Frederic Nuyttens

Pajero sensor located next to MAF

Recommended Posts

Guys,

I've been breaking my brains over this one: On my 1999 Pajero there is a sensor mounted on a bracket next to the MAF. (see pic). It has no mechanical connection to anything. It just sits there. There is a little hole in the sensor that allows me to turn it left or right. When i do so, i hear the idle speed slightly going up or down. I tried different settings and the engine performs the best when it is disconnected. 

* Is this some sort of choke throttle sensor that was never mechanically connected to the air inlet ? Although EFI does this automatically i'd assume ?

* Some temperature measurement maybe ?

Disconnecting it doesn't even bring up the engine light. 

 

IMG_1281.JPG

Share this post


Link to post
Share on other sites

Seems like you have bigger problems than that, the thing you say isn't connected to anything is actually your MAF sensor as you can clearly see there is a big plug missing which should be connected to your MAF. So right about now your ECU is running a default fuel map which is usually limp home map since it is not getting input from the MAF. How long has it been like this?

Share this post


Link to post
Share on other sites

Thank God for that, you never can be too sure though as Ive seen dumber things than that.

Like a buddy taking his range rover all over the place because because it seem to have lost power and after a year of doing this and spending good amount of money. He resigned to the idea and just kept driving it as is. I had driven it many times too and it was low on powrt. Then one day I had a look under the hood and there it was bright as day right in front of the engine. The cam position senor on the left bank wire was totally cut and just lying there. 

I had an entire donor car sitting in my parking at the time so I just took one out from there and fitted that one and plugged it back in and car was back in action and still is to this day.

Share this post


Link to post
Share on other sites

MAF sensor controls the amount of air going in inside the engine. Means when you floor the throttle it will open valve wide to suck more air and then ECU reads that data to send more fuel to let your drive faster. I really doubt that in Pajero there is limp mode, however, when you disconnect and drive for a while you will get engine light as when you floor hard then the car might stall due to the rich mixture and less air. If you drive in grandmom mode you might not realize this MAF disconnected issue.

In this model Pajero this MAF is always an issue as it becomes loose and dirty over time. First get it cleaned properly with right anti-static spray (not WD40) and let it dry and then fix it as tight as you can and then strap this with two cable ties. Replacement is expensive above 2-3K and it's very hard to find good working one in scrap and still, it costs quite much.

Share this post


Link to post
Share on other sites

Hi @Gaurav yes the MAF sensors (vortex) are pretty expensive. I cleaned mine thoroughly a few weeks back with electronic cleaner spray, and it performs well. A new one was around 1600-1800 with the [email protected] guys. 

In my case when i disconnect it automatically brings on the engine check light and the car runs according to a default program setting. (no acceleration at all until you reach 2500rpm then it shoots up, but dies back immediately)

So back ontopic now: anybody has any idea what this sensor located next to the MAF sensor is doing ? (see on picture the one with green and white wire on connector).

 

TIA,

 

Fred

 

Share this post


Link to post
Share on other sites

Slight correction the MAF does not control the flow of air, it just measures how much air is being sucked in. The throttle body butterfly valve which is linked directly to the gas pedal mechanically via a cable and nowadays electronically in most modern cars is what controls the flow of air and then the IAC takes over this duty when your foot is off the pedal 

Share this post


Link to post
Share on other sites

Oops, I thought you asked for MAF.

Below one seems like an electrical connector probably to supply secondary power to MAF - it's just my educated guess.

Share this post


Link to post
Share on other sites

@Gaurav strangely enough it it mounted on the MAF bracket but is a complete standalone sensor. It looks actually very similar to a throttle position sensor, but it is clearly not. Will try to search one more time in the service manuals of the pajero.

Share this post


Link to post
Share on other sites
1 minute ago, Frederic Nuyttens said:

@Gaurav strangely enough it it mounted on the MAF bracket but is a complete standalone sensor. It looks actually very similar to a throttle position sensor, but it is clearly not. Will try to search one more time in the service manuals of the pajero.

Yes, exactly that's what I was thinking of doing as soon as I get free time. As service manual has an engine bay diagram and name of all components.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now