Hi. My 59 plate 1.6 zetec has developed an intermittent rough run, with some hesitation in accelerating. Ive read that a probable cause could be the MAF sensor. Has anyone had experience with this? Is it worth trying to clea it first? Is replacing it a diy job? And any links/ recommendations for the right part to get? I’ve looked on car part sights and there seems a lot of choice in price and manufacturer. Many thanks

I wouldn't waste money replacing any component unless there was some evidence that the component was faulty.

Just now, Tizer said:

I wouldn't waste money replacing any component unless there was some evidence that the component was faulty.

Thanks Tizer. Would you recommend giving it a clean?

24 minutes ago, Bazbluebadge said:

Thanks Tizer. Would you recommend giving it a clean?

Yes, it won't do any harm.

Getting under the bonnet. I can’t see a MAF sensor on the air intake. Is it the sensor past the air intake next to the throttle body?

There isn't a MAF sensor on this engine.

It does have a tMAP on the inlet manifold after the throttle body.

If its MAP sensor you're on about, I changed mine a month ago. Easy job. Take off the main air hose thqy goes from the the air filter to the throttle body for access, then the MAP sensor is just one torx screw. Undo that, unclip the electrical connection, clip new sensor in and screw it on. Put air hose back in place and off you go! I would recommend disconnecting the battery when you do this job. It ensures safety and it resets the long term trip computer meaning that your ECU will learn how to adjust fuel/air ratio based on the readings from new sensor. Once you've finished, i recommended turning the ignition to the first setting (electrics on but no engine on) and leaving the key there for 2 mins for the key and car to talk to eachother. Then turn off. Then fully turn on the engine and leave to idle for 10 minutes before driving anywhere. This helps the ECU manage idling fuel/air ratios before it attempts to do it with the engine under load while driving.

To be honest, might be worth taking your throttle body out too and giving it a wipe with a very slightly damp microfiber cloth to get any debris out of there and allow air to pass to the MAP sensor more easily. Ensure throttle body is 100% dry before putting it back in

7 minutes ago, Eli_P said:

If its MAP sensor you're on about, I changed mine a month ago. Easy job. Take off the main air hose thqy goes from the the air filter to the throttle body for access, then the MAP sensor is just one torx screw. Undo that, unclip the electrical connection, clip new sensor in and screw it on. Put air hose back in place and off you go! I would recommend disconnecting the battery when you do this job. It ensures safety and it resets the long term trip computer meaning that your ECU will learn how to adjust fuel/air ratio based on the readings from new sensor. Once you've finished, i recommended turning the ignition to the first setting (electrics on but no engine on) and leaving the key there for 2 mins for the key and car to talk to eachother. Then turn off. Then fully turn on the engine and leave to idle for 10 minutes before driving anywhere. This helps the ECU manage idling fuel/air ratios before it attempts to do it with the engine under load while driving.

To be honest, might be worth taking your throttle body out too and giving it a wipe with a very slightly damp microfiber cloth to get any debris out of there and allow air to pass to the MAP sensor more easily. Ensure throttle body is 100% dry before putting it back in

I got RIDEX sensor, boost pressure, from Autodoc.

£15.99

Item number: 161B0027.

Autodoc are good, stick your reg in and their recommended parts tend to be pretty accurate.

1 hour ago, Eli_P said:

If its MAP sensor you're on about, I changed mine a month ago. Easy job. Take off the main air hose thqy goes from the the air filter to the throttle body for access, then the MAP sensor is just one torx screw. Undo that, unclip the electrical connection, clip new sensor in and screw it on. Put air hose back in place and off you go! I would recommend disconnecting the battery when you do this job. It ensures safety and it resets the long term trip computer meaning that your ECU will learn how to adjust fuel/air ratio based on the readings from new sensor. Once you've finished, i recommended turning the ignition to the first setting (electrics on but no engine on) and leaving the key there for 2 mins for the key and car to talk to eachother. Then turn off. Then fully turn on the engine and leave to idle for 10 minutes before driving anywhere. This helps the ECU manage idling fuel/air ratios before it attempts to do it with the engine under load while driving.

To be honest, might be worth taking your throttle body out too and giving it a wipe with a very slightly damp microfiber cloth to get any debris out of there and allow air to pass to the MAP sensor more easily. Ensure throttle body is 100% dry before putting it back in

Great. Did it make a difference

5 minutes ago, Bazbluebadge said:

Great. Did it make a difference

Absolutely did. Idle is smooth and quiet, acceleration is fast and responsive, and fuel economy has improved. Definitely would recommend cleaning the throttle body at the same time as changing the MAP sensor if you go down that route.