Jump to content
SAU Community

Recommended Posts

When I turn my car off in 37c+ weather the fuel pump makes this weird as hell vibrating whine, totally different noise to when it is priming or running though. I've even got a mate to be sitting with a multi meter ready and the pump is getting 0v but it still makes this weird as hell whining/buzzing/ringing noise for maybe 15 seconds after the car is switched off.

Only happens if the car has been sitting in the sun and I've been driving around town getting everything stinking bloody hot, could it be fuel boiling or something odd? Anyone experienced things like this before? The pump was replaced before I got the car but I believe it is a nismo drop in for an R32, it is however still using the stock wiring loom and getting ~11v.

Ideas?

It's not working then.

The carbon canister is only a part of the evacuation circuit that sucks all the fumes from the tank and into the manifold. There should always be vacuum in the tank, (which is sometimes mistaken for pressure) or the system isn't working as designed.

My old Zoob RX Turbo used to pressurise its fuel tank in hot weather and if it was real hot (hight 30s/40 like today) I didn't tighten the cap . Its hardly going to fall out and I'd nip it up if I stopped anywhere .

I think you can get weird things happening because the pump is trying to return fuel to the tank which is at higher than normal pressure .

I think some of these problems occur because the fuel pump is circulating a lot more fuel than is necessary for the power being used and its possible that at low speeds the steel fuel lines may be absorbing some radiant heat from baking hot roads .

I think manufacturers have sometimes integrated a heat exchanger into the air con system because of fuel temp problems in hot hot weather , may have been an early V12 Jag can't remember .

A .

When I turn my car off in 37c+ weather the fuel pump makes this weird as hell vibrating whine, totally different noise to when it is priming or running though. I've even got a mate to be sitting with a multi meter ready and the pump is getting 0v but it still makes this weird as hell whining/buzzing/ringing noise for maybe 15 seconds after the car is switched off.

Only happens if the car has been sitting in the sun and I've been driving around town getting everything stinking bloody hot, could it be fuel boiling or something odd? Anyone experienced things like this before? The pump was replaced before I got the car but I believe it is a nismo drop in for an R32, it is however still using the stock wiring loom and getting ~11v.

Ideas?

I know the exact noise you mean, my motorbike has always made the same noise when its hot, from new. Sometimes even 24 hours + after driving it.

It's not working then.

The carbon canister is only a part of the evacuation circuit that sucks all the fumes from the tank and into the manifold. There should always be vacuum in the tank, (which is sometimes mistaken for pressure) or the system isn't working as designed.

Now that you mention it, that might be the case. Will investigate.

On a similar topic why does my car stall after first start particularly when cold?

Idle air valve sticky. Takes a moment to open up far enough to stabilise idle. Moment is too long. Clean up the valve so it moves faster and maybe it will react fast enough to catch the idle.

Ok, Thanks ;)

Some strange replies here so I'll add mine.

While the car is running, fuel is circulating in the rail at pressure controlled by the fuel reg.

Turn the engine off and the rail stays at pressure, maintained by the fuel reg at one end and the fuel pump at the other.

All good.

Now heat soak the fuel rail and that petrol will quickly expand, it has nowhere to go but to open the fuel reg and discharge to the tank.

The noise you're hearing is the pressurised fuel slowly bleeding through the reg back to the tank until rail pressure has stabilised.

Nobody else experienced vapour lock back in the old carby days?

But no Carbon cannister is worth +1000 street creds. :D

but seriously my carbon canister has carbon falling out of it when i turn it upside down...is that normal?

I'm quit happy to reinstall it if I know it works..I love having more junk in the engine bay to make life hard when I am working there..

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

    • Well, if it wasn't a GTR I'd say that killing an RB is a perfect opportunity to put in a proper engine. In your case, proximity to Brabus and AMG V12s would be a no brainer for any RWD Skyline engine death event. In my case, because my car is my daily, anything that I do wrong that means I have to do it again is both an absolute pain in the arse (simply having to do it again), and also a doubling of the pain associated with having the car off the road to work on it. I would class a botched head gasket install as not being "engine death causing". More a case of "f**k it's still leaking!"
    • Yeah, this is more stuff like transmission/clutch R&R. Intake manifold R&R. It's not super complicated, but each step matters and you need to be careful and patient. I have heard stories for example of people not figuring out the super coppermix twin plate orientation and getting it wrong on assembly. Removing a cylinder head and putting it back in once it's machined isn't that hard, following torque sequence to install some cams isn't that hard either, but somehow I've seen a lot go wrong between here and there. Scraping off all gasket material isn't that hard either, but I've seen shops ruin heads by using a roloc disk that was too aggressive.
    • There is some shops in Germany that have quite a bit of experience with JDM performance 4-wheelers. I think if it actually comes down to it I'd let one of them do the head gasket. Killing an RB26 is too expensive a risk just to save some money by doing it yourself.
    • There are certain tasks, like replacing head gaskets, where it is very much best to already know what you are doing, and if you are not already an expert, then the next best thing is to have an expert around to help it get done. Little annoying checks and steps that are easy to forget or not interpret the results of properly, etc etc. It is hard to convey that to someone as a lesson prior to taking on a job, because there can be a whole list of "if you see this then it means that", or "if this is what you find then you will need to do these other 4 steps first". All the little bits of knowledge around sealant choice (ie, sealant at all? or no sealant? sealant only in certain parts of the gasket? sealant for this type of gasket but not that type of gasket? etc etc) cleanliness checks and methods, surface straightness and finish checks and methods, etc etc, all combine to mean that people who have done many of the same type of job will struggle less to get a good result than someone who hasn't done it before. I've been around this stuff since forever. But I will still consult with my expert(s) before taking on the big stuff with higher risk profile.
    • Well if I end up having to do the head gasket I will certainly find the necessary tools and instructions before beginning... Let's hope it won't come around.   Definitely. Depends on the job but I think "if you want it done right, do it yourself" applies almost every time
×
×
  • Create New...