2000 GMC Sierra Loud Ticking

[Bradamoki]

Hello I have a 2000 GMC Sierra 5.3 4x4, it has been sitting for 6 months. First thing I did was change the oil, next I drained the old gas and put new gas in. The truck would crank but not turn over. I replaced the fuel filter, and replaced the fuel regulator. Prior to replacing the fuel regulator I had no fuel pressure, gas was leaking through the diaphragm of the regulator into the intake manifold. Once I replaced the above items fuel pressure was up to 50psi with key in start position. The truck fired right up no problem but, there was a very loud ticking sound that sped up and got louder when I pushed on the gas. I immediately shut it off. I checked the oil and the dipstick smelled like gas. I drained the oil and there was a lot of gas mixed in with the new oil. I replaced the oil filter and filled it with new 5W-30 Mobile 1 high mileage synthetic oil. It fired right up again and the loud ticking sound was still there. Oil pressure was good I let it idle for a few minutes and the ticking got a little bit quieter but, still loud. Check engine light was on and the codes were P0300 and P0200. I hooked up a Noid light to each injectors wiring harness at idle and every one was firing. I removed the fuel injectors and cleaned them, did OHM test on each one and all of them had consistent readings. I do not know what else to do from here? Any help, direction, or advice would be greatly appreciated. Thank you for taking the time to read this.

My truck has 245,000 miles on the original engine.

 

[Jsdirt]

We've got a terminology barrier here. If it cranked, it's "turning over". I think what you meant to say is it was a "crank, NO START" prior, correct? Just want to make sure we're on the same page, since internet diags are difficult enough.

 

The P0300 (random, multiple cylinder miss) is probably intake gaskets given its age, mileage, and the fact it sat parked half a year. The P0200 indicates you've got some wiring issues related to the injectors. Probably just unplugging them and plugging them back in after your testing "fixed" that code, I would guess.

 

Oh and the tick was from gas dilution of the oil, as you found. You may have to do one or 2 more oil changes. And since you live in CA where it's warmer than most places, I'd run 10w-30 full synthetic in that. Will quiet it right down. I run it up here in MA, all winter long, too.

 

Edited May 26, 2021 by Jsdirt

[Bradamoki]

On 5/25/2021 at 5:25 PM, Jsdirt said:

We've got a terminology barrier here. If it cranked, it's "turning over". I think what you meant to say is it was a "crank, NO START" prior, correct? Just want to make sure we're on the same page, since internet diags are difficult enough.

 

The P0300 (random, multiple cylinder miss) is probably intake gaskets given its age, mileage, and the fact it sat parked half a year. The P0200 indicates you've got some wiring issues related to the injectors. Probably just unplugging them and plugging them back in after your testing "fixed" that code, I would guess.

 

Oh and the tick was from gas dilution of the oil, as you found. You may have to do one or 2 more oil changes. And since you live in CA where it's warmer than most places, I'd run 10w-30 full synthetic in that. Will quiet it right down. I run it up here in MA, all winter long, too.

 

 

[Bradamoki]

On 5/25/2021 at 5:25 PM, Jsdirt said:

We've got a terminology barrier here. If it cranked, it's "turning over". I think what you meant to say is it was a "crank, NO START" prior, correct? Just want to make sure we're on the same page, since internet diags are difficult enough.

 

The P0300 (random, multiple cylinder miss) is probably intake gaskets given its age, mileage, and the fact it sat parked half a year. The P0200 indicates you've got some wiring issues related to the injectors. Probably just unplugging them and plugging them back in after your testing "fixed" that code, I would guess.

 

Oh and the tick was from gas dilution of the oil, as you found. You may have to do one or 2 more oil changes. And since you live in CA where it's warmer than most places, I'd run 10w-30 full synthetic in that. Will quiet it right down. I run it up here in MA, all winter long, too.

 

Thank you very much for replying Jsdirt. Yes, you are correct it would crank but, no start prior. 

I picked up intake and valve cover gaskets yesterday. Right now I have the intake manifold off and the valve covers off. On the drivers side 2 of the valves are open, the pushrods are all the way up. The rocker arms for these are in an opposite position than all the rest. The are right next to each other but, are for different cylinders. Do you know how I can close them so all the rocker arms are in the same position? I really do appreciate your time. 

[Jsdirt]

I hope you checked the gaskets before buying them. That might not be your problem - it was just a suggestion. You've got to check these things before winging parts at it.

 

A squeeze bottle of water poured along the gasket area while it's idling will usually reveal any intake leaks, especially with a cold engine. If the leak is small, it can be hard to detect. Watching fuel trims on a scan tool while doing the test might reveal a smaller leak. 

 

As far as the rockers go, I just rotate the engine around and loosen the ones with no tension.