2003 Chevy Trailblazer- Will Not Start

[Truck]

2003 Chevrolet Trailblazer cranks but will not turnover and the service brake system msg comes up on the dash

 

[Mooseman]

So you're saying it cranks but will not start? Step inside...

Cranks but won't start

The service brake system message is unrelated. You would need to pull the brake/ABS codes for that.

 

[Truck]

Yes, cranks but will not start.

 

[flyboy2610]

Does the security light on the dashboard flash?

 

[Mooseman]

Try looking at this thread?

D

Thread 'Cranks but won't start'

Feb 18, 2014

When I turn the key on my 2004 trailblazer it will not start.Just keeps cranking.I have replaced the ignition switch and it still won't start.Could anyone please direct me on common issues that may be causing my trailblazer to not start?

• Dave347
• Replies: 265
• Forum: Vortec 4.2L I-6

 

[Truck]

Changed The Cam Shaft Position Sensor and still not starting

 

[Mooseman]

Moved your post to this existing thread to keep things together.

What led you to think that the camshaft sensor needed to be replaced? Normally, the cam sensor would not prevent the engine from starting.

Did you read through the thread I posted? It has lots of info regarding where to check. We need more information about what's going on.

 

[budwich]

2003 Chevrolet Trailblazer cranks but will not turnover and the service brake system msg comes up on the dash

Is your check engine light ON?

 

[Truck]

Moved your post to this existing thread to keep things together.

What led you to think that the camshaft sensor needed to be replaced? Normally, the cam sensor would not prevent the engine from starting.

Did you read through the thread I posted? It has lots of info regarding where to check. We need more information about what's going on.

I pulled the P)340 Code with my code reader

 

[movietvet]

So, are you saying the engine would turn over/crank/spin and would not start. Then you pulled a code P340 and replaced the cam sensor. Then the engine still turns over/cranks/spins and no start? Correct.
What brand cam sensor did you install?

 

[Truck]

I pulled the P)340 Code with my code reader

OEM #12584079

 

[Truck]

OEM #12584079

Yes Pulled the code and replaced the Cam Sensor.

 

[Truck]

Yes Pulled the code and replaced the Cam Sensor.

And it still cranks and will not start.

 

[movietvet]

You didn't answer all my questions. Initially, was the problem a "crank over and no start condition"? Before you pulled the code.

If so, did it run and sit overnight and then the crank and no start problem?

Answers to ALL questions, let us be there instead of doing guesswork.

Was the "service brake system" message there before or did it show when this problem occurred? Doubt it. The message should not show for this problem or have anything to do with a no start condition, like @Mooseman said.

If was not there and is new, maybe-just maybe a shared ground problem??????

 

[budwich]

is the p0340 code still present?

 

[Truck]

is the p0340 code still present?

My Son drove the car 16 miles away to work. When he tried to return the car stalled out and had to be pushed out of the traffic. I had the car towed home that night. The next morning I tried to start it up and it only cranked. No starting and the service brake system msg came up on the dash. I tried to jump it and then the same thing. Pulled the code P0340 after that and then I replaced the cam shaft sensor because the code was Cam shaft sensor. It still did not start after that. The never did run again after I had it towed home.

 

[mrrsm]

If your son observed that the Engine Stall happened when making a Left Turn... There is a unique problem with the Trallblazer LL8 4.2L Engine dying due to the fact that THREE DIFFERENT MODULES share a Common Ground and all three can conspire to cause the Engine to DIE if THESE Engine Block Grounds are either Broken, Loose or suffer from Galvanic Corrosion. Be advised that The Left Head Lamp, The Left Turn Signal ...AND... The Fuel Pump Relay located in the Fuse Box under the hood ALL Share the G-107 Engine Block Ground as shown below:



IF the Grounds on the Left (Driver's) Side of the Engine Block are compromised... whenever making a Left Turn with the Left Turn Signal engaged...the Left Headlamp will begin to flutter and the Fuel Pump Relay will DROP OUT due to an excessive amperage draw by all three modules occurring simultaneously and the FUEL PUMP WILL DIE AND CAUSE AN IMMEDIATE ENGINE STALL.

As per a prior suggestion made by @movietvet ...If this becomes proven by a physical inspection... the Solution is to Remove These Grounds from the Engine Block, . Clean all surfaces down to Bare Metal..., then Apply a Dollop of Dielectric Grease in between all the contact surfaces and Snug the Grounds back up against the Engine Block as shown in the encircled highlights in the photo just above.

Also... Recently... Thanks to the suggestions made by @TJBaker57 to another Member on a different Truck Platform that the problem might be evolving with Open Circuit Copper Wire Traces hidden and sandwiched in between the design of the Fuse Box...



...That Member investigated and found BROKEN COPPER WIRE TRACES in dwelling and was able to *Re-Wire* those in place with 20 GA Solid Copper Wire and this fixed his issue. These Videos show precisely how this action is performed:

 

[Mooseman]

The P0340 is probably just coincidental as I have run mine with the cam sensor disconnected.

You have to determine what is missing. To quote @The_Roadie in this old thread:

Classic flowcharting of this has three initial categories. Fuel, air spark. Fuel: check fuel pressure, listen for fuel pump, spray starting fluid into the intake. Air: observe throttle body butterfly plate with the resonator removed. Spark: check coil-related fuses, Wiring harness after the ignition switch, pull coil and plug to observe spark.

Once determined what's missing, we can go from there.