injector when cranking? You'd use a noid light normally, but a test light may work as well.

 

[Nightflyer]

Hi east302,

There are no trouble codes stored.

The relearn procedure is done since I've changed the ckp and the chevy runs well.

TPS sensor voltage is not able to read with my scan program. The ECT display the correct temperature.

I've tested the blk wires with a test light and the positive port off the battery. It's not flashing while cranking....

Does it mean that there is no signal from the ecm to the injectors?

What about the cam sensor? Could it be?

Or something else......?

Aaaargh......

Matthias

 

[Nightflyer]

Or how do I test the signal to the injectors?

Maybe I did it not the right way?

Best regards

 

[Nightflyer]

Okay,

I noticed a few strange things: i tried to generate some trouble codes.

Unplug CKP: trouble code
Unplug MAF-Sensor: trouble code
Unplug CAM-Sensor: no trouble code
Unplug TPS: no trouble code
Unplug ECT: trouble code

When i took a look at the "live data" from my chevy, my diagnosis-software show me some strange values:




I don't believe, that this is normal when the car is not running.

Best regards with cold beer in my hands..

Matthias

 

[Nightflyer]

By the way:

I'm using scanXL pro (Palmer)

 

[east302]

Or how do I test the signal to the injectors?

Maybe I did it not the right way?

Best regards

See posts 11 and 16. The ideal way would be to jumper the voltage and VCM feeds with a noid light to see if it grounds during cranking. A test lamp may work, but I'm not sure if it could respond fast enough.

 

[Nightflyer]

Does your scanner have history data for cylinder misfires?

Well, you've got fuel (or too much, which cylinders were flooded?), spark and air.

The next step, since you have power to the injector harness, would be to see if the computer is grounding each injector during cranking. A noid light would normally be used to see if it flashes during cranking, but you may have to rig something up to fit the spacing between the voltage supply and VCM circuit terminals in the main harness.

Or, you could put a test light to battery positive and probe the ground (or test light across the two terminals) to each injector during cranking and see if the light flashes.


Sent from my iPhone using Tapatalk

Okay,

I'll hope i understand you:

Testing voltage at the injectors: Pink wire connected to ground: there are 12 volts.

Testlight while cranking: Testlight between pink wire and the "black-lined-wires" or between the black wires and the battery positve connector? I've found this discrpition: https://www.2carpros.com/articles/how-to-test-a-fuel-injector

 

[Nightflyer]

I've done it like discribed in the link: my Testlight didn't flash....(I've used an LED)