• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

'05 Z71 Will Not Start After Maintenance

TFjed

Full Member
Joined
Sep 11, 2021
Messages
64
Location
Fairmont, MN
Got my engine all buttoned up after the oil pump, timing chain etc. and now it won't start. Turns over and over then stops after awhile. There are messages about servicing the brake system as well as stability, and the TC light and ABS lights are on. I'm waiting for new lower control arms because the ones I ordered got damaged in shipping, so there is literally nothing beyond the front differential down there. Is it just because the sensors aren't hooked up that it simply won't start?

Hooked up my BlueDriver and got the following codes:

C0035, C0040: Both for Wheel Speed Sensors

Also 2 codes related to HVAC, which I'm guessing have nothing to do with it.

Battery was at 12.27 when I tested it.

It's been sitting on jacks for a few weeks now because of unforseen issues, so was i initially thinking the gas just drained away from the engine. Not much of a theory but..

If anyone has any ideas I'd really appreciate it! Really want to get this done and start a thread all about this project.

And yes, the timing marks are lined up (in case that comes up)
 
Last edited:
Just some ponderings:

Timing would be suspect. Did you do any distributor work, sometimes that is not installed properly with the timing.

Do you have spark?
Have you tested the fuel injection at the intake to be sure you have fuel?
 
Distributor?

I'd have to look up to see how to test the fuel injection system, but I am getting fuel from what I can tell. I can smell it at the throttle body. I thought of checking spark, but all was good when parked so not sure why that would suddenly be an issue.
 
Here's pressure test procedure, I just posted a bunch of stuff you may or may not need. Anyhow, hopefully it will help someone, somewhere, sometime...

The pressure should be:

385-425 kPa (55-62 psi)

VIN Z : 335-375 kPa (48-54 psi)


Fuel Pressure Gage Installation and Removal​

Installation Procedure

Tools Required
J 34730-1A Fuel Pressure Gage



Caution

Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.






Caution

Wrap a shop towel around the fuel pressure connection in order to reduce the risk of fire and personal injury. The towel will absorb any fuel leakage that occurs during the connection of the fuel pressure gage. Place the towel in an approved container when the connection of the fuel pressure gage is complete.


1657675694221.png

  1. Remove the engine sight shield. Refer to Engine Sight Shield Replacement in Engine Mechanical-4.8L, 5.3L, and 6.0L.
  2. Remove the fuel rail pressure fitting cap.
  3. Connect the J 34730-1A to the fuel pressure valve. Wrap a shop towel around the fitting while connecting the gage in order to avoid spillage.
  4. Install the bleed hose on J 34730-1A into an approved container.

Removal Procedure


1657675713228.png
  1. Remove the bleed hose on the J 34730-1A from the approved container.
  2. Remove the shop towel from around the fitting and discard into an approved container.
  3. Disconnect the J 34730-1A from the fuel pressure valve.
  4. Install the fuel rail pressure fitting cap.
  5. Install the engine sight shield. Refer to Engine Sight Shield Replacement in Engine Mechanical-4.8L, 5.3L, and 6.0L.

Document ID# 803489
2005 Chevrolet Avalanche - 4WD
 
Last edited:

Fuel Injector Coil Test​

Circuit Description

The control module enables the appropriate fuel injector pulse for each cylinder. Ignition voltage is supplied directly to the fuel injectors. The control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance that is too high or too low will affect engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel injector coil windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector increases.

