Hot day + long drive = no power...

RG · 18-02-2007, 06:27 PM

After a long drive on Friday from Ballarat to Phillip Island my car decided that it was a powerless pig. I filled up at Mobil on the ring road with their 8000 fuel and all was fine until I gave it a bootfull just before I got to the Island. All it would do was hold gears and make a lot of noise but just had no balls, to the point where it struggled to make it to the top of the rev range. As soon as the weather cooled down it came good but the next day it happened again, this time after only half an hour or so. I drove to Dromana and filled up again with BP ultimate and all was good again, when I opened the fuel cap it seemed to have a LOT of pressure built up. Went well until today when I filled up on Ultimate again on Stud road, not as bad but still very noticeable. WTF is going on, it's obvioulsy a fuel issue but why so intermittent? Are the servos using a blend that is not intended for such hot weather or is it just my car really not liking the ambient temparature? And before anyone says that cars don't make as much power on hot days, I know that but this is way too much power loss to be normal. Any help would be appreciated.

AU2PWR · 18-02-2007, 06:42 PM

Russell , Its just the Unichip in the car , Give it to me and it will be fixed ..

and if you need a Hand , Get whoosha to do it !

b2tf · 18-02-2007, 06:47 PM

Quote:

Originally Posted by AU2PWR

Russell , Its just the Unichip in the car , Give it to me and it will be fixed ..

and if you need a Hand , Get whoosha to do it !

Do you ever post anything useful or related to the issue?

My car suffers from this a bit too, when I take the fuel cap off a big burst of pressure comes out.

Tech Trainer · 18-02-2007, 07:01 PM

If you just take the cap off and put it back on does the issue resolve itself or is it still there?

b2tf · 18-02-2007, 07:02 PM

Quote:

Originally Posted by Tech Trainer

If you just take the cap off and put it back on does the issue resolve itself or is it still there?

mine will only do it once then its fine, just a pressure release. not something that really worries me but it definitely does affect its performance i find.

NeishaXR8_347 · 18-02-2007, 07:04 PM

Mine has the pressure build up which is normal to some extent. With the car being so gutless im going to say its something in the tune, how hot was it when it was tuned? But could have just been a bad batch of fuel, i only fill mine with BP ultimate and use a servo next to my house which has a lot of turn around so the fuel is always fresh.

I'd be talking to G&D and see what they think. It may be nothing but defenantly doesnt like the hot air. Was she pinging?

Shaun

RG · 18-02-2007, 07:14 PM

Quote:

Originally Posted by Tech Trainer

If you just take the cap off and put it back on does the issue resolve itself or is it still there?

Makes it better but the issue is still there

Quote:

Originally Posted by NeishaXR8_347

Mine has the pressure build up which is normal to some extent. With the car being so gutless im going to say its something in the tune, how hot was it when it was tuned? But could have just been a bad batch of fuel, i only fill mine with BP ultimate and use a servo next to my house which has a lot of turn around so the fuel is always fresh.

I'd be talking to G&D and see what they think. It may be nothing

Shaun

The thing is is was 32 degrees when it was tuned. I thought it was just a bad batch of fuel but could I be unlucky enough to get two bad tanks in three days from to seperate companies? I'll call G&D and have a chat to Matt in the morning, after I get my new tyres

: .

Quote:

Originally Posted by AU2NOPWR

Russell , Its just the Unichip in the car , Give it to me and it will be fixed ..

and if you need a Hand , Get whoosha to do it !

You're probably right Dan, and you will get my Unichip once I get my Edit and you're money. lol

:

AUTickford · 18-02-2007, 07:17 PM

Whats the go with stressing out about a bit of pressure isnt it normal to hear a little psssh when the caps taken off, how would that effect the performance?

RG · 18-02-2007, 07:24 PM

Quote:

Originally Posted by AUTickford

Whats the go with stressing out about a bit of pressure isnt it normal to hear a little psssh when the caps taken off, how would that effect the performance?

A little pressure release is normal but this isn't just a little bit, it's a lot as I said. I'm also not stressing, I just don't like it when my Stroked AU XR8 can be beaten by a bloody stocko 6.

AU2PWR · 18-02-2007, 07:41 PM

Quote:

Originally Posted by b2tf

Do you ever post anything useful or related to the issue?

Sorry , Didnt Know joking with mates was Banned on your forums ..

:evil3: Russ , did you change your Fuel Collectors Over ? That one you Picked up last night might have really Bad Stale fuel in it , or Dirt n stuff ..

RG · 18-02-2007, 08:16 PM

Quote:

Originally Posted by AU2PWR

Sorry , Didnt Know joking with mates was Banned on your forums ..

:evil3: Russ , did you change your Fuel Collectors Over ? That one you Picked up last night might have really Bad Stale fuel in it , or Dirt n stuff ..

