petrol tank creating vacuum

[tvrscouser]

after a confrontation with a ford transit had to send the tvr to the garage got the car back started her up funny banging noise occured from the rear of the car I have put it down to the fact that the petrol tank is imploding, when I fill up with petrol remove the filler cap tank draws in air has anybody out there got a solution if so let me know

[Ballistic Banana]

After turning cap up tight, unturn half a turn.

BB

[satman]

You could try drilling a very small hole in the filler cap???

[z_chromozone]

Funny banging noise. It doesn't sound like tank to me. I don't know what model you drive, but the tank on the V8S will certainly not implode.

Does it still make the noise when the fuel cap is open. If it does check the exhaust mounts, fuel pump mount etc.

Z

[JonRB]

Surely all petrol tanks have a breather pipe to let air in as the fuel is drawn out, otherwise it would leave a vacuum.

I would therefore assume that your breather pipe is blocked.

[rev-erend]

Your profile does not say what car you have !

For Griff's, Chims, Cerbs : Read the hand book - it does actually say to leave the fuel cap slightly loose.

[catretriever]

Exactly the same on my Griff and loosening the cap generally sorts it

!Donk!

oops...there it goes again...

[zumbruk]

satman said:

You could try drilling a very small hole in the filler cap???

That's an MOT fail.

I expect the carbon canister is clogged up. See the Bible for details.

[satman]

zumbruk said:

satman said: You could try drilling a very small hole in the filler cap??? That's an MOT fail. I expect the carbon canister is clogged up. See the Bible for details.

Dont whatever you do, dont drill a hole in the cap!...its an MOT fail!!

>> Edited by satman on Thursday 14th October 11:41

[sacha]

common daily occurence with a t350! especially when you do a long drive the noises continue for a good hour when you arrive!

[GreenV8S]

The breather hose is via a carbon cannistor (in the boot on a V8S, down in the front wing on a Griffith). There is a separate vent from the carbon cannistor to the engine that purges fumes from the carbon cannister when the engine is running. It is quite possible that the vent to or from the cannister is blocked which would produce suction in the tank as fuel is used up, its also possible that if the inlet to the cannister was blocked the tank could see manifold depression (LOTS of suction).

[spend]

There is a solenoid valve which is opened briefly by the ecu at 3000rpmish to vent the charcoal canister IIRC. If you've had any work done near the canister there may be pipes or the electrical connector disconnected, but if the pipes were disconnected it would probably be venting the tank or manifold all the time. Its also possible that your carbon canister is plain clogged up. If you get to it blow down the pipes to check. My Chim used to bang until I reconnected the solenoid!

Dave

[tvrscouser]

hello tivvers thanks for the info, which i will be
putting to the test at the weekend although I definately wont be drilling small holes in the petrol cap, the favourite would appear to be a carbon filter which clog up i will keep you informed as to what the problem is, for those of you who wanted to know the model it is a chimera nad it is the first poblem I've
had with the car