How to fix the trailblazer 2004 4.2l engine timing chain

What size engine ? V-6 , has timing chain an gears . To check it you have to take front of engine apart .

No.....our timing chains are bullet proof, not a common problem for the chains to go out.

whenever working on an engine with overhead cams, the timing chain will be removed when replacing heads ,then reinstalled when heads are installed and timing must be performed to insyre engine runs properly or you might run into some seriuos engine damage.now if the chain came off after engine was reassembled then i would believe something was not tightened or chain was not checked for damege or wear when it was off.

Absolutely not. Timing chain is not connected to the heads on a Trailblazer.

No not really. Unless there is a major failure. These are bad for the chain guides.. Made of plastic and wearout...Not an easy fix..You have to tear apart the top of the engine and the bottom of the engine to fix it. Takes me about 8 hours, I've done a few of them.

Check the timing chain. Some times the chain will shift with worn teeth and get out of synch. This will cause the engine to lose power and back fire. Sometimes with a flame through the carb. I did that one once. Easy fix if it is the problem.

You didn't mention the engine size so I gave you the most common, the 4.2 lter engine. I hope it's the right one for you. Below are the timing marks per ALLDATA as well as information on removing the cover if you need it. I hope this helps you and that it's the right engine. good luck.

Hello shreddingdas: My name is Roger and I will help you. The motor in your trailblazer whether it is the 5.4 or 4.2 engine. Will ot have a timing belt. They both use a timing chain.They need not be replaced at any particular interval. SHould you need further help or further information please just ask. Please rate the answer. Thank You for using Fix Ya. Roger

The vehicle uses timing chains, which should last the lifetime of the engine. In rare cases, servicing is needed if the timing chain guides encounter excessive wear. Symptoms include rattling noises from the timing cover. Hopefully this helps!!

The timing chain on the Trailblazer 4.2 L is a metal chain. Unlike plastic timing belts that require replacement at certain mileage, this metal chain should be good for the life of the engine.