MAF sensor???

[driverjgp]

Just recently when I start the car from cold it splutters to reach idle, it then gets to idle then its fine.

Then tonight it took the second start to start with the above description, could this be the MAF sensor playing up? other times it is fine its only now and again it gets like this. The car drives fine, the type of car I have is below.

Thanks in advance.

[Simon]

Hmmm.

Could be many things. MAF is one of them, as is fuel-suply or even a sticking throttle body to name but a few.

Is the throttle cable on the throttle body free-moving? I'm not sure where the MAF sensor on a V6 is but after someone more knowlegable has told us where they are I'm sure it's worth a clean to see if these rectify the problem.

Of course, I may be talking utter :rubbish:but hopefully someone more techy can help out as well...

[Ti Rich]

The KV6 engine doesn't have a MAF sensor - it's only the diesel models!

[Simon]

The KV6 engine doesn't have a MAF sensor - it's only the diesel models!

It's got something similar. I forget what it's called now so i used MAF instead. It's used to help regulate the air/fuel mix according to the density of the oxygen in the incomming air in the KV6.

[Ti Rich]

On the petrol models i thought the fueling map was modified from the Lambda sensor in the exhaust. Air flow, is calculated by measuring the intake temperature and then the manifold pressure by the MAP (Manifold Absolute Pressure) sensor - is that what you mean?

Sometimes the MAP sensor can stop working if there is oil vapor in the sensor tubing, it might be worth removing the tubing and blowing it out.

I might also be completely wrong and if so sorry!!

[Simon]

Yeah, i think the MAP sensor is the one i'm getting at as this can become (as you say) a bit gunked up.

All in all, to aid the original post about a troubled idle speed could this be a cause do you think?

Had another thought on this.... there was a thread about an inconsistent idle speed.... I'll see if I can find it.

[Simon]

Here we go

http://www.the75andztclub.co.uk/forum/showthread.php?t=710

This is one of those long-winded threads but if you study it carefully reading through all the posts then it will higlight a few key things worth looking at.

Hope this helps! :lol:

[driverjgp]

Here we go

http://www.the75andztclub.co.uk/forum/showthread.php?t=710

This is one of those long-winded threads but if you study it carefully reading through all the posts then it will higlight a few key things worth looking at.

Hope this helps! :lol:

It Idles fine it runs fine, its the starting thats the problem, when you turn the key it splutters coz it is struggling to reach idle, after a second it makes idle then it is OK and other times it starts fine, it is under warranty but it is one of them intermittent problems so I'm trying to get a rough idea what it could be then I'll take it to the dealer and tell him its a such a such problem.

[Simon]

Just thought that maybe one of causes of the idling problem on that thread may be causing your intermittent starting problem.

I'm clutching at straws now, but how about fuel pump(s)? Maybe one is 'sticking' slightly every now and then causing temporary fuel starvation. Once the pump is going tho, the 'sticking' friction has been overcome and it therefore runs ok.

Or how about the automatic choke control? :confused:


Sorry I'm a bit vague. :o

[driverjgp]

Just thought that maybe one of causes of the idling problem on that thread may be causing your intermittent starting problem.

I'm clutching at straws now, but how about fuel pump(s)? Maybe one is 'sticking' slightly every now and then causing temporary fuel starvation. Once the pump is going tho, the 'sticking' friction has been overcome and it therefore runs ok.

Or how about the automatic choke control? :confused:


Sorry I'm a bit vague. :o

I haven't got a clue it seems OK today, thing is you don't no when it is going to do it so you don't no when look for the fault, 99% of the time it is fine.

[Keith]

Just recently when I start the car from cold it splutters to reach idle, it then gets to idle then its fine.

Then tonight it took the second start to start with the above description, could this be the MAF sensor playing up? other times it is fine its only now and again it gets like this. The car drives fine, the type of car I have is below.

Thanks in advance.

First and easiest job to do is clean the IAT valve with meths or brake cleaner
When this valve gets cruddy you get anything from eratic idle to a jammed throttle.