This might be a silly question, but we've had a few hot days this last month. When the weather's hot, the car seems to drive much better. Smoother, quieter. Is it me, or is there something related?
Sounds a little backwards to what I normally hear.
I usually hear stories of how cars drive better in winter, with the colder air.
If you are getting better engine performance at the moment I say just enjoy it!
Perhaps a faulty temperature sensor or similar?
Well they should be smooth all the time, you just get a bit more kick when the air is colder and denser.
IC engines give more power when the air is dense and cool (and dry) as more oxygen in the charge gives a bigger bang.
Used to be simple back in the old days. If your car ran better on warm dry days (ie ran less well when it was damp), then something was going bad in the HT electrics- usually distributor cap or HT leads.
Minis (the old A Series engined ones) and WD40 used to be pretty inseparable due to the distributor being located at the front of the engine, right behind the grille.
Might be the same with your P38- if your HT leads are breaking down or you have tracking at the coils, you'll get a misfire on maybe as few as 1 cylinders. That's not always easy to hear but will have an effect on performance.
As Aragorn says, a failing sensor may also cause the engine to change to a default strategy and run less well.
Orangebean wrote:
Minis (the old A Series engined ones) and WD40 used to be pretty inseparable due to the distributor being located at the front of the engine, right behind the grille.
Yeah... driving on the motorway behind a lorry in heavy rainfall. When finally had a chance to overtake and hit the throttle, the hickups came.
Don't tell me about it.
I remember sticking the leads through a rubber glove then stretching it over the dizzy cap on a mini,, never got wet after that 👍
no10chris wrote:
I remember sticking the leads through a rubber glove then stretching it over the dizzy cap on a mini,, never got wet after that 👍
That was one of the better fixes Chris. Always looked a bit weird with a bright yellow Marigold stuck on the front of the motor though.
I was impressed that they designed the A Series with the same number of ht leads as fingers in a glove. It's as if they knew...
Orangebean wrote:
no10chris wrote:
I remember sticking the leads through a rubber glove then stretching it over the dizzy cap on a mini,, never got wet after that 👍
That was one of the better fixes Chris. Always looked a bit weird with a bright yellow Marigold stuck on the front of the motor though.
I was impressed that they designed the A Series with the same number of ht leads as fingers in a glove. It's as if they knew...
Better than that silly cover they designed,, my mum was pissed when one of her marigolds went missing,, I've never told her to this day.
Aragorn wrote:
Perhaps a faulty temperature sensor or similar?
Interesting you mention a faulty temperature sensor.
At the moment, i get a book code. No fault code listed on my little diagnostic thingy bob so i assume it's a hevac code that needs to be read by nanocom or such like. The book symbol comes on at exactly the same time the temperature needle gets to half way (normal temperature). If i switch off and back on again, the book goes and doesn't come back. Unless.....i leave the car standing for a few hours and it cools down then the book comes on again when the temperature gets back to half way. As i say, i don'thave the proper diagnostic to tell me whats up but through googling, i'm lead to believe that theres a water temperature sensor (part number STC3256) on a pipe under the dashboard, just to the left of where your left leg would be while driving. Could this be a likely source?
Doubt it, that's the sensor that tells the HEVAC that the coolant in the matrix is hot enough to turn the fans up and start blowing hot. I would suspect you've got an iffy temperature blend motor. When started from cold it will try to open the flaps fully to give you warm air, as the engine heats up it'll need to close them down and if it fails at that point, then you get the book symbol. Totally separate to the engine electronics though so wouldn't affect the running.
^ what Gilbertd says!
The only sensors directly related to atmospheric conditions are:
Engine fuel temperature sensor
Coolant temperature sensor (the one on the inlet manifold)
Intake air temperature sensor
MAF (Mass airflow sensor)
I see. Car blows hot and cold when asked tho. Is this related to that? Can have different temperatures at both sides. Aircon don't work tho. I think it just wants gassing. Clutch kicks in and motor works.
If it needed gassing the clutch wouldn't kick in as the pressure switch wouldn't allow it to. Maybe one or both blend motors will only travel part way so you can get heat but not cold? Needs plugging in to see what the actual fault is.
ah, i see. so clutch working and a/c light flashing indicates that it's working and doesn't need gassing. worse case scenario new blend motors then. Plugging in would be nice. think someone on here lives about an hour away from me but i can't remember who.
AC light flashing? What AC light? Do you mean that you have the AC Off button pressed in to cause the light to come on? In which case, the AC won't work as the button does what it says, it turns the AC off.
Morat is the guy near to you, or nearer than most of us anyway.
A/C light flashing means that car is unable to reach selected temp without active aircon
When light is on a/c is off.
Temp is set to low. When I start car, ac light flashes on and off for a bit. I assume it's to tell me that the car can't achieve the temperature I've set without me switching the a/c on. If I switch the a/c on (light off) it doesn't get any colder although the engine works slightly harder and everything appears to be running as it should. Except for the lack of stone cold air.
Don't bother with any of the buttons, just poke AUTO and leave it to get on with things for itself. If it doesn't get cold when on Lo, then it is probably low of gas but there may be enough in there for the compressor to kick in for a while.
If the centre of the A/C pulley is spinning the clutch has engaged - the small pipe should get hot, and the large one should get very cold (but not freeze up with ice etc).
If the large one is cold, then the evaporator inside the car should also be cold.
If they both feel the same, something isn't right and no refrigeration is actually happening. Maybe someone has bypassed a pressure switch, or the switch could be faulty. I wouldn't run it like this though as the gas also moves the oil around the system to lubricate the compressor.