Jump to content
SAU Community

Recommended Posts

There is a link tht best describes the noise I am hearing from my car. I woul;d like to know if this is knock and also how is this possible? I just got forged pistons and I took it for a spirited drive for like 2 mins giving it a thrashing and i noticed a noise like this when I got back. Checked the oil level and it was extremely low. Could low oil level cause knock? Or is this noise something else? I just put in standard bore pistons there are not oversized or anything. So any help or suggestion will be greatly appreciated. Thanks!!!!!!!!! Just change everything man Fu#$ this is a disaster if anything is wrong. I just changed pistons, headgasket, oil pump, water pump,timing belt, main and con bearings, spark plugs. I mean it was suppose to be a complete service so how the hell could he have not put oil in it, sh*&. I mean the oil level was barely on the L mark and also something was burning, smoke was coming from in the engine bay not much, but it was and it was from the exhaust manifold/dump pipe/turbo area.

Edited by Daboss
Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/
Share on other sites

knocking (detonation) occurs when the engine is under load from too much timing typically

you don't get knocking (detonation) at idle so its not knocking

that sounds like bearing knocking - could be big end bearing?

dont know enough about engine mechnics but its not timing related knocking

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4077499
Share on other sites

yeah mate by the sounds of it you could have a noisey lifter. i don't think it sounds like a bottom end knock. as paul stated knocking or pinging as it is mostly refered to, happens more when the vehicle is under load. hope this sheds a bit of light.

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4077510
Share on other sites

when you say " little to no oil " where did the oil go? you may have caused more damage then i initially thought. if you have starved the bottom end of oil, it's possible that you have caused bottom end damaged. :D

When you say you have just done this work did you take it out of the workshop and give it hell? My advice would have been to avoid hard acceleration but to build up reasonable revs and then lift off alternately for a bit and not to give it stick for a few hundred Ks at least.

Was the work done by a professional? If so take it back immediately.

What was done to the bores - could the rings hit the lip around the top? If there was oil on the stick then you should be OK on that score. Sounds like you need to at least pull the head off and have a look before you do any more damage.

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4077724
Share on other sites

fried rings?

injector pulse?

noisy lifter?

my supra sounded like that and it was just injector pulse, you sure it wasnt like that b4 u went for a fang?

tow it back to the workshop to be safe and see what they say mate

for a rebuild why didnt they start with fresh bores and oversize is 20 thou?

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4077748
Share on other sites

Ok here is the results of my troubleshooting, I gave it an oil change, changed and regapped all the plugs. Now she runs ok I still her a slight miss at idle so i checked the timing with the tps unplugged and noticed it was fully advanced, so I put timing back to 15 and she ran great. I plugged the tps back in timing dropped to about 5 degrees and the miss came back with a slight knocking sound, took the tps off revs and timing advanced to 15 and the miss and knocking went away she ran great. Put the tps back on and well you can see the pattern. Now my question is what is causing the timing to retard and miss to come about when I plug the tps back in?

OHHH, and to answer your questions it was done by a workshop(don't know if I could call them "skyline professionals" as I am in the Bahamas but they know their stuff when it comes to machining cars) the blocked was bored to suit the new forgies.

I did give it a lil fang when I got it back wasn't a long period say for about thirty seconds a lil spirited drive and thats not all out just a quick boot in first and second probably got to 6000rpm didn't get to third. Before I fanged it about 300km were put on it no boost and no revving pass 3000.

It had about a gallon of oil in it when i changed so oil so tht one still is a mystery to me, when I look on the dipstick now I can't see a level but I know its full because I placed a gallon and half a quart of oil in there myself.

Thats not my car in the vid either was to work and it was the closest noise i could get to my car sound will try to get a vid together of my ar and the noise and palce it on here.

Thanks for all the great responses so far and I hope u can help my figure this out just this last prob and I am done, You Guys are great!!!!!!!!!!!!!!!!!1

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4079073
Share on other sites

thats weird to run it in with 300kms 3k rpm and NO boost?!

cant be right?

just take it back to the workshop dude..... hope they can/will recrify it for you

gallon and a half = 5.5 litres?

isnt that waaaay to much for a rb25?

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4079111
Share on other sites

thats weird to run it in with 300kms 3k rpm and NO boost?!

cant be right?

just take it back to the workshop dude..... hope they can/will recrify it for you

gallon and a half = 5.5 litres?

isnt that waaaay to much for a rb25?

No not a gallon and a half of oil. A gallon of oil and half a quart of oil. No I was just sayin tht to show it wasn't a str8 out the workshop flog. I just boosted it that one time after about 300kms of driving off boost.

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4079138
Share on other sites

id like to know the cause of this too. i have had a similar sound that occured 3 times only earlier in the year on and off only on super hot days (bahamas..lol) and only after i did an advance driver course with heaps of spinning around. sounded like a deisel motor but would go away if i let it sit and cool for 20min or so. hasnt done it since. will have to see when it starts to heat up again.

Link to comment
https://www.sau.com.au/forums/topic/232306-is-this-knock/#findComment-4079461
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Actually, that's not entirely true. It's also the same motor in the 1st gen Nissan Cube but they're rare as hen's teeth.  
    • Yeah it is always worth testing and balancing actuators out of the box, just set the pressure regulator on a compressor very low (eg 5 psi) and increase it slowly to see when they both move.....unfortunately while you may be able to adjust the length of the actuator rod to minimise any difference, the actual pressure they move from is not adjustable so you need a well matched pair. And yes, the VCAM is probably contributing; the earlier in the rev range they come on boost and the slower the revs build (I think your demo was in 5th), the more you notice it.  Driving at WOT through 1st, 2nd, 3rd etc you will probably never hear it as any shuffling starts and is over super quickly
    • oh they were with that motor, you need to remove the engine to change the spark plugs (don't have to, but it does make it easier)
    • I certainly fall into the annoyed camp, but glad to hear that if it's happening at low boost then I'm not likely going to blow a turbo and end up with metal shards in my oil. Just feels like it prevents me from really driving it without hesitation and "peak" performance. Wonder if it's the VCAM, it did an impressive job of shifting the torque curve and faster spool, but maybe now it's "too fast" and there's too much air for how open the throttle is.  Based on some other threads, will also do some reading on synchronizing the actuators. They are the default actuators that come on the Garrett's and I would think they would be set the same coming from the factory, but if the turbos don't actually work exactly the same way at the same time as previously mentioned, it would be worth making sure the actuators are actuating together properly
    • I went down this rabbit hole before, ended up sourcing a motor from the UK (I'm in Japan) which also didn't function correctly. With the original motor, I disassembled it and reassembled it and it works somewhat, sometimes. What I could deduce from all my screwing around is that there is calibration of the gears on the inside of the motor and two ramps on the main gear which activate switches that operate the motor and move the sunroof either to retract into the roof or tilt. Where I got stuck was that, it seemed in my case that one or both of the switches that are activated by the ramp on the gear did not always activate and thus the motor did not move, causing it to sometimes not retract or tilt (apologies, I've forgotten which way it didn't work.).  Of course this part is discontinued at Nissan now, it's the same part in the S15 but no other models. I also contacted the manufacturer of the component for schematics - forgot the name, they're based in Gifu - but they declined to share the information due to being bound by an NDA, sadly. Looking through my pictures now, it seems I last had a crack at this in 2022. See, I so kindly wrote "open" and "close" next to the switches. If you figure it out, please do tell me. Those little switches, with the red buttons may need to be replaced.
×
×
  • Create New...