Technical Brava Stalling

[neoseal]

Yesterday, petrol was low (fuel indicator light on) and suddenly my brava 1.2 started stalling. It idles perfectly but as soon as I press accelarator it revs up and down. It doesnt show fuel injector warning light on dashboard so I dont think there is problem with fuel injector. Last month this happened but then it showed fuel injector warning light and was solved by adding fuel injector cleaner. This time there is no light and even after adding fuel injector no improvement. I have checked all the spark plugs and leads as per previous posts, checked lamda sensor too but couldnt find the fault. Can it be the dirt in the fuel pump, which makes fuel supply irregular? I think this car is going to make an auto mechanic out of me.

 

[neoseal]

Sorry forgot to tell, it gave just 82 miles for 17 litres of petrol and before that as well just 220 miles for full tank. Ummmm something serious is wrong?

 

[jug]

you may have sucked some dirt from the bottom of the tank, it would most likely collect at the fuel filter. worth replacing it, they're cheap.

 

[neoseal]

It's 1.2 and fuel filter is in the tank with the fuel pump. I just noticed that fuel is coming out of fuel cap and when I opened the cap fuel poured out of it and refuse to return in the tank, even though the petrol is actually 3/4 tank. Any idea? I think the tank air vent is blocked too, bcos every time I open the fuel cap, it is sucked inside and I have to pull is open.

 

[jug]

sounds like the vent is blocked. that would make the fuel delivery bad at times. when a low pressure is in the fuel tank it would be hard for the pump to send fuel at the required pressure causing less fuel to be injected.

the petrol splashed out at a point when the fuel tank was at high pressure, probably due to temperature changes.

find that blockage

 

[neoseal]

Thanks Jug.

 

[neoseal]

I have now checked the fuel tank vent and I can feel the air through it so I think it is alright.
Today I noticed that fumes or vapour is coming out of my engine, it is definately not the exhaust smoke bcos there is no smell of it and that is why I presume it is water vapour. I couldnt see exactly from where but it emerged from around the lamda sensor, coolent hose and engine area near it. Now I am really worried, engine still hesitates on acceleration, this water vapour :bang:

The heater works fine, there is not water in the oil, checked all the HT leads for resistance (The resistance increases in proportion to the length of the leads, is it OK), all spark plugs are good.

AM I HEADING TOWARDS GASKET FAILURE?

 

[neoseal]

I took my car to a local garage here he says that the problem is with the throttle body and I have to change the whole throttle body? I doubt it? HELP

 

[jug]

im more confused now than i was at the start of this thread. i wish i could inspect the car myself. did he say why the throttle body needs replacing? its very rare that you actually need to replace the throttle body, parts of it maybe but not the whole thing. there is nothing i can think of that the throttle body could do to create water vapour, or fumes. i doubt a throttle body fault would cause the stalling and poor performance and fuel economy either. try disconnecting the throttle position sensor to see if the stalling stops, and check the accelerator cable is opeing the throttle body correctly and it doesnt stick, a smooth movement is needed. apart from that the throttle body is just an air intake pipe with a butterfly valve in it, what could possibly need replacing? unless you've taken a hammer to it??

 

[neoseal]

That's what I argued about with the mechanic, but now I have got a throttle body from scrapy and he is changing it, let's see...
You may recall, my throttle potentiometer problem is still there, so I was driving with it disconnected.
The vapour and fumes have stopped.
Let's see, finger's crossed

 

[jug]

oh yeah i forgot about the TPS problem, if you got a complete throttle body complete with TPS you shuld have that problem solved, and hopefully a working TPS will solve other problems. i hope

 

[neoseal]

I got my car back yesterday evening, throttle body replaced (still doubtful bcos the throttle body he gave me back still had scrapyard markings) Anyway, not TPS is connected, car runs fine but misses once in a while. Mechanic says that he had to reprogramme the TPS. ????? Everything seems fine for the time being.

 

[jug]

i've heard people mention the need to program the tps on this forum before, but i've never come across it in my own experience. judging from what i have read on this forum i would believe he did do it; but dont ask me how its done??

i wonder if the ecu has been reset after all this work has been carreid out. it may be worth a try, leave the battery disconected for an hour so the ecu can relearn the operating parameters, that may improve the occasional misfire. also watch your petrol consumption, hopefully you should get much more than the 220miles per tank you have been getting.