Technical Seicento fuel filter

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Technical Seicento fuel filter

nrw1950

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Hi All .

Can anyone help please? I am trying to change the fuel filter on a 2002 (187) 1.1 Seicento . I don't think it has ever been changed from new and the car is running really rough .

I have read conflicting information - some saying it is in the fuel tank - some saying it is under the car - some saying it is under the n/s wing.

I have followed my fuel lines and they lead under the n/s wing and return to the carb - I have removed the plastic shroud and have removed a canister but it does not look like anything I have seen on the web. I cannot see any way of getting into it and wondered if anyone can help please.

Here is a photo

https://www.dropbox.com/s/833ts6ooe7posv8/Fuel filter.JPG?dl=0
 
Further thought, yours is MPi so will be readable. Go that route first.

D

You have lost me there..
Do you mean it is elsewhere?

( edit.. possible to read the rail pressure..?)


There is a useful guide on the in.tank.pump

Set.up in the mk1 punto section.


I have often wondered if the filter can be 'back.flushed'...
https://www.fiatforum.com/punto-mk1-guides/315620-fuel-pump-assembly-replacement-punto-1-1-spi.html?p=4257783

But no doubt a good used one is so cheap it is not worth the bother.
 
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You have lost me there..
Do you mean it is elsewhere?

( edit.. possible to read the rail pressure..?)


There is a useful guide on the in.tank.pump

Set.up in the mk1 punto section.


I have often wondered if the filter can be 'back.flushed'...
https://www.fiatforum.com/punto-mk1...mbly-replacement-punto-1-1-spi.html?p=4257783

But no doubt a good used one is so cheap it is not worth the bother.

The OP has suggested that the fuel pump might be the issue, but doesn't indicate whether he has live scanned the car for the problem.

Being MPi this is easier than SPi.

It might not be the fuel filter, I thought it better to read it first and chose the part based on knowledge, not guesswork.

D
 
Hi

Thanks all for your replies

I have now found it to be a Vapour Trap

I took the car to the garage to do a diagnostics scan but they said it showed no codes - I personally do not believe them as they could not find the diag plg and had to tell them and also they did not have the printout when I asked them as they said they threw it away as there were no codes - As the car has never been scanned in 10 years I find that unlikely -

I spayed carb cleaner into the carb when opening the throttle and it ran perfectly but when opening the throttle normally it splutters

It is my wife's car and she does not use it much - when she had this problem before if she put more fuel in it - it cured the problem - Strange
 
These wee cars benefit hugely from 'Italian Tuning'.

Check the fluid levels, get it warm then give it the full moo for half an hour minimum.

Works wonders

D

Have had it running on my drive and tried giving it full moo but it still struggles to get up there:)
 
Step back a bit. The filter (which is in the tank on an MPI) is very unlikely to be blocked so much that it affects the fuel flow. Modern benzina doesn't have all the bits that came free with every gallon of 2-star back in the day (kids, ask your dads).

Also, Seicento normally/as standard has Multipoint Fuel Injection, not a carburrettor, so if you have a carb' fitted then that's probably the problem right there. :D

If it fails to pick up revs using the throttle but goes well with a squirt of the magic fairy juice, then it's either electric or fuel that's the problem.

Check that all four cylinders produce a spark. Connect the HT lead of one cylinder at a time to an old plug laid on the engine (don't hold it there unless you're very well insulated) and run the engine or turn it over to see whether or not there is a spark.

If there's a duff coil, you'll find that two of the plugs don't fire and the other two do (I think they're paired 1&4, 2&3). New coil is a simple swap and not too dear.

If the sparks looks okay, then the problem could be a duff injector (if you have MP's in your I). Remove the connector block from each injector in turn and stuff a multimeter against the terminals .. then crank the engine over and see if you get any volts. You can use those glass bottomed bulbs with the wire tangs for this... just unbend the wire tangs and hey presto, they exactly fit into the injector plugs.

If you have sparks and injector juice, you need to take out the injectors and see whether they all work properly. I would do the "spark plug" test.. remove each plug and see whether one of the plugs looks cleaner or dirtier than the others. If an injector is lazy, I would expect the plugs to be cleaner (leaner) in that cylinder.

If you can get hold of a spare good injector for not much money, then swapping out the most suspect one would be the DIY method of solving it.. a garage might have a flow tester to test the injectors and make it less of a hit and miss and pray job... (but would require money).

If it runs well enough to run it around.. put some injector cleaned in the tank. RedX or something like that... use the maximum suggested dose and run the engine around for half an hour to get it properly hot.. and use some revs to vary the fuel flow. You don't need to cane the beast to an inch of it's life... just give it a workout.

If the sparks, injection and injectors all sound good then you may have duff fuel pressure... the regulator might be weedy but there's no easy way to test this (you need a fuel pressure gauge, which matey mechanic will have but for a fee).

You can test there's fuel in the fuel rail by disconnecting the fuel line to the injector rail and cranking the (cold) engine over. Catch the fuel in a small jar and don't smoke any ciggies while you're doing it. If you get a gush of fuel then the regulator and the pump (including filter) are fine. If it's a weedy dribble... then one or the other or both could have failed.

