sirspooney
New member
hay i have a fiat bravo 1.2 16v sx and its miss firing could anyone help me pls
Technical bravo 1.2 miss firing any help pls
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Technical bravo 1.2 miss firing any help pls
what you checked so far? are you getting a spark on all plugs?
sirspooney
New member
ive changed the plugs and ht leads and air filter.
cheers
on another not do u no if 1.4 lower springs will fit my 1.2 cheers
cheers
on another not do u no if 1.4 lower springs will fit my 1.2 cheers
springs will very probably fit, the springs on my car were labelled for the 1.2 1.4 1.6 1.8, i've had them on a 1.8 and 1.6 so far.
misfire could be coil related, thats always a good place to start.
also check all the rubber hoses connected to the inlet manifold or throttle body for any leaks.
also could be injection system related, such as an injector failure
could also be compression related if a valve or piston ring is worn.
misfire could be coil related, thats always a good place to start.
also check all the rubber hoses connected to the inlet manifold or throttle body for any leaks.
also could be injection system related, such as an injector failure
could also be compression related if a valve or piston ring is worn.
Is it on missing one or two cylinders? My coil pack died and I was down to 2, can try having a listen and swapping them over to see what difference it makes (though guarantee it won't do it when you want it to until it goes completely 
). Good old injector cleaner is also worth a go in case one's blocked. These are cheap and cheerful before looking into bigger problems.
). Good old injector cleaner is also worth a go in case one's blocked. These are cheap and cheerful before looking into bigger problems.sirspooney
New member
tried that a few times didnt seem to do anything. it sounds like its slutering tho
the problem will very likely be down to a faulty injector or coil. there is a simple 'no tools' test you can do at home to identify which problem you have. its as simple as this-
1. start engine and let car idle
2. remove the ht lead from sparkplug on cylinder1, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
3. remove the ht lead from sparkplug on cylinder2, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
4. remove the ht lead from sparkplug on cylinder3, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
5. remove the ht lead from sparkplug on cylinder4, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
6. turn off engine.
7. look at results of the test. all 4 leads should have caused a noticable drop in revs. if only one of the 4 cylinders didnt cause a drop in revs you have a faulty injector on that cylinder. if a coiled pair of cylinders (1&3 or 2&4) both caused no change in revs you have a coil failure. if you happen to be one of the very few people who had no chance in revs on cylinders 1 and 2 OR 3 and 4, you should check that the ht leads are connected correctly and possibly consider a double injector failure.
this test isnt gospel, any result could also be due to a bent valve, worn piston ring, even a worn camshaft or a bent conrod, or a slipped timing belt etc etc could create the same result. BUT, it is much much more likely that you have a single injector failure or a coil failure, and this test can help you identify such problems. also, if you've had any work carried out recently (such as belt change) its important to say because it has an influence on the probability of different causes.
do the test and let us know how it goes, depending on what the results are we can advise on the next steps to take.
1. start engine and let car idle
2. remove the ht lead from sparkplug on cylinder1, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
3. remove the ht lead from sparkplug on cylinder2, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
4. remove the ht lead from sparkplug on cylinder3, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
5. remove the ht lead from sparkplug on cylinder4, do you notice any change in revs (a slight drop in revs when lead removed)? note the effect and replace ht lead.
6. turn off engine.
7. look at results of the test. all 4 leads should have caused a noticable drop in revs. if only one of the 4 cylinders didnt cause a drop in revs you have a faulty injector on that cylinder. if a coiled pair of cylinders (1&3 or 2&4) both caused no change in revs you have a coil failure. if you happen to be one of the very few people who had no chance in revs on cylinders 1 and 2 OR 3 and 4, you should check that the ht leads are connected correctly and possibly consider a double injector failure.
this test isnt gospel, any result could also be due to a bent valve, worn piston ring, even a worn camshaft or a bent conrod, or a slipped timing belt etc etc could create the same result. BUT, it is much much more likely that you have a single injector failure or a coil failure, and this test can help you identify such problems. also, if you've had any work carried out recently (such as belt change) its important to say because it has an influence on the probability of different causes.
do the test and let us know how it goes, depending on what the results are we can advise on the next steps to take.
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anyway its a 1.2 model, so my mystic tealeaves tell me its a coil problem. bet its running really rough and started without warning for no apparent reason? i love coil packs
jug said:
sorry thats wrong the firing order is 1 3 4 2 so a coiled pair is 1&4 or 2&3
sirspooney
New member
hay i tried ur test today and the revs dropted on all four cylinders. and it was miss firing wen i bought it cheap. so what do u surjest? i notice on second one along from the left it didnt do it as bad as the other 3 ??
ok, so possibly the injector is faulty on cylinder 2. if the difference was noticable then its easily bad enough to cause misfiring. next you need a multimeter and access to the injector wiring loom connector (right hand side of fuel rail usually). if the 1.2 connector is the same as the 1.6 (and most cars) it will have 5 pins, the centre one is earth, the other 4 are for the injectors. call them 1, 2, 3, 4, 5. measure the resistance across 1 and 3, using the black terminal of the multimeter on 3. note the ohms. now test 2&3, then 4&3, then 5&3. these 4 test will show you the condition of each injector. all 4 values need to be very similar to each other, if one appears to be lower than the rest you can be fairly confident that you need a new injector. if all 4 test the same then an injector blockage (rather than internal fault) could be to blame and i'd try 2 bottles of redex with less than a fiver of super unleaded, very strong mix i know but it works better.
sirspooney
New member
ok ill try that, im having a auto electrian to have a look at it tomo to see wot he can do with it hes the dogs
