Last wish of an opel corsa on death bead, you help might rejuvenate her

Subject : opel corsa 1.4, 2000, 90000Km

Observation :

For the last 6 months, the subject has been displaying varied behaviour at the time of starting. If the fuel tank is filled half or one third it starts and runs as smooth as hot knife on butter. 

However as the fuel level drops below one third, it takes 6-7 screeching attempts to start. During these 6-7 attempts you can possibly hear the fuel pumps whizzing sound. Also it moves-halts-moves-halts for some time and then runs properly. Subsequent starting within the next 3-4 hours is smooth. 

This problem is accompanied with a severe drop in mileage to embarrasingly low levels!

Is this a Fuel pump problem?

Is there possible fuel leakage or inefficient burning due to fuel pump problem, what can be the reason for sudden drop in mileages (i'm afraid the mover and packer who shifted the subject recently had attempted to molest her) 

Please advise.

Leakage: look for strong petrol smell while passing the parked car.

There is no "unsufficient burning" unless your car misfires or has a very low pickup (indication that a cylinder is not firing)

The 'embarrassing low level' of FE is not mentioned, nor is the 'normal' one, so we too are clueless.

To hazard a guess - it still looks like fuel pump, or choked/pinched fuel supply lines, as 'the subject' behaves ok if the tank is half full.

BTW, Welcome to CW forums! With your writing 'skills', you would enjoy it here, so would we!

Atul - you say the "i'm afraid the mover and packer who shifted the subject recently had attempted to molest her" - was the car driven or moved in a truck or something? Was it out of your sight for a prolonged period - when someone might have tried to tamper with it? Is there any sign of the car being involved in an accident (however minor) or something? What is the quality of fuel in the car as it stands now?

check the fuel filter or fuel pressure valve

Atul

Go for a thorough cleaning of the Fuel Tank. 

Thanks ALL 

Hi Krishna - subject dropped from a poor 8-10 to an abyss like 5 kmpl, i am not sure of this as due to the starting problem i cant drain down her guts empty and need to refuel in advance. Can a fuel pump problem lead to insufficient/excess fuel delivery leading to low mileage ? what can be the reasons for sudden drop in mileage (not that we had anything great to start with )

Why is the fuel pump working fine when the level is good, is it a setup suspended in the middle of the tank, i dont think this should be the case!

Hi Rohit- car was partially shifted in truck and road driven for some 100 Km, i doubted molestation as the chap had removed the wire that operates the speedometer (to avoid increasing the kms on the dial), which i had to get connected. No there was no accident.

Can quality of fuel cause damage to fuelpump, possible erroneous mixup of diesel in petrol make ? i am myself not very confident of fuel quality in this part of the hinterland

Hi Sunny - you sure have good diagnostic skills as i have not changed the filter for quite some time, maybe the pressure valve had a heart attack (its 9 years old), ill get them checked

Hi Selva, thanks for your valued ' two cents', have you heard of such disases getting cured this way, ill anyway try that.

Danke schön!    that means Thanks (in Advance for your current and future replies) in German, dont forget the subject has German genes ! 

Atul - the 5kmpl is indeed embarrasingly low. You did not mention if the engine burns oil (i.e., if the oil level falls down often), or if the exhaust is smoky. Does it have adequate acceleration? For example do you have to rev hard to get it to move? Does the engine knock/shudder/stall often?

If everything else seems normal, (like no smoky exhaust, oil level normal and so on) check if there's any parasitic loading on the engine - like a tight alternator or AC compressor. These place some load on the engine, especially the compressor - that's the reason why mileage drops a bit when the AC is ON. Check if the brakes (parking brakes in particular) are jammed against the discs/drums causing extra effort for the engine (this is the same as driving with brakes partially applied and will surely affect mileage badly). Check if the clutch engages properly transferring the power to the gearbox efficiently.

Apart from these, I can't think of any more possibilities...perhaps you could give more symptoms/observations...

Hi did you send her to a doctor?

Hi rohit,

well engine oil level is ok, smoke is not an issue, as long as the fuel level hasnt fallen below half; acceleration is ok (even in case of low fuel level; acceleration is slow for the first 200 meters), also the breaks are not an issue, clutch issue i cant comment upon.

i have observed the fuel indicator to swing a little bit, is it a possibility that the indicator is not sensitive enough to indicate the correct level, leading to a wrong assessment of fuel level in the subject, also is it possible that some issue (pore, small craks) in the tank lets the vehicle fuel evaporate gradually.

do share your 2 cents!

Well, get the fuel pump and lines checked. Next is the fuel gauge - especially the sensor (or Float/POT) inside the fuel tank.

For leakages you have to smell around the car and especially the fuel tank - if possible by parking in an enclosed place (but don't stay there too long!!). Check if you can smell fuel when you start the engine (I guess some smell is normal if the car is old - but it should disappear within a few seconds).