MAF question(s)

Ok, so my TD4 has been running low on power for a while, and searching the forums, it would seemed that there was a possibility that I killed my MAF by fitting a K&N air filter. Everything was running fine, then 2000 miles after fitting the air filter there was a sudden drop in power, and now lots of smoke when starting with lumpy tickover etc etc.

Today I went out and disconnected my MAF and it makes no difference to the running of the engine. Possibly slightly better if anything. Can I assume then that the MAF is kaput?

If it is I'm thinking of replacing with a pierburg from roverron, is this a straight swap or will I need the synergy unit as well to make it work?

Also would the K&N filter damage the pierburg?

Any advice appreciated.

Cheers

Hi. From my experience with my old TD4 which had a rover Ron MAF you will need a MAF box from him to convert it or use a synergy 2 which was the option I went for as you will gain a nice increase in power and be able to use his MAF's. Don't be tempted to buy a cheap oem MAF though I tried this at first and they don't work the only ones I would fit are Rover Rons and the genuine Bosch one.

What symtons are you getting regarding low power as when I disconnected mine it made a huge difference.

Dave

Check out for split hoses first.

Dont know about the k&n , but if you get a ron box you can use a pierburg maf , you will need the special torx bit to remove the oem bosch maf from the car

I've seen no hard evidence that k&ns kill mafs! From description I'd look for split hoses first too

I've already replaced the two intercooler hoses for nice silicone ones from DPH. I hoped that would cure the issue, but it didn't.

Am I right in thinking that by disconnecting the MAF and it making no difference to the performance, that it was already running on default, therefore proving that the MAF was knackered?

One thing it does seem to have done is stopped the amount of smoke coming out of the exhaust at start up though.

Hopo said:

I've already replaced the two intercooler hoses for nice silicone ones from DPH. I hoped that would cure the issue, but it didn't.

Am I right in thinking that by disconnecting the MAF and it making no difference to the performance, that it was already running on default, therefore proving that the MAF was knackered?

One thing it does seem to have done is stopped the amount of smoke coming out of the exhaust at start up though.

Click to expand...

Certainly on the td5 it improves it cos it puts it on its default map! Not a td4 expert tbh

Diesel Do said:

I've seen no hard evidence that k&ns kill mafs! From description I'd look for split hoses first too

Click to expand...

As told a couple of times already in the past, I experienced the same thing when I put a K&N filter in mine (this was back in 2001), a few weeks later I had troubles in revving up and taking off etc... but at that time this phenomaena was not explained/known yet as it is now so I kept driving it for not knowing better, until the time I entered the motorway and a truck almost hit me as I couldn't make way fast enough, so I wents straight to the garage and the headmechanic testdrove it, already by leaving the parkinglot he said the maf is gone, they replaced it and no more problems, when I now clean the filter and re-oil it again I do it very sparsly and, fingers crossed, so far no problems anymore, I have to add though that I clean the maf on a yearly basis since I read this on this forum it was done by some. So, was it coïncidence or really caused by the filter I don't know but it did happen to me as well. (And as this was/is also mentioned on other forums and other brands forums I think that where there's smoke is fire ???)

willo said:

As told a couple of times already in the past, I experienced the same thing when I put a K&N filter in mine (this was back in 2001), a few weeks later I had troubles in revving up and taking off etc... but at that time this phenomaena was not explained/known yet as it is now so I kept driving it for not knowing better, until the time I entered the motorway and a truck almost hit me as I couldn't make way fast enough, so I wents straight to the garage and the headmechanic testdrove it, already by leaving the parkinglot he said the maf is gone, they replaced it and no more problems, when I now clean the filter and re-oil it again I do it very sparsly and, fingers crossed, so far no problems anymore, I have to add though that I clean the maf on a yearly basis since I read this on this forum it was done by some. So, was it coïncidence or really caused by the filter I don't know but it did happen to me as well. (And as this was/is also mentioned on other forums and other brands forums I think that where there's smoke is fire ???)

Click to expand...

I honestly don't know, I have heard of it before, but if it's that much of an issue surely they'd have to address it? It may kill nearly knackered ones, it may just be coincidence? There's always product bashing between manufacturers and suppliers, mafs are considered a service item by some manufacturers now, cos they don't last forever. Could it be that when cars come to the age when people start tinkering the MAF is on its last legs anyway? Buggered if I know

That was my thought Diesel Do. Mine has done 98000, so it's quite possible MAF was on it's last legs anyhow, again may be coincidence like in Willo's case. Willo, it was your post re K&N I found on the search that got me thinking it may be the MAF.

Can anyone confirm that if my factory fitted MAF was working then I should notice a difference one way or the other if I disconnect it? The fact it's hardly made a difference now it's unplugged suggests to me that it wasn't working. Surely if it was working I would notice a difference. Do these things just go or do they degrade over time?

I think i'll probably end up replacing it anyhow and If I have to fit the Pierburg MAF then I guess I'll have to get a synergy to make it work. Oh well!

Thanks for all the advice so far. keep it coming.

I had the same simptoms as a knackered MAF

1. Big pause before the car moved when setting off
2. Rough running between 1000 - 2000 rpm
3. Unplugging the MAF made no difference

It turned out that the issue was solved by excess crap in the EGR value. Worth trying before changing the MAF as its cheaper!

Vertuas said:

I had the same simptoms as a knackered MAF

1. Big pause before the car moved when setting off
2. Rough running between 1000 - 2000 rpm
3. Unplugging the MAF made no difference

It turned out that the issue was solved by excess crap in the EGR value. Worth trying before changing the MAF as its cheaper!

Click to expand...

He's got an egr bypass already ???

willo said:

He's got an egr bypass already ???

Click to expand...

Ahhhh, sorry, I missed that bit