That one that I picked up last night was the stocko fuel pump. I forgot to pick it up last time I was at G&D so I got Whoosha to do it for me.

NeishaXR8_347 · 18-02-2007, 08:19 PM

Was the car pinging at all when it was running poorly? Being tuned on a 32deg day is fairly good and should stay consistant. I just hope its not a re-curing problem that has existed from before when the 5L went and it is showing its head again.

RG · 18-02-2007, 08:21 PM

Quote:

Originally Posted by NeishaXR8_347

Was the car pinging at all when it was running poorly? Being tuned on a 32deg day is fairly good and should stay consistant. I just hope its not a re-curing problem that has existed from before when the 5L went and it is showing its head again.

No pinging at all. It revs cleanly but just a lot slower than usual

: . The only thing I can think of is the Unichip.

Yellow_Festiva · 18-02-2007, 08:33 PM

I had the same problem with the festiva, it was the air con idler switch apparently. well whatever adjusts the engine when the aircon is on. (it was faulty / dirty i cant remember)

On a 40 degree day the air con up full bore and the engine was just dead...

Perhaps this is you issue??? was the air con on during this time???

NeishaXR8_347 · 18-02-2007, 08:34 PM

Quote:

Originally Posted by RedXR347

No pinging at all. It revs cleanly but just a lot slower than usual

: . The only thing I can think of is the Unichip.

Lets hope its just the Uni then, Look at all the issues that Austin (B2TF) was having with his. Keep saving and the edit will come soon enough. But defenantly speak to G&D and see what they think of this problem.

RG · 18-02-2007, 08:37 PM

Quote:

Originally Posted by NeishaXR8_347

Lets hope its just the Uni then, Look at all the issues that Austin (B2TF) was having with his. Keep saving and the edit will come soon enough. But defenantly speak to G&D and see what they think of this problem.

I spoke to Matt on Friday and he thought ambient temp was the problem. It doesn't help that I need bigger injectors and that the Unichip just doesn't have the capabilities to tune the stroker either. Ahh well the Edit will fix all, if I ever get the money for it. Bloody melting tyres...

:

b2tf · 18-02-2007, 08:42 PM

Quote:

Originally Posted by NeishaXR8_347

Lets hope its just the Uni then, Look at all the issues that Austin (B2TF) was having with his.

out: Unichip

out:

Tech Trainer · 18-02-2007, 10:02 PM

Now the thing is here when you release the cap you hear rushing air. Is the air escaping from inside the tank or is it trying to fill a void created by a vacuum?

If it is the later I would suggest you have a look at your canister purge valve and make sure it is operating correctly.

The part that interests me is that if you pressurise a fuel tank it should not produce fuel starve, however if you create a vacuum in the tank it will work against the draw of the fuel pump.

Let me know how you go with this one please guys.

Tech Trainer · 18-02-2007, 10:09 PM

Just wondering when was the last time you changed your fuel filter?

What sort of fuel pump are you running?

RG · 18-02-2007, 10:33 PM

Quote:

Originally Posted by Tech Trainer

Just wondering when was the last time you changed your fuel filter?

What sort of fuel pump are you running?

Fuel filter I'm not sure about but the pump is a Walbro 255. With the pressure I'm not sure but I don't feel air on my hand coming out so it could be vaccuum.

AU2PWR · 18-02-2007, 11:02 PM

Get Matt to Look at it , Might Just be the fuel you used , but still be safer than Sorry Russ ,

Whooshas Sons car had a bit of a Bad Run , the AU like mine , got Bad Fuel @ BP Westernport , Coughin and Splattering Everywhere ,

Run Octane Booster/Injector Cleaner in it , Cleared it Up !

Maybe you should get Kevs Injectors sooner than Later ..

Tech Trainer · 19-02-2007, 07:20 AM

If you don't know when your fuel filter was replaced moree than likely it has not been replaced.

A good way to check this is to remove the filter try ing not to let too much of the fuel spill. The block the inlet and outlet and shake the filter for around ten seconds. Now blow back through the filter in the reverse direction.

Now if you blow back through the filter in the correct direction there should be minimal resistance. The more resistance there is the more blocked your filter is.

As for your Walbro it should be fine.

RG · 23-02-2007, 10:23 PM

Well I fixed it, it was the filter. Pulled it out (that was fun...NOT) and shook it around and tried to blow through it, which was hard. Shook it back out against the flow and a truckload of black grainy crap came out so no wonder I was having issues.

**GasoLane** · 24-02-2007, 04:33 PM

Quote:

Originally Posted by Tech Trainer

The part that interests me is that if you pressurise a fuel tank it should not produce fuel starve, however if you create a vacuum in the tank it will work against the draw of the fuel pump.

As mentioned above, You could expect a little pressure on a hot day but this should not affect fuel flow however if it's sucking air in it I would expect it making the fuel pumps job a lot harder. Either way I'd be checking the tanks breather system.