Diagnostic Aids

The use of Dielectric compound GM P/N 12377900 (Canadian P/N 10953529) in the fuel injector electrical connector may eliminate a corrosion condition.
Monitoring the misfire current counters, or misfire graph, may help isolate the fuel injector that is causing the condition.
Operating the vehicle over a wide temperature range may help isolate the fuel injector that is causing the condition.
Perform the fuel injector coil test within the conditions of the customers concern. A fuel injector condition may only be apparent at a certain temperature, or under certain conditions.
If the fuel injector coil test does not isolate the condition perform the fuel injector balance test. Refer to Fuel Injector Balance Test with Special Tool or Fuel Injector Balance Test with Tech 2 .
Step​
Action​
Values​
Yes​
No​
1​
Did you perform the Diagnostic System Check - Vehicle?​
--​
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information​
2​
Observe the ECT sensor parameter with a scan tool.
Is the ECT sensor parameter within the specified range?​
10-32°C (50-90°F)​
Go to Step 3
Go to Step 4
3​
Measure the resistance of each fuel injector with a DMM. Refer to Testing for Continuity in Wiring Systems.
Do any of the fuel injectors display a resistance outside the specified range?​
11-14 ohms​
Go to Step 6
Go to Diagnostic Aids​
4​
  1. Measure the resistance of each fuel injector with a DMM. Refer to Testing for Continuity in Wiring Systems.
  2. Record each fuel injector value.
  3. Subtract the lowest resistance value from the highest resistance value.
Is the difference equal to, or less than, the specified value?​
3 ohms​
Go to Step 5
5​
  1. Add all of the fuel injector resistance values, to obtain a total resistance value.
  2. Divide the total resistance value by the number of fuel injectors, to obtain an average resistance value.
  3. Subtract the lowest individual fuel injector resistance value from the average resistance value.
  4. Compute the difference between the highest individual fuel injector resistance value and the average resistance value.
  5. Replace the fuel injector that displays the greatest resistance difference, above or below the average. Refer to Fuel Injector Replacement .
Did you complete the replacement?​
--​
Go to Step 7
--​
6​
Replace the fuel injector or fuel injectors that are out of the specified range. Refer to Fuel Injector Replacement .
Did you complete the replacement?​
11-14 ohms​
Go to Step 7
--​
7​
Operate the system in order to verify the repair.
Did you correct the condition?​
--​
System OK​
Go to Step 2

Document ID# 1400187
2005 Chevrolet Avalanche - 4WD
 

Fuel System Diagnosis​

System Description

The control module enables the fuel pump relay when the ignition switch is turned ON. The control module will disable the fuel pump relay within two seconds unless the control module detects ignition reference pulses. The control module continues to enable the fuel pump relay as long as ignition reference pulses are detected. The control module disables the fuel pump relay within two seconds if ignition reference pulses cease to be detected and the ignition remains ON.

The Fuel System is a returnless on-demand design. The fuel pressure regulator is a part of the fuel sender assembly, eliminating the need for a return pipe from the engine. A returnless fuel system reduces the internal temperature of the fuel tank by not returning hot fuel from the engine to the fuel tank. Reducing the internal temperature of the fuel tank results in lower evaporative emissions.

The fuel tank stores the fuel supply. An electric turbine style fuel pump attaches to the fuel sender assembly inside the fuel tank. The fuel pump supplies high pressure fuel through the fuel filter and the fuel feed pipe to the fuel injection system. The fuel pump provides fuel at a higher rate of flow than is needed by the fuel injection system. The fuel pump also supplies fuel to a venturi pump located on the bottom of the fuel sender assembly. The function of the venturi pump is to fill the fuel sender assembly reservoir. The fuel pressure regulator, a part of the fuel sender assembly, maintains the correct fuel pressure to the fuel injection system. The fuel pump and sender assembly contains a reverse flow check valve. The check valve and the fuel pressure regulator maintain fuel pressure in the fuel feed pipe and the fuel rail in order to prevent long cranking times.

Step​
Action​
Values​
Yes​
No​
Schematic Reference: Fuel Hose/Pipes Routing Diagram
1​
Did you perform the Diagnostic System Check - Vehicle?​
--​
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information​
2​
Important: Inspect the fuel system for external leaks before proceeding with this diagnostic.
  1. Turn ON the ignition, with the engine OFF.
  2. Command the fuel pump relay ON with a scan tool.
Does the fuel pump operate?​
--​
Go to Step 3
3​
Important: Verify that adequate fuel is in the fuel tank before proceeding with this diagnostic.
  1. Turn OFF the ignition.
  2. Turn OFF all accessories.

  3. Caution

    Wrap a shop towel around the fuel pressure connection in order to reduce the risk of fire and personal injury. The towel will absorb any fuel leakage that occurs during the connection of the fuel pressure gage. Place the towel in an approved container when the connection of the fuel pressure gage is complete.

  4. Install a fuel pressure gage. Refer to Fuel Pressure Gage Installation and Removal .
  5. Turn ON the ignition, with the engine OFF.
  6. Important:
    The fuel pump relay may need to be commanded ON a few times in order to obtain the highest possible fuel pressure.
    DO NOT start the engine.

