not a toyota problem but will ask anyway

[ChrisStarletGT]

my gf ford puma is knackered on idle it missfires every so often then stops then does it again as it does this the rev needle twitches up and down im thinking idle control valve but they 70 quid and also been told it could be tps which also aint cheap any1 else had sum experience with this on a zetec s engine i know it wrong for me to ask on here but im always on here with my gt and the ford forums cant answer shit cheers guys and girls

 

[Texx]

I'd start with the ignition coil, it's common for them to give trouble.

 

[Skalabala]

What air meter type does it have? AFM or MAF? this could also do it.
You can plug a laptop into the ecu and get rpm reading, if the laptop says it is idling higher than what the car is actually doing then TPS might be a problem.
Checked the plugs and plug leads? As Texx said, because the ecu will try to compensate for the problem and give a bad idle.

 

[ChrisStarletGT]

Im doing the disconnect the battery ecu reset at the moment see if that works then i will know the tps is knackered if that doesnt work im gonna take it to garsge for diagnostic plug in there is so many things it could be what i hav researched on net that if it idles high its tps but mine drops so thinkin icv but who knows lol

 

[spuddy]

Crank sensor or equivalent, would explain the rpm needle twitching and the meesed up timing causing back fires.

 

[ChrisStarletGT]

the battery off ecu reset didnt work was ok at first then it came back so it now at ford getting a live feed diagnostic to pin point exactly what it is all place your bets now winner gets a rep lol

 

[ChrisStarletGT]

£78 diagnostic and they dont know what it is coz it didnt do it when it was there but as soon as i picked it up it did it again got to take it back in the morning and the service manager gonna look at it will they charge me again?

 

[SupaStu]

Kinda sounds like the tps, is the revs all over the place? Get one from a scrappy to check it.

Get the rest of the stuff mentioned above to be sure.

 

[Texx]

A typical Zetec ignition coil failure starts off with a slight misfire or hesitation under load as you take up drive and pull away, it's a very common problem with the Mk1 Focus and more so with the 1.6l. A new coil from Ford is around £35 and aftermarket coils are readily available at around £15.

Last time I spoke to the local Ford dealer to get an ignition coil for a '99 Focus they had 37 in stock, seems to give give an indication of how often they fail.

 

[MARK@CMBAUTOS]

A typical Zetec ignition coil failure starts off with a slight misfire or hesitation under load as you take up drive and pull away, it's a very common problem with the Mk1 Focus and more so with the 1.6l. A new coil from Ford is around £35 and aftermarket coils are readily available at around £15.

Last time I spoke to the local Ford dealer to get an ignition coil for a '99 Focus they had 37 in stock, seems to give give an indication of how often they fail.

x2 replaced heapz of them ull see the hair line cracks on it but watch u dont round the little torques when removing it

 

[studoc72]

x 3 its the coil

 

[ChrisStarletGT]

wouldnt do it again all day today went to ford wasnt doing it so i took it out for a long drive and it still wouldnt do it so got to take it back if it does it again it did it a little bit tonite when i was driving into car park going slow so maybe it is the coil pack

 

[MARK@CMBAUTOS]

wouldnt do it again all day today went to ford wasnt doing it so i took it out for a long drive and it still wouldnt do it so got to take it back if it does it again it did it a little bit tonite when i was driving into car park going slow so maybe it is the coil pack

Usually it if it is the coil the wet/ damp weather will affect it more

 

[ChrisStarletGT]

I was thinkin it air temp sensor coz it was quite cold today and it wasnt doin it but the i unplugged the sensor and it still didnt do it so dont prob the coil