# timing chain issue



## joseph6055 (Nov 30, 2014)

I removed the top timing chain of my 2001 nissan altima gle. It has two overhead cams. I reinstalled the new chain and tensioner. I re aligned all the paint marks on the sprockets with the New chain. assembled everything and try to start the car. It sounds like it's just turning the engine and has a sound like Its trying to start but won't. It doesn't even try to crank over.what could be the issue?


----------



## rogoman (Dec 16, 2004)

Before disassembling anything on the chain assembly, did you set the No.1 piston at TDC on its compression stroke? At this point do not attempt to turn the engine until the chain is installed.

When you say "it doesn't even try to crank over", does that mean it's locked. If so, then the chain timing is most likely incorrect.

If the engine does crank over freely but fails to start, you may have a problem with ignition or fuel delivery. Make sure all the harness connectors are plugged in and that the engine grounds are secure. You might want to perform an ECU code readout with a scan tool to see if there are any fault codes set.


----------



## joseph6055 (Nov 30, 2014)

After I took it all apart I did find tdc again on the crank and it lines up on the distributor. I then lined up the cams to the 12 o'clock positions on the key which lined the chain up perfectly with the lower sprocket on all the marks. It turns but doesn't sound like it's going to fire.


----------



## smj999smj (Jan 1, 2006)

Did you replace the upper chain because the chain jumped? If so, you may have bent valves. This would show by doing a compression test.


----------



## joseph6055 (Nov 30, 2014)

Yes I replaced the upper chain. Wouldn't the engine at least attempt to fire? I don't hear any knocking or noise from the engine when it's cranking.


----------



## joseph6055 (Nov 30, 2014)

Update. I took everything off and made sure it was aligned. It was aligned as it should have been. However, after putting everything back, I turned to start the car and pressed the gas then the cover to the filter in the engine came popping off. Does this mean the valves are screwed and it's causing that much pressure?


----------



## smj999smj (Jan 1, 2006)

That means it backfired. It could be a timing issue or a valve issue. I would recommend a compression test.


----------



## rogoman (Dec 16, 2004)

joseph6055 said:


> Update. I took everything off and made sure it was aligned. It was aligned as it should have been. However, after putting everything back, I turned to start the car and pressed the gas then the cover to the filter in the engine came popping off. Does this mean the valves are screwed and it's causing that much pressure?


Since you had to remove the valve cover, the spark plug wires also had to be removed. It's possible that upon reassembly the firing order may be incorrect (wrong wire for a given cylinder). That could cause a back-fire.


----------



## joseph6055 (Nov 30, 2014)

I checked the wires about 20 times. Made sure they were all correct. I am also hearing a buzzing sound underneath the distributor with the ignition switch on. I don't think It did that before


----------



## rogoman (Dec 16, 2004)

Apparently you have more issues then just a chain replacement. Go over all your electrical connections, in particular the grounds; you may have missed something during re-assembly.

Before going any further, perform that compression test on ALL cylinders; the readings should be: standard - 178 psi, minimum - 149 psi. If you have any bent valves, there will be a lot more dis-assembly so at this point don't worry just yet about any electrical issues.


----------



## joseph6055 (Nov 30, 2014)

I know. I wonder if they bent when the old chain crapped out. I will do a compression and check all The electrical but If checked everything over and over again


----------