  7. Command the fuel pump relay ON with a scan tool.
  8. Observe the fuel pressure gage with the fuel pump commanded ON.
Is the fuel pressure within the specified range?​
385-425 kPa (55-62 psi)
VIN Z : 335-375 kPa (48-54 psi)​
Go to Step 4
Go to Step 8
4​
Important: The fuel pressure may vary slightly when the fuel pump stops operating. After the fuel pump stops operating, the fuel pressure should stabilize and remain constant.
Monitor the fuel pressure gage for 1 minute.
Does the fuel pressure decrease by more than the specified value?​
34 kPa (5 psi)​
Go to Step 7
Go to Step 5
5​
  1. Relieve the fuel pressure to the first specified value.
  2. Monitor the fuel pressure gage for 5 minutes.
Does the fuel pressure decrease by more than the second specified value?​
69 kPa (10 psi)
14 kPa (2 psi)​
Go to Step 12
Go to Step 6
6​
  1. Operate the vehicle within the conditions to reproduce the original symptoms.
  2. Monitor the O2 and the Fuel Trim parameters with a scan tool.
Does the scan tool parameters indicate a lean condition?​
--​
Go to Step 9
7​
  1. Turn OFF the ignition.
  2. Relieve the fuel pressure. Refer to Fuel Pressure Relief Procedure .
  3. Disconnect the chassis fuel hose from the engine compartment fuel pipe. Refer to Quick Connect Fitting(s) Service (Metal Collar) .
  4. Install the J 37287 Fuel Line Shut-off Adapter between the chassis fuel hose and the engine compartment fuel pipe.
  5. Open the valve on the fuel pipe shut-off adapter.
  6. Turn ON the ignition, with the engine OFF.
  7. Command the fuel pump relay ON with a scan tool.
  8. Bleed the air from the fuel pressure gage.
  9. Command the fuel pump relay ON and then OFF with a scan tool.
  10. Close the fuel feed pipe shut-off valve.
  11. Monitor the fuel pressure gage for 1 minute.
Does the fuel pressure remain constant?​
--​
Go to Step 12
Go to Step 11
8​
Is the fuel pressure more than the specified value?​
427 kPa (62 psi)
VIN Z: 375 kPa (54 psi)​
Go to Step 12
Go to Step 9
9​
Inspect the fuel feed pipe for a restriction.
Did you find and correct the condition?​
--​
Go to Step 13
Go to Step 10
10​
Inspect the harness connectors and the ground circuits of the fuel pump for poor connections. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?​
--​
Go to Step 13
Go to Step 12
11​
  1. Turn OFF the ignition.
  2. Raise the fuel rail, with the fuel lines connected. Refer to Fuel Rail Assembly Replacement .
  3. Turn ON the ignition, with the engine OFF.
  4. Command the fuel pump relay ON with a scan tool.
  5. Replace any leaking fuel injectors. Refer to Fuel Injector Replacement .
Did you complete the replacement?​
--​
Go to Step 13
--​
12​
Replace the fuel sender. Refer to Fuel Sender Assembly Replacement .
Did you complete the replacement?​
--​
Go to Step 13
--​
13​
Operate the system in order to verify the repair.
Did you correct the condition?​
--​
System OK​
Go to Step 3

Document ID# 1400167
2005 Chevrolet Avalanche - 4WD
 
Thanks! I'm sure this will come in handy in the future if not at the moment.

Quick question that I'm honestly afraid to ask:
What if I turned the crankshaft over when the timing chain was off? The new timing marks are lined up just as they're supposed to be, but are they still wrong because things were moved independently?

It's all reassembled so I'm really hating to ask that...
 
Thanks! I'm sure this will come in handy in the future if not at the moment.

Quick question that I'm honestly afraid to ask:
What if I turned the crankshaft over when the timing chain was off? The new timing marks are lined up just as they're supposed to be, but are they still wrong because things were moved independently?

It's all reassembled so I'm really hating to ask that...

Welllllll, generally not a good thing to do. You could damage pistons and/or valves (pistons are moving while valves are not = damage to one or both if hit hard enough). Did you rotate gently by hand or actually turn the starter?

As for the timing, without the cam turning (no timing chain attached), I would think that you would need to rotate one full revolution to get back where you started else you will be out of time (wrong bank of pistons at tdc). Maybe someone else will weigh in if I'm wrong.

I think that you would be okay timing wise if you rotated one (or more) full revolution (360 degrees) and have the alignment marks properly aligned.
 
Battery was disconnected so just by hand. I seem to recall doing so before I got to reassembling everything but for some reason i cannot recall. I did have to rotate the crankshaft one full rotation to get the timing marks lined up just right as it seemed slightly off when I took it apart, also there was just enough tension in the counterclockwise direction that the cam bolts (there were 3) wanted to cross thread. I put the old balancer bolt in and turned it with my breaker bar.

I just really don't want to open it up again. I'll accept a fuel pump failure or anything else if I don't have to lose all my fresh coolant and oil, or risk damaging my new gaskets. Not to mention the time. I'm already way past the expected time due to various issues.
 
what is fuel pressure at rail?
 
timing chain marks are based on #1 piston @ Top Dead Center.

