2004 TD4 Snapped MAF sensor connector

Have managed to get the connector off. Just driven it home and it has seemed to have released a few more horses. Engine light was a bit disconcerting though and was half expecting the thing to just shut down on me. So i guess a cleaning is in order for the sensor. Will have to get my hands on some of those funky hex drivers !

orangesherbert said:

Have managed to get the connector off. Just driven it home and it has seemed to have released a few more horses. Engine light was a bit disconcerting though and was half expecting the thing to just shut down on me. So i guess a cleaning is in order for the sensor. Will have to get my hands on some of those funky hex drivers !

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if you've found the maf disconnected has improved the performance it normally points towards a faulty maf

give it a nice clean first though before buying a new one

there is also threads on here regarding worthwhile modes,

ie , egr bypass, updated crankcase breather , cleaning inlet manifold , etc

see how u get in after you've given it a clean , with regards to performance

be gentle with it as it has a wire across the maf

not telling u how to suck eggs in any way

You can buy cheap replacements but who knows how long they'll last. I just fitted one to my car and I think Nodge68 did too.

gstuart said:

if you've found the maf disconnected has improved the performance it normally points towards a faulty maf

give it a nice clean first though before buying a new one

there is also threads on here regarding worthwhile modes,

ie , egr bypass, updated crankcase breather , cleaning inlet manifold , etc

see how u get in after you've given it a clean , with regards to performance

be gentle with it as it has a wire across the maf

not telling u how to suck eggs in any way

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Not a problem. This is all fresh eggs to me, so ...
There was definitely improved performance, not mind blowing, but it was there.
Ill take it easy when cleaning. Thanks a lot for your advice.

I was reading a bit more on the old MAF situation on here and dead spots were mentioned, and it reminded me that on my journey home when i was tootling along at 65/70 when i put my foot down a bit more, nothing happened. As if i was restricted from going any faster. Like a pit lane limiter set at 70. I will be reconnecting it tomorrow before i get round to cleaning it, but is this something to do with its default setting? Just thought id mention it.

After eventually tracking down the correct Torx drivers (5 point, not 6) i managed to to get the MAF out and give it a clean with some airbrush cleaner. Some muck did come off but it wasnt filthy.
Popped it back in, but because the engine light didn't go out i thought i had done something wrong, not connected it correctly or something. Then my friend said that the engine light may need to be reset.
Is this the case? Will i need to get this reset or have i just not reconnected it correctly?
Took it for a drive and it did feel better or just the same as when it wasn't connected. TBH i didnt really want to reconnect it as it has been so much better with it off. Much more urgent under acceleration.

If it runs better with the MAF unplugged, then it's goosed. Replacement is the only cure. Cleaning does nothing.

Nodge68 said:

If it runs better with the MAF unplugged, then it's goosed. Replacement is the only cure. Cleaning does nothing.

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Thanks for your honesty Nodge Ill look into a replacement. Cheers

orangesherbert said:

Thanks for your honesty Nodge Ill look into a replacement. Cheers

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The cheapo ebay mafs are superb. fit and forget -
The tech in a MAF is absolutely minimal compared with - say - 5 or even 10 years ago. SIMPLE devices.

Unless of course you read the dire consequences and total BS hype on 'ronbox' type sites.

Go for the cheapo - it will be fine.

Nodge is absolutely correct - if you unplug it and it runs better'er - it is fecked.

It's beyond me why you guys don't go for a maf less remap.

Ive one in my 75 now and I'm coming up to 100k since it was done on a car with 250k on it.

The remaps was cheaper than a genuine maf alone.

Took my car from 113bhp to 152 bhp. Rolling road proven several times now, and as it was an auto you can't actually get the true power off it. Serveral of the manual owners have been touching 160bhp with a mountain of torque also.

Contact these guys, I will be doing same for my td4 also. Agents the length of the country. Everything is 100% custom.
http://dynamic-ecu-tuning.co.uk

MacGyver said:

It's beyond me why you guys don't go for a maf less remap.

Ive one in my 75 now and I'm coming up to 100k since it was done on a car with 250k on it.

The remaps was cheaper than a genuine maf alone.

