Hi all, I've recently been experiencing poor/lumpy engine performance, poor MPG & I reckon its running a bit rich (the exhaust is black but not smoking/blowing etc). It judders under acceleration & doesn't pull like it used to. The sparks, HT leads & coil pack have all been replaced the still the issue remains. I decided to try & remove the MAG & give it a clean as suggested by some of the more knowledgeable members but I can't seem to find it. I can't find anything that looks like the pics of a MK4 MAF (with the wires in etc), the Haynes manual isn't any help either (it doesn't seem to have my engine bay layout). The front right area where it seems most people find the MAF is just the plastic pipe for the air intake & the cylindrical thing in the 2nd pic with the stainless steel collar around it just has what I would describe as a white valve that can be opened & closed for airflow I guess but nothing that looked like a sensor. :blub:




If anyone after looking at the pics of my engine bay has any suggestions they would be much appreciated.

Cheers

Your car WILL have a MAF being electronically controller by the ECU.

That bit you describe, must be the MAF... I'm not that clued up on the 1.25 engines, but I'm asuming the inlet to the engine is just under the airbox where that "sensor" is?

I'd pull the airbox off and have a look inside it, and clean it.

_________________
Daily isn't so Special. And it makes me sad.
Need space and time and I'll crack on with Jams si!

Catch me on Facebook as I'm rarely on here.

Cheers for the quick response mate. I'm sure it must be the 'MAF' but I couldn't find/see any of the 'wires' that others talk about & you see pictured on various Fiesta forums. (When people talk about chaning a MK4 MAF) The unit clearly seems to control the airflow because the white 'filter' like material is split in 2 segments that looks a bit like looking at half of an apple & you can open or close it using the mechanism at the rear of the unit. (Like a valve).

Frankly for the 5 years I've owned the car I've loved it's 'go kart' handing, it was amazing last winter in the ice etc but this issue is proper starting to p1ss me off.

the mk4 1.25s dont have a maf sensor, i rekon its the lambda thats causing your problems...... you can check if the ecu has any fault codes on these on the dash, what you do is....
1. put the key in the ignition but do not turn it
2. hold the reset trip meter button in
3. while still holding the trip meter button, turn the ignition on but dont start the car
4. keep the button held in until it reads "test" on the digital readout, then you can let go

it should make all the needles on the tach, speedo etc go right round then back down, then you keep clicking the button in to scroll through, it shows you stuff like, speed, rpm, battery voltage, how much fuel you have in the tank, if you keep clicking it will eventually get to fault codes, see what you get and post them up on here, some 1 will be able to help

_________________

Thanks mate, I'll give it a go tomorrow & report back.

Cheers

That looks absolutely NOTHING like my old 1.25 Zetec-S engine from my mk4 Fiesta :S

It's like you haven't got a plastic cover for the rocker and the airbox on mine sat to the right of the battery and was half the size which did not cover the exhaust manifold..

_________________
Rest in peace Ben "Jam" Elvin. Gone but never forgotten.

I know mate, lol. I've had a look on ebay & there are some engines that are identical to mine from the same model. I guess there must have been a method behind Ford changing the engine design?!?

The engine design is the same just the air box position changed

as stuff n that said, but if your car dont have digital clocks then it wont work. ( digital dials have the milage and trip meter on a digital screen rather than the tumbler type dials you got on a older fiesta).

also the picture on the sensor looks like the throttle position potentiometer. on the other side of the pipe there should be the quadrant for the throttle cable.

but i think the car must have a maf meter somwhere as ford would have to use a totally different ecu other wise and just using a lamda sensor is a no go area for emissons.

either way i think it would be a good idea to check the condition of your air filter if it hasnt been changed in a while as it could strangle the air flow.

_________________
To rebuild?

Hi all, I defo have the digital trip computer, the air filter is 12 months old, the sparks & coil pack 3 months & the HT have all been checked (1 was replaced at the same time as the sparks & coil pack for not sparking much at all). Maybe 1 of the other HT leads is toast?!?

I don't know if this will mean anything to anyone but as requested this is everything I pulled off the digital readout it diagnostics mode:
bulb r09 PASS
EE01 PASS
AC44 dAtE
5967 dtc
9359 dtc
000.0 spd E
000.00 spd
0000 tACH
153 FUEL
PETr EnGinE
045.5 P 090 C
12.3 bat
-0 1 LLU
069 LCd
-6 Cr
-6 16
-0 L5
-1 65t
-0 rdo
-0 r5t
-0 FL1
-1 6Cd
-0 HtL
82 PA
0A Pb
F0 PC
0C Pd
156 PE0
152 PE1
255 PE2
255 PE3
255 PE4
255 PE5
049 PE6
187 PE7

These settings were taken after a good 40 minute drive which included about 25 mins on a motorway.

HELP, lol

Oh & I've just noticed when I blip the throttle I get a short kinda swoosh sound for maybe a second or so...and the exhaust is definately blowing. After firing up the engine I put may hand close the end of exhuast & you can feel the gases etc not flowing smoothly. Although it sounds OK from the engine bay when running, it definately doesn't sound very smooth at the exhaust end.

5967 dtc
9359 dtc
these two are fault codes which is what you will need to be looking at
the mk4 fiesta bubble shape had a maf and airbox behind the head light thne on the mk5 (2000-20002)
have the central airbox and iirc no maf
it does sound like one of your lambda sensor is faulty

some of them have mafs some dont, if its a black plastic tube connected to the air box inline with the intake pipe with no wiring and no boxs on it, then its not a maf model and is meant to be without

but again some do have them