Oh Boy

2013 Grand Sport, bought new and babied for 26k miles. I changed the oil yesterday (dry sump) like I always do every year at this time. I only put 1000 miles since the last one. Always Mobil1. That's a little background. I have been using the car these two days and noticed when I was parking it today a ticking or whatever sound. I opened the hood to listen to this. At first I thought it might be the compressor but on or of makes no difference (doesn't mean it can't be the clutch) However the sound seems to be coming from all over consistently, each side of the motor, each wheel well and underneath (from bending down and listening). Tell me I'm not screwed, but if it is I have to accept it.

airmed2

Wouldn't a 'blown' motor throw a code?

ShagVette

Torque tube?

Corvette_Ed

This. If the motor was blown there'd be several codes thrown.

Landru

Pretty loud, possibly a bad/stuck lifter?
If lifter hope it didn't wipeout a cam lobe or 2.

rkj427

oil pressure reading is:_____________________ does it increase in frequency with rpm increase:__________________

you may want to remove plug wires one at a time to see if you may be able to isolate it to a particular cylinder.................. use caution when doing this, use tools to remove wires which are insulated so you don't get voltage through you...........

Turbo6TA

That don't sound like anything internal inside the engine.

Get under the car and look at the harmonic balancer when it's not running ... Is the front of the balancer chewed up from rubbing up against the steering rack (that sets right in front of it) ?

Does the rear of the balancer look like it's been rubbing up against the timing chain cover ?
_________________________________

If that's ok ... remove the serpentine belt (the long one .. not the short one that turns the AC compressor)

Start it up and let it idle for about 15 seconds without the belt (won't hurt anything) .... Does that noise go away then ?

If the noise then goes away, you have a problem with one of these:

1. Water pump
2. Alternator
3. Power Steering Pump
4. Belt Tensioner
5. One of the 2 Idler Pulleys

.

TCW

Sounds like your harmonic balancer is rubbing the steering rack.

Tom

Bruze

Yes, that's the crucial thing to know. Sounds like a belt chirp or something related to that.

Just off the cuff, the odds of this being a "blown" motor are somewhere between Slim and none, and I saw Slim headin' outta town at high noon.

To me, a "blown" motor is one that doesn't run because it broke a rod, dropped a valve, etc.

The OP mentioned clutch (?) but if it was, the sound would likely change when you push the pedal in.

subfloor@centurytrans

Uh...no, not true at all.

FatsWaller

I watched the video, and I don't see any HB wobble. The frequency of the sound is about 4 or 5 beats per second, which gives us 240 to 300 beats per minute. The idle speed is at least double that, so if the HB was rubbing, you'd expect the sound to occur with each revolution. On the other hand, the valve train speed per lifter is would be 300 per minute at an idle speed of 600 rpm, so it could be a lifter.

Chevyrelic

Have you tried using one of the cheap HF engine stethoscopes to pinpoint where the noise originates?

Corvette_Ed

Then I'll believe when I see it, and after many years and even more blown engines, I still have yet to see it.

Andysherman

Yeah, it sounds more "chirpy" to my ears, a pulley or belt may be the culprit, water pump, idler pulley, etc... so nothing really major. Please let us know what you find.

FatsWaller

Just recalled where I heard a similar sound and it was the serp belt on my Caddy. It had reached end-of-life and it was a relatively cheap fix.

Garry in AZ

Lifter or a loose spark plug. Check and make sure all the plugs are tightened properly. If they are, then I'd be looking at lifters. Sounds like a loose plug to me. I had a 78 Trans Am that a plug came loose in... sounded just like that.

subfloor@centurytrans

Exactly what codes do you think you'll see??? Unfortunately there simply isn't a P0xxx code (as an example) that equates to a blown engine.

With a catastrophic failure (like throwing a rod through the side of the block) the motor simply stops spinning. With something less harsh (like a spun main or rod bearing) it'll get noisy and the oil pressure would just start dropping as the motor got hotter. Even if you kept on running it with a bad bearing and it completely seized, you simply wouldn't be able to turn it over anymore.

I had three engines let go on me over the last 18 months with spun bearings because of oiling issues (turns out drag racing doesn't play nice with an LS7 converted to wet sump) and there were no codes thrown. I've even dropped a valve twice while doing 130MPH at the track and had a rod come through the side of the block in both cases and once again, there were no codes.

d.medic

My last Vette still dynoed in the 500 plus rwhp range with a chunk missing in number 7 piston. No codes.

torquetube

Try everything that's been suggested, in order of difficulty:

Confirm the plugs are tight and check for exhaust leaks. Pull the belts to rule out the accessories. Remove the valve covers and inspect.

Hopefully it's one of those. A loose rocker arm if you're lucky.

Now I'll tell you what it sounds like to me: a bad valve lifter roller that's grinding a groove into one of your cam lobes.

Oh Boy

Oil pressure is normal, I don't think I revved it out of fear.

The HB is running dead straight.

I sure as hell hope it is. No I said the clutch on the compressor.

No not yet.

I will definitely post back, you guys are always kind enough to respond and I would never start a thread with out posting the results.

I will definitely check.