Hesitation under load

[HitmanAU]

Hey guys,

Loving the 225 so far but it has developed an issue on very hot days (35-45 deg C) when aircon is on.
When ever I put my gut down hard the revs build then power does then comes back then dies and continues to donut sporadically until I back off.
Does it in all gears too.
If I then turn the aircon off the car still does the same thing.
If I clutch in and boot the revs it won't cut, it's only under load.

Also if I drive in the same heat without the aircon on at all, it doesn't seem to do it.

Plugs are new, coils and injectors are not.
It idles a little lumpy sometimes too but idle revs are always at 800rpm.

Any ideas? I'm thinking running some injector cleaner through it just as an interim.

 

[Brigsy]

Injector cleaner wont do a lot - The injectors will need ultrasonically cleaning or renewing. Rough idle indicates they are past their best, i have seen them cause misfiring on boost when in need of a clean so may be the issue.

 

[Red21]

Does the road speed increase inline with engine speed especially in 4th?

 

[DaveL485]

Does the road speed increase inline with engine speed especially in 4th?

ECU detecting clutch slip and backing the power off?

 

[HitmanAU]

Does the road speed increase inline with engine speed especially in 4th?

Certainly does. It's not the clutch slipping.
The strange thing that's got me stumped is it's fine without the aircon on.
Eg this morning, I gave it the clappers and drove it really hard to work (I start at 5am and live in the hills [emoji2][emoji2]) on boost all way to redline and it never missed a beat, same thing yesterday. Both days no aircon.

The aux belts were done not long ago so it won't be them. This ones got me.

I'm going to run a injector cleaner through to see if it clears the lumpy idle, no places open this time of year here to do injector cleaning plus it's about $200aud to get it done.

 

[DaveL485]

Is your alternator charging OK with the AC on?

 

[andybond]

ECU detecting clutch slip and backing the power off?

the r26 certainly doesnt do this.

 

[andybond]

I'm going to run a injector cleaner through to see if it clears the lumpy idle, no places open this time of year here to do injector cleaning plus it's about $200aud to get it done.

Wasting your cash buddy.

The injectors are around £160 in the uk for 4 new ones.

Have you got a ODB2 code reader ?

 

[Red21]

Had an interesting problem on a 165 Megane yesterday which the customer reported surges in the power delivery.
I eventually found the intercooler leaking under boost but it was not picked by the ECU as boost control fault because it had been "Re mapped" so all the factory parameters had been over written
I not saying this is what is wrong with your car but it just puts another spanner in the works.
One item that can affect the driveability of the car and is also part of the AC system is the Tri function pressure switch on the small pipe coming from the condenser.
This switch shares a common 5volt feed with other sensors & can corrode due to its location and thus cause various issues.

 

[HitmanAU]

That's what I thought but it's a fiver for the cleaner so can't hurt.

I'll test with aircon on tomorrow as 37 degree day here.
I just chucked a new battery in too a week ago as the last one was leaking acid everywhere!! Took half a KG of bicarb soda to neutralise the acid puddle in the battery tray, couldn't believe how much was there.

Alternator output not checked under load yet. I'll put a multimeter on it and see.

Only scanner I have is a toss tech system from my Skoda but I think it can still read ODB2 codes. I'll have to see I guess, or buy CLIP tool off ebay

 

[andybond]

@Red21 suggestions are a very good shout.

 

[HitmanAU]

Had an interesting problem on a 165 Megane yesterday which the customer reported surges in the power delivery.
I eventually found the intercooler leaking under boost but it was not picked by the ECU as boost control fault because it had been "Re mapped" so all the factory parameters had been over written
I not saying this is what is wrong with your car but it just puts another spanner in the works.
One item that can affect the driveability of the car and is also part of the AC system is the Tri function pressure switch on the small pipe coming from the condenser.
This switch shares a common 5volt feed with other sensors & can corrode due to its location and thus cause various issues.

Definitely not a boost leak, I know what that's like and it's not doing it at the moment and I've been hard on the power for past 2 days.

This pressure switch you speak of may be the culprit though. Corrosion not usually an issue here in Australia as much as you boys in UK as where I live we don't get ice and snow and no salting of roads. That being said, if it's near the battery tray then maybe the sulphuric acid dripped down onto it???

Where would I find this switch?

I really need to get a workshop manual for this car.

 

[HitmanAU]

the r26 certainly doesnt do this.

I wasn't aware any car did this

 

[HitmanAU]

Thanks again for the help guys.
Red21 - do you just strip and replace the 5v feed or the whole switch

 

[Red21]

The corrosion is caused by water so it could still be affected.
As you say the battery was leaking I would check the wiring around that area very closely as the acid will damage the wiring.
The AC sensor is replace along with the wiring connection if damaged, but as it is part of the AC I would strongly advise that it is replaced by an authorised refrigerant handler just in case the one way is stuck open.

 

[DaveL485]

What caused the battery leak? It's not overcharging is it?

 

[HitmanAU]

What caused the battery leak? It's not overcharging is it?

Previous owner put a cheap ass battery in that are known to leak bad out of the top cap.

I have a friend in car battery business (Yasua Century) and when I told him a had a leaky battery he says "let me guess, it's a power charge" which it was.

New battery does not leak at all.

 

[HitmanAU]

Just an update for everyone...
I had aircon blasting on the hour long drive home today and the car didn't hesitate one bit!!
I even had 20KG of chocolate in tow with me so car was lugging itself plus 100KG of weight.

My verdict on this at the moment due to the fact I haven't done anything except filled tank with a full tank (light was on) of 98 octane from a different Servo to normal, is it was a bad batch of fuel.
After Christmas I'll rip out the filter and replace it.

Where is it on the 225?

 

[andybond]

You won't be taking the filter out!

It's in the tank !

 

[HitmanAU]

Oh I figured there was an in tank on the pump but surely there is another one between that and the rail