Was it there when you aligned the marks?
 
timing chain marks are based on #1 piston @ Top Dead Center.

Was it there when you aligned the marks?
Thinking about this, and I'm likely missing something, I'm not sure how I could have messed anything up since there is a keyway on the crank and "post" on the cam. There's only one way to put those on. Unless it takes 2 full rotations to bring everything back into the same position?
 
Ok, just tested to see if it's my battery and unless the jump pack I got isn't working (first time using it) that's not the issue. I had my scan tool hooked up as it tried turning over and I've got a new code: U1000.

When I hooked my negative cable back up it sparked and set off my car alarm, twice actually because it startled me so it lost connecting for a second. Maybe something shorted?
 
2 Crank RPMS for every 1 cam rpm.

So yeah it is possible to mess it up.

Also, pretty sure GM likes it @ TDC at end of compression stroke.
 
2 Crank RPMS for every 1 cam rpm.

So yeah it is possible to mess it up.

Also, pretty sure GM likes it @ TDC at end of compression stroke.
Crap

Would I be correct in thinking that if the crank timing mark was at 12 o'clock and the cam was also at 12 o'clock I would need to take the cam and rotate it 180° to fix my dumb mistake?
 
Last edited:
All I know is cam timing is the one thing that makes my head hurt and I find and read the instructions.

You should be able to check by removing plug#1 and turn crank until you see it come up to timing mark and see piston in plug hole with one of those little cameras.

then remove valve cover and check where rockers are for #1.

Then rotate crank and watch - From TDC and downward nothing should happen as we are on POWER stroke.
Once it gets near or after bottom and starts coming up then EXHAUST opens
Then INTAKE will open and now the cam gurus get their money here by the timing and overlap of when intake opens versus when Exhaust closed.
But by the time the piston goes all the way down and starts back up intake should be closed for COMPRESSION

I have no idea if cam timing is your issue...seems an error code would come up or something maybe?

Maybe time to find a mechanic and invite him over for some beers?
 
Found this in ls1lt1.com. Helped me to understand so I'm posting it for anyone who could also benefit from it:

"Each time the #1 piston is a top dead center, the dot on the crank gear will be at the 12 o'clock position. BUT the cam gear dot will be at one of two different positions.

The cam turns at half the speed of the crank. For each 360 degree turn of the crank gear, the cam gear only turns 180 degrees.

If the CAMSHAFT GEAR DOT is at the 6 o'clock position, and the crank gear dot is at 12 o'clock, then the #1 piston will be on the Exhaust Stroke. It's only when both the crank gear dot and the camshaft gear dot are at the 12 o'clock position that the #1 piston is on the Compression stroke"
 
I thought that you said you turned the crank by hand with the timing chain OFF which would mean that the cam did not turn. If that was indeed what you did, which was the scenario I addressed with my one full turn remark, then you only needed one full revolution of the crank to get pistons back to where you started.

If the cam was attached then, as others stated, you need two full crank revolutions as you now know.
 
Last edited:
You guys are making this way too complicated...

TDC for the number one piston happens twice during each 4 stroke cycle, once at top of the compression stroke and then again at the top of the exhaust stroke. If the cam was not rotated, then lining up the timing chain marks should be in sync. The computer doesn't know if it's the firing stroke or the exhaust stroke without the cam sensor telling where it is in the cycle..

The question is did you line them up with both of them together where they meet in the middle or with both of them straight up???
 
Last edited:
You guys are making this way too complicated...

TDC for the number one piston happens twice during each 4 stroke cycle, once at top of the compression stroke and then again at the top of the exhaust stroke. If the cam was not rotated, then lining up the timing chain marks should be in sync. The computer doesn't know if it's the firing stroke or the exhaust stroke without the cam sensor telling where it is in the cycle..

The question is did you line them up with both of them together where they meet in the middle or with both of them straight up???
They were both pointed at each other, crank at 12 o'clock cam at 6 o'clock. I think what happened is that I rotated them both separately with the chain off (don't ask me why, i had a reason at the time that i cannot remember) and upon reinstalling the cam should have been at 12 rather than 6. I was thinking all that mattered was the timing marks, but it's obvious upon retrospect that the 2 different size gears spin at different speeds so there would be more to it.

Unless someone else has info that points me in another direction I'm going to take the timing cover off this week and reposition the cam then check to be sure the mark on the cam sprocket is where it's supposed to be on the Compression stroke. Just going to do the wad of shop towel in the spark plug hole trick to find compression.

Did get my fuel pressure gauge so could test that first, but pretty sure I messed up the timing.
 
Last edited:
Back
Top