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        General >> Give/Need advice to/from others >> Diconnecting MAF Sensor ?
        
(Message started by: lesterlad aka Rodders on Aug 18^th, 2010, 6:37pm)

Title: Diconnecting MAF Sensor ?
Post by lesterlad aka Rodders on Aug 18^th, 2010, 6:37pm

Can anyone advise me as to what should happen with engine rev's if the MAF sensor is disconnected ?

I have unplugged the MAF when engine is hot and cold but there is no noticeable change in engine revs when I do this.

I have developed a tiny problem at tickover, the revs increase by approx 50revs every second then drop back again to 950.

Just wondering if the MAF is kaput.

If I switch the aircon on the revs remain rock steady (non cc)

Title: Re: Diconnecting MAF Sensor ?
Post by gozz on Aug 18^th, 2010, 7:35pm

Sounds like a mucky idle valve Rodders,if you unplug the MAF when it's idling,absolutely nothing happens to the revs I have found.
GOZZ.

Title: Re: Diconnecting MAF Sensor ?
Post by Mike H on Aug 21^st, 2010, 10:59am

That' right it shouldn't, it just allows the computer to use closed-loop fuelling (compare input and output gasses); if discconnected forces it to resort to open-loop fuelling. Apparently it does that anyway until everything is warmed up.

As a matter of interest I had a little bit of erratic idling speed after I'd put on a new MAF and filters and the new exhaust, sometimes be >=1,000 rpm, another time, normal, but has since settled down to consistently normal. Could be the PCM needs time "re-learning" the new conditions. (?)

Have you disconnected the battery recently?

Title: Re: Diconnecting MAF Sensor ?
Post by lesterlad aka Rodders on Aug 21^st, 2010, 5:02pm

on 08/21/10 at 10:59:13, Mike H wrote:

Have you disconnected the battery recently?

Battery has never been disconnected ever since i have had the car (21/2 yrs)

Title: Re: Diconnecting MAF Sensor ?
Post by Mike H on Aug 23^rd, 2010, 11:43am

I just wonderred whether the PCM had lost its memory ;D

Title: Re: Diconnecting MAF Sensor ?
Post by lesterlad aka Rodders on Aug 23^rd, 2010, 7:48pm

I'm going to try Gozz's suggestion, (Idle valve), I need to locate a known good one first, I don't want to start messing and taking things to bits that use electrickery or knowing my luck I'll end up with a non runner and then we get into the realms of withdrawal symptoms. :o

Title: Re: Diconnecting MAF Sensor ?
Post by gozz on Aug 23^rd, 2010, 8:10pm

Rodders.
I sometimes need to clean mine when the engines start 'hunting',take it off and give it a good blast of carb cleaner and a shake,then a drop of light oil on the spindle.
GOZZ.

Title: Re: Diconnecting MAF Sensor ?
Post by tonyboy on Aug 23^rd, 2010, 8:12pm

Do you replace the gasket , or use a silicone gasket ???

Title: Re: Diconnecting MAF Sensor ?
Post by gozz on Aug 23^rd, 2010, 10:20pm

tonyboy.
They have O ring seals.

Title: Re: Diconnecting MAF Sensor ?
Post by Tompion on Aug 23^rd, 2010, 10:22pm

The 2.3 has a figure of 8 rubber gasket set into the manifold. They seem to stay flexible I usually leave it in place & give it a wipe of grease.

Title: Re: Diconnecting MAF Sensor ?
Post by lesterlad aka Rodders on Aug 23^rd, 2010, 10:23pm

on 08/23/10 at 20:10:26, gozz wrote:

Rodders.
I sometimes need to clean mine when the engines start 'hunting',take it off and give it a good blast of carb cleaner and a shake,then a drop of light oil on the spindle.
GOZZ.

Ah, Hunting, that's the word I was rattling my old grey matter to try and remember, that's what it's doing but only very slightly (50 revs every second)

Tonyboy has a good point there, new gasket or some silicon gasket in a tube ?
edit:
already answered above (I'm a slow typer) ;)

Title: Re: Diconnecting MAF Sensor ?
Post by gozz on Aug 23^rd, 2010, 11:04pm

Rodders.
I thought you wrote "a slow type" for an instant,they are confined to the Fens,it is not wise to be slow in Leicester,you know,the quick and the dead etc ;)
GOZZ.