ve ss l98 engine noise under slight load

[geoffdegs]

[video]https://youtu.be/vAEOgI8nZyE[/video]

Hello, I have a noise under slight load cant pinpoint where it is coming from. Had a few mechanics look at it thought it was the balancer but just had that replaced old one was stuffed anyway.. I posted a video of the noise revving slightly under load then backing it off. took all the belts off still made the same noise. checked the cats appears no rattle checked all the heat shielding all ok. I run 98 it does sound like a ping but isn't. very hard to pin point doing my head in lol

If anyone can help It would be very appreciated

 

[Capsule]

Does the noise stop if you remove the dipstick? I've read this kind of noise is sometimes caused by the PCV system

 

[geoffdegs]

Re Ve ss l98 engine noise

Does the noise stops if you remove the dipstick? I've read this kind of noise is sometimes caused by the PCV system

Hi Thanks for the reply. I haven't tried but I will thankyou.

 

[928S]

If can believe it I came to post the same problem. You will also have a slight stumble under light load. The engine rattling occurs under load slightly higher up the rev range. You will also have rattling when you back off in certain (low) rpm ranges. The car will lose some power too. Mine doesn't make the noise when completely cold for the first 30 seconds. I suspect it warms up and goes off the cold start circuit indicating a change of mixture. That is the mixture is leaner. The car will also feel more powerful when it is not having this problem for the first 30 seconds of driving. I have had three mechanics look at it. (I am a retired mechanic) It went to the dealer first, then their LPG specialist. The car has LPG but it does this on both fuels. It also went to my LPG installer who also ran live data. It shows no faults.

I believe the engine has a random spark advance at lower rpms. Upto a maximum rpm limit of approx 1,800 rpm. It will rattle under no load at 1050 to 1,100 rpm. I decided (as I am keeping the car and it has been overly maintained) that I would change the crank angle sensor and the knock sensors. It didn't help but the car seems to start better now. My car has 160,000 on it and we bought it when it had 15,000 kms on it and it is a WM Caprice. I was going to keep changing sensors till I fixed it but that is not the best way to go about it however I would like to refresh a certain amount of sensors just for reliability anyway. We know through live data the (silver) throttle body is a bit lazy along with the oil pressure sender.

Surely somebody else has had this problem and solved it????

 

[2INIL8]

Its detonation,the actual fix is to have the tune fixed.
Try a colder range spark plug like the ngk tr6 it will take more timing
than with a standard 5 heat range spark plug.
No changing of sensors or anything will fix this issue.
My brand new vf1 did the same ,knock going up hill 1000-1400 rpm with load.
Fix was to pull timing and go to a colder plug now it doesn't do it.
Stock exhaust systems are restrictive and make the problem a lot worse too.
If you log the car with hp tuners or efi live you will see knock events (kr).

 

[928S]

Thanks for the response, I accept what you are saying could be the issue and will pull the plugs today and seek replacement. Can you confirm the noise in the video is exactly the same as yours? The plugs were changed about 30,000 kms ago and there no problem at the time, it is has just come on now, is it carbon build up in the chamber and I should try some fuel additive cleaner? Cheers.

Its detonation,the actual fix is to have the tune fixed.
Try a colder range spark plug like the ngk tr6 it will take more timing
than with a standard 5 heat range spark plug.
No changing of sensors or anything will fix this issue.
My brand new vf1 did the same ,knock going up hill 1000-1400 rpm with load.
Fix was to pull timing and go to a colder plug now it doesn't do it.
Stock exhaust systems are restrictive and make the problem a lot worse too.
If you log the car with hp tuners or efi live you will see knock events (kr).

 

[928S]

Well I just pulled the plugs and it is running NGK TR6 plugs already. The gapping on them looks a bit large and I am now checking for the factory specs as they are larger than what has been suppled by NGK which is 1.0 mm. I did buy some fuel system and combustion chamber cleaner also will at it. That has been added to a fresh tank of 98 octane.

 

[geoffdegs]

Re Ve ss l98 engine noise

Well I just pulled the plugs and it is running NGK TR6 plugs already. The gapping on them looks a bit large and I am now checking for the factory specs as they are larger than what has been suppled by NGK which is 1.0 mm. I did buy some fuel system and combustion chamber cleaner also will at it. That has been added to a fresh tank of 98 octane.

Thanks for your reply.
Yesterday I had the harmonic balancer replaced as it was stuffed rubber come out of it etc wasn't that wobbly though.

It has made a massive improvement to the cars performance in the low rev range under load. Where it used to stumble hesitate around the 1000 to 1200 rpm mark it doesn't anymore. I can still hear the noise in the low rev range and posted the video yesterday with the car in drive and slight acceleration brake on. The noise came in at 1000 rpm. not as loud as previously.

I did put new plugs in at 90k done 105 now. Didn't notice any noises when I replaced them. I put in ac delco iridium 12621258 41-110 supposed to be a direct replacement.

I will change to the nkg tr6 to see if that makes a difference and book it in for a tune/software update as when I checked the version it is the original from 2007.

Thanks for all your help and I hope this fixes your issue as well 928s

 

[928S]

Thanks for your reply.
Yesterday I had the harmonic balancer replaced as it was stuffed rubber come out of it etc wasn't that wobbly though.

It has made a massive improvement to the cars performance in the low rev range under load. Where it used to stumble hesitate around the 1000 to 1200 rpm mark it doesn't anymore. I can still hear the noise in the low rev range and posted the video yesterday with the car in drive and slight acceleration brake on. The noise came in at 1000 rpm. not as loud as previously.

I did put new plugs in at 90k done 105 now. Didn't notice any noises when I replaced them. I put in ac delco iridium 12621258 41-110 supposed to be a direct replacement.

I will change to the nkg tr6 to see if that makes a difference and book it in for a tune/software update as when I checked the version it is the original from 2007.

Thanks for all your help and I hope this fixes your issue as well 928s

I did reply to your other thread but what I have to add is that my harmonic balancer is also pretty crook. I didn't think this could cause such a noise? So that is very interesting. If I can ask what was the cost of the balancer replacement? Don't bother with the NGKs, I just changed them again, no benefit All the best!

 

[geoffdegs]

I didn't believe it as well but definitely a huge improvement I got a power bond got it from sprint auto my father in law works there got it for 230 bucks (about the same as on ebay). Got a new bolt from holden $25 and a new oil seal about 50 from holden but could get these cheaper on ebay or similar. Got a mechanic to do was hard to get off and on I didn't have the right puller he charged 140 bucks. He said the seal was hardened so it was best it was replaced at the same time. As I said the noise is still there a little but can hardly hear it and doesn't effect the car like it used to.

thanks for the info on the plugs