HI, I have a mk4 cortina 1.3L with it s standard engine that has around 88000 km, it starts fine even in cold weather, and while chocked it misses a little but works, when the engine gets to temperature and i turn off the choke, it idles fine and at constant throttle it works fine too but as soon as i push the throttle pedal down the engine feels like it s gonna turn off, then it backfires 1 or 2 times and revs up....

I checked the spark plugs 2 of them where black and 2 where orangey i changed all 4 and spark is coming on the plugs. Could it be the timing is a bit off?? or the carb needs a service kit (I think that the carb never got off the engine).

P.S I have a small whole in the exhaust pipe near the gearbox and the fuel filter isn t always full could any of those effect??

 

That will be a Pinto engine I would think (OHC), it's worth giving it a tune up and checking the timing etc, by how you describe the plugs it's well deserved!

Ideally the plugs should be a chocolate brown colour indictating ideal fuelling, black sooty plugs are a sign of overfuelling but it's as well to see how it goes after a tune, then go from there.

But if you suspect you have a different carb, this will also cause problems, they could of fitted that from a 1600 model etc but on your smaller engine will cause it to run rich, if it's not been setup etc.

Martin

 

Hi
Just a few points observations. Get the choke off as soon as possible every time. The problem is likely to be the carburettor throtle pump diaphragm. The throttle pump (At leas I think that's what we used to call them!) injects a glob fuel when big demands are made such as throttle down/blipping etc to avoid the inevitible flat spot you are experienceing due to an over-lean mixture.

Might be worth a carb rebuild kit or maybe pick up a good known carb and just swap them over.

 

No martin it s a kent crossflow engine and the engine was never opened it s still factory including the carb

 

I have some carbs that where taken off working engines i ll install one of them and see how that goes if it works good i ll get a kit for it s factory carb

 

I would look to the carb first as it a fixed jet type with as stevo said a acceleration pump think you may have a transition problem with the change from idle jetting to main jet so give it a clean and /or service.

 

Oh right thats why I wasen't sure as they were avaliable with both, I wasen't sure if you meant the carb had been changed but scrap that as you say it's never been off.

Also noticed you mentioned exhaust, whilst obviously it could make a difference, I doubt it's going to effect your fuelling, the case could be different however it it were a modern setup, i.e. Closed loop as more oxygen will be present.

Martin

 

i did some work on it today, checked the ignition system the plugs and their gaps are good the distributor is ok to the coil has a slightly high resistance but it s delivering a strong spark so ill let it be for now.... the carb however was in a bad state i ha to clean it change one of the injectors cause it was so badly cloged i couldn t clean it properly and changed the diaphram (had to use a used one as it s sunday and couldn t find a replacement) also it wayyyyyyyyyyyyy tooooo much petrol so i fiddled with the adjustments too.

Now it runs great it has a steady idle and good throtle response though it still has a small blank part but i noticed that if i am not lead footed and press the pedal gently it won t back fire and accelerates smoothly i also fount out that the exhaust gasket (engine to manifold) is something of the past as there is a gap visible by the naked eye so it s a need to fix too

tomorow i ll get the gaskets and the diaphram and swap them hope it will cure it

 

please some one help me i need to buy a carburetor gasket kit for a 2l pinto engine but i cant find any if some one could forward an email of were to find them this would be a great help cheers

 

try:
www.purtonpower.com or www.demontweaks.com

i m not english but i bought from these sites so hope this helps

 

There is a typo in the first URL, he means www.burtonpower.com, which is who I was going to suggest.

Martin