Disconnected the maf and it went worse!

[stu9]

On an 03 C5 2.0hdi

I did it a few weeks ago, and was shocked, when I connected it, I was better but still sluggish and s t, but after a bugger up with my ecu and Whippy fixing it, I'll put the lexia on tomorrow and see if there's any codes to be had. I've reading about some ways to test it so will try that too.

Has anyone else disconnected theirs and it went worse

[andy5]

Are you sure you mean MAF? The device measures the amount of air measuring the engine, then an ECU calculates how much fuel to add.

Without it there can be attempted calculation, but it will not be as reliable for the whole range of operating conditions. Some tuners might want to remove its slight restriction to the airflow, but they will add a different type of sensor and reprogram to match.

Did you instead want to remove EGR?

[andy5]

I cannot edit that from my mobile.

now done

[stu9]

Are you taking the p**s....I know what the bloody maf is!

The egr's allready blanked

[Gibbo2286]

Are you taking the p**s....I know what the bloody maf is!

The egr's allready blanked

Unnecessary venom, he only asked.

I can't think what you expected to gain from disconnecting a vital part of the engine management system.

Or did you mean it went tits up after disconnecting and reconnectiong?

[Mandrake]

Why would you be surprised that it ran worse with the maf disconnected stu ? It's there for a reason.

With no MAF/MAP sensor the ECU can only estimate air flow based on temperature, throttle opening and engine rpm, which is not very accurate.

[stu9]

I disconnected it to see if it was it was fkd....it cant be as it ran worse

I did it because it's bloody sluggish and tried a few diffirent things and thought I'd try that, but i guess after trying the maf, it's fine, dont know what to do/try now

[Mandrake]

I still don't see the logic behind disconnecting a vital piece of the engine management system and concluding that because it runs worse with it disconnected that it must be ok ? Sure, it's doing something, that doesn't mean its working properly...

It's as if you had a faulty spark plug lead that was causing an intermittent misfire, then concluded that because disconnecting the plug lead entirely made the engine run even worse that the plug lead must be ok... makes no sense...

[Gibbo2286]

Mine was like that but it was the turbo not working properly due to a punctured vacuum pipe, fixed that and it now is as good as new.

[stu9]

I still don't see the logic behind disconnecting a vital piece of the engine management system and concluding that because it runs worse with it disconnected that it must be ok ? Sure, it's doing something, that doesn't mean its working properly...

It's as if you had a faulty spark plug lead that was causing an intermittent misfire, then concluded that because disconnecting the plug lead entirely made the engine run even worse that the plug lead must be ok... makes no sense...

Because after reading in a few places that sometimes slugishness especially below 2 grand can be faulty MAF and since it only take literally 2secs to discconnect and try it, I did.....it ran a bit worse like that, so might not be it but emailed the results to someone else who's looking into it