I've been having a problem with my 2wd 2004 Tahoe LS for quite a while now. Anytime I go to start it I have to shift down to drive then back up to park otherwise it won't even attempt to start. I'm sure it's some sort of sensor somewhere but I can't find anyone else who has had this issue. If any of you have had this issue in the past please let me know what to do, I'm lost when it comes to electrical stuff. Thanks

 

Sounds like your neutral safety switch is going out. or the linkage is loose and needs new bushings.

 

I second this possible cause.

 

Service Information
2004 Chevrolet Tahoe - 2WD | Avalanche, Escalade, Suburban, Tahoe, Yukon (VIN C/K) Service Manual | Document ID: 825193
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Park/Neutral Position Switch Adjustment
Important:

• The following procedure is for vehicles that have not had the park/neutral position (PNP) switch removed or replaced. If the switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the proper adjustment procedure.

• Apply the park brake.

• The engine must start in the park (P) or neutral (N) positions only.

• Check the PNP switch for proper operation. If adjustment is required, proceed as follows:


Place the shift lever in the neutral (N) position.
With an assistant in the drivers seat, raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .
Loosen the PNP switch bolts.
With the vehicle in neutral (N), rotate the PNP switch while the assistant attempts to start the engine.
Following a successful start, turn the engine OFF.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Tighten the PNP switch bolts.
Tighten
Tighten the bolts to 25 N·m (18 lb ft).

Lower the vehicle.
Check the PNP switch for proper operation. The engine must start in the park (P) or neutral (N) positions only.
Replace the PNP switch if proper operation can not be achieved. Refer to Park/Neutral Position Switch Replacement .
© 2015 General Motors Corporation. All rights reserved.

 

Thanks guys, it was the neutral safety switch. I've never had a problem with one of those before but it fires right up every time now.