Took my car from 113bhp to 152 bhp. Rolling road proven several times now, and as it was an auto you can't actually get the true power off it. Serveral of the manual owners have been touching 160bhp with a mountain of torque also.

Contact these guys, I will be doing same for my td4 also. Agents the length of the country. Everything is 100% custom.
http://dynamic-ecu-tuning.co.uk

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It is WAY beyond me why you post such misleading 'information' and simply do not amplify your existing MAF to achieve virtually the same results.

A new MAF is dirt cheap so you are talking bollix really..
Instead, you are conned into paying GOOD money for some voodoo Wooooooooooo

Enjoy -

https://www.landyzone.co.uk/land-ro...ects-for-the-so-inclined.304017/#post-3800861

Joe_H said:

It is WAY beyond me why you post such misleading 'information' and simply do not amplify your existing MAF to achieve virtually the same results.

A new MAF is dirt cheap so you are talking bollix really..
Instead, you are conned into paying GOOD money for some voodoo Wooooooooooo

Enjoy -

https://www.landyzone.co.uk/land-ro...ects-for-the-so-inclined.304017/#post-3800861

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Number 1. Dude. Chill, it's a forum of enthusitic owners.

Number 2. Well done that's a great diy job We call that in Ireland the maf bypass. Many doing similar for a decade in L series cars to varying degrees of success. I'm colour blind. And don't attempt any wiring at all. How bad? I bought a green 406 and tried to Polish it was black Polish as I thought it was black. =(

Number 3. Such information is not misleading. It allows for dual mapping akin to synergy boxes and the like without the need for a maf compensation unit. I liked the choice of doing away with the maf totally, the ecu being only clue of any change and also my insurance company will only cover ecu remaps not any other type of modifications.

Joe_H said:

It is WAY beyond me why you post such misleading 'information' and simply do not amplify your existing MAF to achieve virtually the same results.

A new MAF is dirt cheap so you are talking bollix really..
Instead, you are conned into paying GOOD money for some voodoo Wooooooooooo

Enjoy -

https://www.landyzone.co.uk/land-ro...ects-for-the-so-inclined.304017/#post-3800861

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And that is more rubbish.

You will only get more power out of a diesel engine if you put more diesel into it. The amount of diesel injected is governed by the maps in the ECU.

One of these maps is the smoke map which limits the amount of fuel injected given the air flow detected by the MAF given the engine's RPM. So you are right in that if you amplify the MAF's reading the smoke map will allow more fuel.

However, the smoke map (alone) is not the one that will govern performance increases in an engine - that is controlled by the torque map. So if you amplify the MAF it only has the effect of disregarding the MAF because the map will basically never be used. That is exactly the same a mafless map except that you have not addressed the torque map so its pointless.

Hi, just found this post looking for info on what i thought was the maf / air intake sensor, that i now dont know what it is, (the one on the plastic induction pipes at the front left of engine) i have a snapped wire at the connector and have recently replaced turbo and exhaust, i have more lag in low rev range, and a whistle (sounds like a permanant wastegate noise) will this be because of the broken sensor wire/connector??

Petepye said:

i now dont know what it is, (the one on the plastic induction pipes at the front left of engine) i have a snapped wire at the connect

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It's the boosted air temperature sensor, which the EDC uses to calculate fueling for the engine. This sensor wasn't fitted to earlier engines, but is on the later ones. If the wire is broken, then it "might" make a difference, but often owners don't notice any difference if the sensor is connected or not.

Nodge68 said:

It's the boosted air temperature sensor, which the EDC uses to calculate fueling for the engine. This sensor wasn't fitted to earlier engines, but is on the later ones. If the wire is broken, then it "might" make a difference, but often owners don't notice any difference if the sensor is connected or not.

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Ahhh ok, is it possible to replace wiring or just solder it up and see how it goes?

Thanks for the info Nodge, much appreciated

Just repair it with solder and insulate.

Nodge68 said:

Just repair it with solder and insulate.

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Git it soldered, also whilst bro-in-law was soldering i found a pipe had come off the turbo causing the whistle and noticible lag, popped that back on and no more whistle or major lag xD

Thanks for the help