Fuel Starvation? Fuel Filters? Atmo.....

Just got back after taking the Alpine on a 2000mile holiday round Europe. Car was great, hardly a murmur and best fuel consumption was measured at 32mpg, although it probably averaged about 29odd. Not bad for a 22 year old car!
Only problem was after 1000 miles without a glitch, it cut out a few times under extreme load, usually whilst accelerating up hill at high speed. The car would start juddering and was obviously not getting enough fuel to it, because after say 10-20 seconds it would then get some more fuel and be ok for a bit. I figured the fuel filters, are there 2? were probably getting blocked.
Where is the first fuel filter located? is it in the front of the car near the fuel tank? I can't seem to see it. I have a replacement and it is quite large it seems but sure this is the correct filter as I got it looked up on my local Motor spares shop computer. Is the second filter in the engine bay to the right? This seems a smaller one and has two outputs, one to each carb I presume. Also could it be possible that the fuel pump is malfuntioning under load? I am more likely to think it is the filters.

It became a little worse the problem gradually and figured it was because the filters were getting more and more blocked. I seemed to get round it by feeding a little air backwards down the fuel line and it seemed to clear the blockage for a 100 miles or so and then it would start again.

I think I would go for the Filters as causing the problem and will change them as I think they havent been changed in the 7 years or so we have owned.
Any other comments/ experience of this type problem appreciated ....

on an atmo car the front fuel filter is located on the passenger side close to the fuel pump.

what age is the atmo, early cars had only one filter fitted and later ones had one on the rear bulkhead, but i have not seen one with 3 pipes before!

check that the inside of all the supply fuel pipes are not collapsing with old age or that they have been changed with proper feul pipe/hose inc the two on the bottom of the fuel tank.

also you will need to strip the carbs and clean them out if you are having problems with dirt.

check fuel pump pressure when pipes/hoses/filters have been changed, and check all your earths!

Well, the car is an early 1985 import, a LHD, probably one of the first into U.K, before the RHD's arrived here.
In the engine bay, on the right; am I correct in saying there is a unit which I have always believed to be the pump(?) but maybe I am wrong, because you mention that the pump is in the front area, near the tank? Right near this unit in the rear, which I think is the pump is a filter looking thing with one input and two outputs. Funny thing is it is stamped FIAT, a FIAT filter on an Alpine, weird? Could it be that this has been fitted after?
How do I get to the front filter if fitted? Where exactly is it located and can I see it without dismantling anything, etc? I have crouched under the front of the car and haven't seen anything that resembles a filter. I did strip the carbs, well the doubles and they were as clean as a whistle, so I am believing the prob lies with the filter(s)? I guess also the pump could be struggling under extreme load but I doubt that and am thinking filter(s)? Do you think this very early LHD has a different filter config to the RHD's. Help appreciated.

Thanks again Simon.

sorry Simon, you didn't say the filter was mounted in the Front, for some reason I have presumed that as I think I read somewhere it was but am not sure..... help!

well after a little bit of searching, am I right in saying that the front fuel filter is located by dropping the floor pan thing dead centre of the car? I have the new filter and will try fitting it if the former is correct? Thanks again.

the thing on the right hand side rear is the fuel meter for the trip computer.

the filter is at the front, behind the lower bumper cover.

also check your cut off solnoid on the single choke carb, these can also cause blockages due to the rubber inside the valve falling apart and being drawn into the idle side of the carb.

thanks, yes I found the front filter.
Turns out it is really small thing, much smaller than the massive one I got of my Motor Factors shop. Looks like the size you would fit to a 1 litre car or something! Was abit black looking also. Even though it is so small it must have been adequate though because it hasn't suffered this problem in 7years, not that I have used the car that much. It only recently appeared this problem and as I said under high load at 130kmph odd, often uphill accelerating hard. I have now fitted a larger one. Also thanks for the advice in inspecting the hoses, it did have a very minimal leak on one that attached to the pump near the filter.
Also the thing I thought was the pump(in the rear, on the right) that is actually the meter for the fuel computer, it had a filter looking type thing very near to it, kind of strapped to the side. It has one input and two outputs, well I don't know if they are inputs/ outputs but basically it has 3 hoses connected to it. I took this off thinking it was a another filter and blew abit of air down it. Could it be that this was causing a blockage because the air that came out after blowing down seemed not consistent. It is actually stamped FIAT this filter thing. What is that exactly? it is right next to the VDO Fuel meter thing, strapped onto it. It is metal and does kinda resemble a filter or trap or something?

how about a picture of these "things" you describe?

[img]http://s225.photobucket.com/albums/dd98/R_Alpine/?action=view&current=IMAG0062.jpg
Thanks Simon, yes the filter 'thing' is next to my hand.
Is this standard or is it something that has been added? What is it again? A filter, trap of some kind?
Find it odd that it is stamped Fiat.

Thanks again[/img]

Does anyone know what the circular compoment is exactly near to my hand, it has three hoses coming off it, one on the top and two out the side. Is it some kind of filter or trap? help.... !!!

Well, I'm sure people do know what it is(?) it is I think a standard part as it is displayed in the Club .PDF but anyway I got the car running again and it seems back to normal..... weird problem...

That the fuel pressure regulator.

yes well, I thought someone would answer eventually and not surprised it is you! Thanks for your knowledge again!

Just a bit of info 4 u. The unit u refer to is a flow meter device. It contains a small impeller which measures the speed of the fuel passing it on the way to the carb.Under the red potting compound there is a small circuit board which has a Hall Effect device on it, which picks up pulses from the impeller, which in turn via the circuit produces a patten of pulses which changes with increases in the flow.(this patten can be seen on an ossicillascope) The 3 pin connector on the side of the unit has 12v, Earth, and the pulses.The pulses are sent to the computer, and together with the pulses from the flywheel sensor calculate the mpg etc.The 3 pipes on the unit are 1 from the pump, 1 to the carb, and one returns unwanted fuel to the tank.Failure of this unit gives a mpg reading of 99.9.The other unit by your finger is an Antiperculation device. Fuel flows into the unit with perhaps some air bubbles in it and flows on through back to the tank.However fuel required for the carb is picked up from the bottom of the bowl via the cranked pipe coming out of the top, less any air bubbles.Clever is'nt it.I have had problems with the flow meter which will show up as a reading 99.9mpg, and this was caused by a dry joint on the circuit board.The potting compound can be removed CAREFULLY which reveals the underside of the board, I can give more info if required.However the first check is the 3 pin connector.With regard to your original prob,the chances of there being a restriction in fuel flow in this unit is very remote as bore sizes of passages within the unit are quite large.Hope this info is of interest to you.