AWD stalling at idle

[xenoAWD]

Hi guys, just after some advice. Our TL AWD, which we've had for more than 10 years, occasionally stalls when idling e.g. waiting at traffic lights. It just cuts out and you need to re-start it, but it re-starts straight away.

We had some issues a couple of years ago with stuttering while accelerating, but this may have been bad fuel and the addition of injector cleaner seemed to fix this. But I think this is a different problem.

Today I drove it, and even while cruising this time is seemed to be retarded for a split second, but then got going OK. I recently took the car to a Mits dealer, they put the computer on it but no fault was shown. They also cleaned the throttle body, adjusted the fuel/air mix and idle speed, and replaced the air filter which they said was completely blocked. The car still has the problem. They said the next thing to check would be the spark plugs, throttle position sensor, etc, etc.

The car just ticked over 200K's, up till now it's been a fantastic family car, but I don't want to keep throwing money at it, I'll just get rid of it unfortunately. My son, a P-plater, currently drives the car, and this issue can be dangerous in some situations, so any advice would be much appreciated. Fuel filter perhaps?

Thanks guys in advance.

[an observer]

For some months I've had an intermittment miss under mild throttle. Several tanks of 98 made no difference. Mechanic reckons change the plugs next, this will be the second change, the long life plugs on the back cylinder bank each are more expensive and fiddly to get to.

I'd suggest you try that as well, at 200k if they haven't been done at least once before they are definitely overdue now.

[xenoAWD]

Thanks an observer. Yes I was told the same thing, but other mechanics I spoke to said this probably isn't the problem as it would happen all the time. I think the rear plugs were changed back around 100K.

My next thing was to change to 98 octane as you did, to see if it made a difference. Also someone mentioned the fuel filter? Hopefully these make a difference, the plugs would then be the next thing.....and possibly the last.

[an observer]

Let us know how you go. Mine is going in for a service this week, and see if they can fix the intermittent miss.

[xenoAWD]

Will do, thanks

[leadfoot6]

Hi guys, just after some advice. Our TL AWD, which we've had for more than 10 years, occasionally stalls when idling e.g. waiting at traffic lights. It just cuts out and you need to re-start it, but it re-starts straight away.

Over a 2 year period I had similar problems which got worse.....stalling more and more often until it became very very frequent and eventually dangerous.

It was the Air Flow Meter(AFM) which did ultimately show an error light on the dashboard.

A local mechanic plugged in his sensor and showed me the codes and gave me free advice - see TIP below.

2nd hand AFM 6 months ago.....not a single instance of stalling since.

You might be in the early stages of the AFM about to fail.

TIP>> If AFM does actually fail and the car wont restart, pull the AFM connector which will allow the car to be gently driven for a few days until you can source a replacement.

Cost $87.....Priceless.

[xenoAWD]

Thanks leadfoot, I'll look into this as well.

Did yours stall predominantly when stationary, or also when cruising?

Cheers

[leadfoot6]

It only ever seemed to stall on light throttle at low speeds when moving, not at cruising speeds where more throttle was used, or revs were up a bit even if on closed throttle.

On the final day, I got the check engine light on the dashboard first thing that morning, it was stalling continuously until I was able to coax it to higher speeds, at which point it did not stall.

But when back to idle or low speed, it started behaving very badly.

It was lucky I was able to coax it to the mechanic for the code readout.

I live in the country, so lower traffic density allowed me to "work around" the problem to some extent.

If this problem had have become bad in city traffic, it would have been a tow truck job.....until the mechanic told me to unplug the AFM sensor plug, which allowed me to drive gently for 3 days whilst waiting for the replacement sensor to arrive in the mail.

Whilst the sensor was unplugged, it did not stall once.

[xenoAWD]

^^^ Thanks for the info. Our car seems to stall mostly at idle e.g. waiting at traffic lights, but I've also noticed stuttering at low throttle as you mention.

Anyway, see how we go because if it comes down to a process of elimination, I may not be bothered with it. Hopefully it gets resolved soon.

[WytWun]

If it seems to lose power while moving, the ignition coil could be suspect (I had a somewhat similar experience which was eventually traced to the coil).

If the issue is mostly at idle or just off idle, and your fuel economy has deteriorated a bit, the condition of the oxygen sensor might also be worth checking if it isn't known to have been replaced.