Hi all. I have a 53 1.4 focus. It has an annoying flat spot / misfire when pulling away. It's as if the fuel/air mix is wrong and seems like it runs on 3 cylinders for a few seconds then normally picks up... Also if you lift yoyr foot off the accelerator and then back on that also gets rid of it. It's more annoying than anything when pulling away from a junction as it can take maybe 3/4seconds to pick up. It doesn't do it every single time, but often enough though. It had a new coil pack about 2years ago and has also had news plugs and leads so I'm half ruling those out. What else could it be.?? Also if you park it with its nose down hill it can sometimes take 5/6 seconds to start. .. If up hill then the problem never seems to arise? Any help is greatly appreciated

Hi all. I have a 53 1.4 focus. It has an annoying flat spot / misfire when pulling away. It's as if the fuel/air mix is wrong and seems like it runs on 3 cylinders for a few seconds then normally picks up... Also if you lift yoyr foot off the accelerator and then back on that also gets rid of it. It's more annoying than anything when pulling away from a junction as it can take maybe 3/4seconds to pick up. It doesn't do it every single time, but often enough though. It had a new coil pack about 2years ago and has also had news plugs and leads so I'm half ruling those out. What else could it be.?? Also if you park it with its nose down hill it can sometimes take 5/6 seconds to start. .. If up hill then the problem never seems to arise? Any help is greatly appreciated

Anyone?

Hi all. I have a 53 1.4 focus. It has an annoying flat spot / misfire when pulling away. It's as if the fuel/air mix is wrong and seems like it runs on 3 cylinders for a few seconds then normally picks up... Also if you lift yoyr foot off the accelerator and then back on that also gets rid of it. It's more annoying than anything when pulling away from a junction as it can take maybe 3/4seconds to pick up. It doesn't do it every single time, but often enough though. It had a new coil pack about 2years ago and has also had news plugs and leads so I'm half ruling those out. What else could it be.?? Also if you park it with its nose down hill it can sometimes take 5/6 seconds to start. .. If up hill then the problem never seems to arise? Any help is greatly appreciated

MAF (Mass air flow) sensor

perhaps try spraying with specific foam cleaner,

Also upgrade induction filter

Check spark plugs aswell.

Any signs of blue smoke?

As Lenny states above & electrical contact cleaner with a cottonwool bud for cleaning the M.A.F. sensor - VERY CAREFULLY !

Thanks for the reply guys. I'll try giving the maf a clean and see how it goes. Can I get away with using brake disc or carb cleaner on it??

Electrical contact cleaner or isopropyl alcohol are the best products to use for M.A.F. sensor cleaning

Hi

Another issue with the zetec engines is that water would pool around one of the spark plug chambers, This can also be linked with a engine core plug leaking.

If there is water in one of the spark plug chambers it will cause misfiring etc etc as the electricity passes through the water.

I would also check the condition of the spark plugs

Also Check the condition of the Ignition leads, if one of them is cracked and arcing the power will be down on that lead,

Hope this helps

Jamie

Thanks for the reply guys. I'll try giving the maf a clean and see how it goes. Can I get away with using brake disc or carb cleaner on it??

You don't have a MAF, Focus Petrol engines from 2002 use a TMAP sensor.

whats the difference between a MAF and a TMAP?

You don't have a MAF, Focus Petrol engines from 2002 use a TMAP sensor.

Does the MAF measure the amount of the air going through and the TMAP measure the Temperature of the air going through?

Just wondering as its always good to know these things lol!

Sonic, your right about the MAF, the TMAP sensor sits in the inlet manifold and measures the intake air temp and the manifold vacuum.

Temperature and Manifold Absolute Pressure (T-MAP) sensor

Sonic, your right about the MAF, the TMAP sensor sits in the inlet manifold and measures the intake air temp and the manifold vacuum.

Temperature and Manifold Absolute Pressure (T-MAP) sensor

Well I'm glad I'm on the right tracks there lol! Can the TMAP sensore be cleaned using special cleaner and if so what one is best? also is there any way to test the TMAP sensor the same way that a MAF can be tested.

Technically the measure the same thing but interpreted differently.

By running an electrical current through a wire you know how hot it is, by changing that temperature you alter the voltage due to resistance, with some Maths you can work out what the temperature is and or how much air is flowing past it, if its covered in crap it will reduce the effect of air temp so buggers up the readings to the ecu

Technically the measure the same thing but interpreted differently.

By running an electrical current through a wire you know how hot it is, by changing that temperature you alter the voltage due to resistance, with some Maths you can work out what the temperature is and or how much air is flowing past it, if its covered in crap it will reduce the effect of air temp so buggers up the readings to the ecu

Thanks Darren, Great Info there. Its amazing the way that the sensors are designed on modern engines and how it all works together compared to the older engines back in the day.

Thanks Darren, Great Info there. Its amazing the way that the sensors are designed on modern engines and how it all works together compared to the older engines back in the day.

engines were much better before 2005 on most manufacturers definitely before 2002 on all manufacturer's

only one oxygen sensor in exhaust and a catalyst.

some had map sensor others had a MAF

proper distributor cap and HT leads no coil packs,

Cars had LSD instead of ESP

Turbos had bleed valves instead of EGR Valves

DPF's didn't exist and the sports model wasn't just a red stripe on the interior.

engines were much better before 2005 on most manufacturers definitely before 2002 on all manufacturer's

only one oxygen sensor in exhaust and a catalyst.

some had map sensor others had a MAF

proper distributor cap and HT leads no coil packs,

Cars had LSD instead of ESP

Turbos had bleed valves instead of EGR Valves

DPF's didn't exist.

Totally agree with you Lenny. It be interesting to see what its like in 10 years times. :)

Roll the clock back further before fuel injection and you will find mechanics that actually looked for problems and solved them.

This world where you plug a computer in then write off a multi thousand pound car is such a wasteful world.

Course I'm not knocking all of them, but a lot are a little to quick to give up because of the amount of electronics in cars now,

if E.U. every gets there way we will all be driving electric cars then the pleasure of real driving will be like the dodo

if E.U. every gets there way we will all be driving electric cars then the pleasure of real driving will be like the dodo

aye well you know what you need to do to stop that happening then! ;)

Id probably be keen on a hydrogen powered car but not an "electric" one, amazes me how folk seem to forget that we burn tons of coal an gas to make that lecky here. an the first person to start talking about giant windmills and such like can just keep that to them selves! :P can you imagine the number of these things we would need to have along with huge new reservoirs for pumped storage to power every car in the UK the only good thing is we would all be working less since itll take two days to get to work :D

We could become freelance environmentalist's and work from home or well anywhere we want on environmental issues 😁

Or call ourselves economists as we save money driving electric cars 😂

hi again guys.

eventually got around to going to clean the maf sensor but it doesn`t have one. Any other thoughts.

thanks

My car had a flat spot until the alternator failed now its gone!