A Reduced Engine Performance light came on last year (April maybe). Also, the car stared to jerk a little when I took off, not massively but still enough to notice. I gave it to my mechanic at home and he done a diagnostic on it. Said there was an air flow problem message so he got a new MAF Sensor.

That didn't work at all. I got a 2nd MAF sensor in the fear the first was faulty. Still the same light came on and jerky starting.

I then processed to plug the MAF sensor out and it is running fine. Although a engine management light is on all the time and I get a message re coolant but once I plug it back in all them messages disappear and engine management light is off.

However, I continue to drive with it plugged out and it is running fine save for Engine Management light being on.

Do you have any idea what the problem could be?

 

Could be an intake leak somewhere. The MAF code was just telling your mechanic that the MAF reading doesn't match to where it should be, not that the MAF was bad. A lot of people unnecessarily replace MAFs.

 

Thanks Dingus.

Any reason why it works perfect when the MAF sensor is plugged out?

M

 

Your car is no longer trying to correct the error using the MAF reading because it is not there

What year is your car?

 

It is 2015.

is it a big job to find a potential leak and get it fixed?

Thanks - you're the first person that has said something that sounds like you somewhat on the money. Thanks.

 

It all depends on your capabilities. I personally have a cheap smoke machine (pretty much an automotive vape) that I can hook up to an intake hose and it will fill the intake with smoke @ like 2psi or so and leak out of a cracked hose or another leak. Free for me to do, but I am not sure what a shop would charge to diagnose this, although I think it is generally around 1 hour of labor. MAF error codes like this could have a wide range of causes so it really depends on the diagnostic.

You can also try the flame in a can technique where you take a can of starter fluid or any flammable aerosol and spray accurately near intake hoses and see if you notice an increase in RPMs in a certain area. This would mean the gasses are getting in the hose and being used as fuel.

I had a crack on a piece of corrugated intake pipe before that I would have never found with just visual inspection alone.

 

Hi,

I brought it to the garage yesterday. They are saying the following messages came up,

1) DPF is clogged
2) Flaps that open and close are ceased
3) 3 sensors are broken (including MAF seansor).

Quotation of over €2,000 to remove DPF and clean it and replace faulty sesnsors.

I am just confused as the car is running absolutely fine save for the small jerking and thw odd time "Reduced Engine Performance" comes up.

When I plug the MAF sensor out it works fine (bar a check engine light being illuminated).

Does that seem right?