help have engine knock.

**twentyocho** · 02-19-2013

Guys have a knock which i thought might be my engine taking a crap but no metal or coolant in oil. No loss of coolant. No oil burning. Cant figure it out. Saw a video on youtube with car making same sound. Guy said oil sending unit went bad. This make sense? If so where's it located and is it hard to replace? Thnx for any help.

**Nighthwk12** · 02-19-2013

which side of the engine is it coming from? Do you have oil pressure? Might be your flexplate bolts

**twentyocho** · 02-19-2013

Cant pin point it but will check for oil press. asap. Any way to do this fast?

**Nighthwk12** · 02-19-2013

You have an oil pressure gauge on your dash? The oil pressure sending unit is right above the oil filter. You can hook up a manual gauge there to check pressure.
Also an exhaust leak could have a knock type sound to it

**Scottydoggs** · 02-19-2013

you can rent or buy a oil pressure test gauge you take the low oil pressure sensor out, and screw the hose from the gauge into where the sensor was, then start the engine up. then read the gauge. at a cold start you want to see close to 50 psi or higher, warmed up at idle you want to see at least 19 or higher psi.

**Scottydoggs** · 02-19-2013

oh, and the pressure sensor in just past the oil filter on its housing, you'll want to take the pass side tire off to get to it.

**GTPpower** · 02-19-2013

Pull your spark plugs out and make sure none are smashed.

**BillBoost37** · 02-19-2013

When you spin a bearing or get rod knock, it isn't common to see coolant or oil leaking/mixing/missing. None of that is compromised. Possible crap in the oil, yes. Not easy to see on the dipstick all the time though.

**twentyocho** · 02-19-2013

Guys im gettin a video up as we speak. just got back so probly not messin with it today but will for sure tomorrow.. From what your tellin me Billboost im not gettin a good feeling. The more i try to listen to it the more I think its coming from the inside of the engine. This sucks I was gettin really attached to this car. Had just ordered new headlights for it dammit..

**Schwuppes** · 02-19-2013

could be harmonic balancer mate?

**twentyocho** · 02-19-2013

Ok fellas ima try to get vid up.. Here goes..

<iframe width="560" height="315" src="2000 Pontiac Grand Prix GTP Mystery knock - YouTube" frameborder="0" allowfullscreen></iframe>

**dsmuts** · 02-19-2013

Doesn't sound good whatever it is. To me it sounds internal.

**Scottydoggs** · 02-19-2013

make another vid, and rev the engine to say 2500 to 3000 rpm, hold it there for a few seconds then let the gas go back to idle, like just let it drop back.

the vid you posted kinda sounds like a broken spring, or valve train, "maybe". the 2 nd vid will clear that up for us.

**FordMan77** · 02-19-2013

That really doesn't sound like a rod to me. Have you tried removing the S/C belt and starting it to see if the sound went away, or maybe both belts? If it's not a pulley then could be a rocker.

**twentyocho** · 02-19-2013

Guys i really appreciate the responses. Im gonna get a second vid up Scotty and follow your instructions. I will say it seems louder at top than bottom from what i can here. Anyways ill try to have tha vid up early in the AM.. Again i do appreciate any and all feedback. You guys have a great night tonight and hopefully tomorrow that vid will remind someone of something familiar and i can get it fixed.. I will say the wife isnt too happy with the thought of me sinkin money on it considering its my "work" car lol.. But God willing and its within reason i wanna get this car up and running again..

**MoarkatsINmuhtrailer** · 02-19-2013

if the sound goes away with when you raise the rpms it is probably the flexplate. you could also get under it and take the inspection cover off and shine a light up on the flexplate to see if you can see if its broken. it does not sound like a spun bearing/rod.

**twentyocho** · 02-20-2013

Ok guys got a vid of it while idling then revd up a few times. Revd it up to 2500 then idled then 3000 then idle then 2500 to 3000 then off.. Not thinking its the flexplate as knock is pretty consistent.. Anyways here's the vid as promised hopefully it sheds some new light on the situation... Once again thnx again for all the help fellas..

<iframe width="560" height="315" src="2000 GTP Engine Knock - YouTube" frameborder="0" allowfullscreen></iframe>

**Scottydoggs** · 02-20-2013

still sounds valve train related to me. id pop the valve covers off and have peek at whats going on there.

could be a broken spring or something easy to deal with.

**BillBoost37** · 02-20-2013

Listening right now.

It's very consistent, very light. If you start up a bad bearing motor and rev quick to say 2500, just a quick throttle blip and let right off, there's typically a distinct banging on let off. Your vid it's consistent. More like one cylinder not firing.

Do you have a scanner of any sort to look for misfires on one clylinder? Did you do any work to it recently? Sounds too nice and consistent.