Car not running right advice
 

Right car is constantly misfiring/ hesitating (Sounding like a tractor) throughout the rev range. Sometimes dieing at junctions, sometimes stuck at between 2500 and 3500 revs no changing down or anything makes a difference you have to pump the accelerator just to keep momentum at all. have changed the fuel filter, cleaned the carb and jets to no avail, the car seems fine when first driving then as it gets warmer gets worse. Has not been right sice it died on the way home a few weeks ago. Think maybe the rolling road is my best tool to use but wonder if anyone has any ideas first?? Very frustrating 44 mile round trip to lincoln today. All the obvious things have been eliminated. I am sure it is something simple but what else can people suggest??
2.1 pinto with twin webers. I dont think enough fuel is going through when you watch the fuel filter, any advice would be greatly appreciated. Car has not had any issues for previous 7000 miles so no clues there.

Could it be an ignition problem? plugs/leads etc. I don't think fueling would make it sound like a tracktor, that sounds more like a misfire. Although all your other symptoms do suggest fueling.

Have you checked the float bowl levels and needles?

Four things are required for internal combustion to work: compression, air(oxygen), fuel and a spark to ignite it all. This means there are only a few possibilities that are causing your problem.

1. Compression, do a compression test, this will show up any problems with valves sealing and or piston rings/bore wear. Not the most likely culprit for the problem you describe.

2. Air, is the air filter clean? If the engine can't get enough, or alternatively gets too much(manifold gasket or carb gasket leaking perhaps?), it will be difficult to start and won't give good performance, possibly to the point of what you describe.

3. Fuel, is the engine getting enough? A poorly fuel pump or blocked fuel filter can lead to fuel starvation giving symptoms like you describe. Also blocked jets in carbs can cause similar problems.

4. Spark, is the coil performing properly? Are the HT leads in good condition? Is the timing set correctly?

These are the basic steps to sorting your problem. My guess would be ignition problems, either a coil failing or timing out by a significant margin but it could just as easily be a leaking manifold gasket.

D.

Some have had problems with muck in the tank blocking filters on more than one occasion.

Worth a try.

Check that air is able to get in to your tank. If you are pulling a vaccum as the fuel is pumped out it will cause fuel starvation, which could give a problem like you are describing. Fast way to check is to undo the fuel cap when the car is playing up. You will hear air being sucked in to the tank and the running will return to normal if this is your problem.
Best of luck with fixing it.
Enoch

Is there a vapour trap/regulator in line before the carbs.

Is it a mechanical or electric pump.

have you checked the tank outlet?


TT

Thanks all.
 

Thanks all,

enoch car idles fine, if it is misfiring and i pull over to the side of the road and undo the tank will this still work??

Davey, car starts and idles fine, problem is not constant, more driving carefully then once you give it the beans it appears and stays, will check fuel pump, fuel filter cleaned and checked, carb jets checked and cleaned. Coil and timing need checking.

david, Whats the best way of checking the float bowl levels?? Just take the top of the carb and look?

All car ran fine for 70 miles then would not start at all. left till recovery truck arrived. Next day starts fine but problem appears. The fuel filter takes about 10 seconds after stopping the car for the filter to fill back up to the right level, (Just small bubble at top)

may be fuel vaporisation..

do a googal..

and do a long mixed run with no bonnet (expels heat)


TT

I would defo check ignition timing. Have known sismilar thing on golf gti mk1 before now, wasnt consistent problem as you would have thought somtimes worse than others.