Don't rule out the pump, if there's no good fuel flow.. sometimes it "works" but may be spinning but not actually delivering, if the pump vanes are detached... or the lifting pipe/if it's rubber could be split.. etc.

You won't get any error codes if the pump/regulator have a problem since they're mechanical. Injectors, coils and plugs might, since they will be giving a duff resistance to the ECU... but the Cinq'/Sei is old and the systems were not so flashy back then (early Cinq's came with a ride-on mechanic) so the car OBD might not be as clever as systems are now.


Ralf S.
 
Step back a bit. The filter (which is in the tank on an MPI) is very unlikely to be blocked so much that it affects the fuel flow. Modern benzina doesn't have all the bits that came free with every gallon of 2-star back in the day (kids, ask your dads).

Also, Seicento normally/as standard has Multipoint Fuel Injection, not a carburrettor, so if you have a carb' fitted then that's probably the problem right there. :D

If it fails to pick up revs using the throttle but goes well with a squirt of the magic fairy juice, then it's either electric or fuel that's the problem.

Check that all four cylinders produce a spark. Connect the HT lead of one cylinder at a time to an old plug laid on the engine (don't hold it there unless you're very well insulated) and run the engine or turn it over to see whether or not there is a spark.

If there's a duff coil, you'll find that two of the plugs don't fire and the other two do (I think they're paired 1&4, 2&3). New coil is a simple swap and not too dear.

If the sparks looks okay, then the problem could be a duff injector (if you have MP's in your I). Remove the connector block from each injector in turn and stuff a multimeter against the terminals .. then crank the engine over and see if you get any volts. You can use those glass bottomed bulbs with the wire tangs for this... just unbend the wire tangs and hey presto, they exactly fit into the injector plugs.

If you have sparks and injector juice, you need to take out the injectors and see whether they all work properly. I would do the "spark plug" test.. remove each plug and see whether one of the plugs looks cleaner or dirtier than the others. If an injector is lazy, I would expect the plugs to be cleaner (leaner) in that cylinder.

If you can get hold of a spare good injector for not much money, then swapping out the most suspect one would be the DIY method of solving it.. a garage might have a flow tester to test the injectors and make it less of a hit and miss and pray job... (but would require money).

If it runs well enough to run it around.. put some injector cleaned in the tank. RedX or something like that... use the maximum suggested dose and run the engine around for half an hour to get it properly hot.. and use some revs to vary the fuel flow. You don't need to cane the beast to an inch of it's life... just give it a workout.

If the sparks, injection and injectors all sound good then you may have duff fuel pressure... the regulator might be weedy but there's no easy way to test this (you need a fuel pressure gauge, which matey mechanic will have but for a fee).

You can test there's fuel in the fuel rail by disconnecting the fuel line to the injector rail and cranking the (cold) engine over. Catch the fuel in a small jar and don't smoke any ciggies while you're doing it. If you get a gush of fuel then the regulator and the pump (including filter) are fine. If it's a weedy dribble... then one or the other or both could have failed.

Don't rule out the pump, if there's no good fuel flow.. sometimes it "works" but may be spinning but not actually delivering, if the pump vanes are detached... or the lifting pipe/if it's rubber could be split.. etc.

You won't get any error codes if the pump/regulator have a problem since they're mechanical. Injectors, coils and plugs might, since they will be giving a duff resistance to the ECU... but the Cinq'/Sei is old and the systems were not so flashy back then (early Cinq's came with a ride-on mechanic) so the car OBD might not be as clever as systems are now.


Ralf S.

Thank you so much for taking the time to write a detailed post:

1 . I have tried all the plugs and I am getting a good spark on all of them - I have changed them all to be on the safe side

2 . I have changed the plug leads

3 . I have filled it up with fresh fuel and Wynns Injector cleaner and taken it for a long drive getting some high revs

I will check the injectors tomorrow and fuel flow tomorrow and let you know .

Thanks again
 
I presume the old plugs looked normal if you say you swapped them over but didn't add "one of them was a bit manky"... :) At least that eliminates the ignition or any wierdness in the ECU or temperature sensors etc. that could cause a fueling/ignition problem - you'd likely get uneven burn and dirty plugs in that case.

It's also positive that you don't have other symptoms (for instance a leaky head gasket would affect how the car runs... but you would see vapour out the back/falling coolant level and a nice clean spark plug on the affected cylinder.

My money is on one of the injectors at the moment. It's worth checking that you get a signal at the connector first, just to eliminate any problem from that end, but a mecahnically failing injector is more likely than one injector not being sent the signal to fire but the other three are.

It's curious that the spark plugs don't give away which cylinder (injector) could be the culprit. Are they all uniformly identical or is one slightly lighter than the others?

An injectors clean-out, if one is just blocked is circa £80 but if it's a duff injector that no amount of cleaning will fix, then a new (even Magneti Marelli) one is around £20 on Fleabay... (obviously I don't know if these would fit your particular car), so new ones would seem to be the better option, if one or more of yours are dirty/blocked or faulty.


Ralf S.
 
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