A4 1.9tdi 130 running like a bag of .....

[S4_dan]

My mates car runs lumpy on idle, and hesitates like mad under full throttle. Light driving and you can tell it's surging. He put it into a garage and they came back as injector 1 was faulty. He got the car back and I advised fitting a new injector loom instead. Because I advised, I ended up fitting one! lol.

Anyway, the car has slightly improved but not by much. Now there are no DTC's at all, the injector code has gone.

I've scanned the car again tonight, no DTC's stored. However, the injector quantity in group 13 varies accros the four injectors. 1 = +1.45, 2 = -0.21, 3 = -1.65, 4 = -0.25

The temp gauge takes an age to get up to 90 so we are looking for the correct part number to replace that.

As he has recently bought the car, the PO had stated that the car was 'chipped', but we have no proof.
I'm thinking now along the lines of a poor map/chip.

So, once we've tried a new genuine CTS, what else should we be looking at?

Cheers.

 

[pauldazzle]

PD130 will take an age to get to 90c if left at idle. Take it for a quick 3 or 4 mile run then look in VCDS engine measuring blocks to see what the ECU is getting from the CTS. If the gauge & VCDS are showing 90ish c then the CTS is probably ok.
I'd be having a look at the MAF readings & doing some MAF logging in VCDS. Remember there are several engine sensors that can be at fault without throwing a code.

 

[S4_dan]

he drove 25 miles to my house and it was in the middle between 50 and 90. VCDS was showing the temp at 63.9 and it didn't move up at all.

I unplugged the maf and that made the car drive a lot worse, but didn't do maf logs then as I was at his house and not mine and didn't have my laptop with me.

On idle, the car is really lumpy. The Injection quantity is all over the place. Not all consistent. Only two were within spec, cylinders 2 & 4.
From 3k rpm the car really hesitates and it struggles to get up to 4k. No smoke out of the back though, so I'm leaning towards fuelling issue, and again, even possibly the map/chip.

 

[pauldazzle]

Temp thing could be the stat stuck open which is very common on these cars. Unplugging the MAF trick doesn't work on Audi's.

 

[Chrismawa]

Faulty injector loom?

 

[pauldazzle]

He's changed that already.

 

[adamss24]

Pull the rocker cover and check camshaft...

 

[mattyb6]

1st thing change the temp sender and stat for a oem one

2. Like adamms24 said give the cam a good look

3. Read the stickies and do the Mr muscle mod

Then if it's still running crap it could be tandem pump, boost leak etc

But start with the cheap and easy fixes

Give it a service and whack some injector cleaner through

 

[sumo]

Sticking EGR valve will cause very bad running and no fault codes. Blank it off and see if it runs better.

 

[Paul @ Unit 9 Remaps]

It seems everyone forgets about cam shafts these days' PD lumps suffers bad with worn ones' it's a good shout

 

[S4_dan]

I remember looking at the cam shaft whilst replacing the loom, running my finger over the lobes and it was all smooth. (I will rmeove it again for a double check though. Will it wear across the full lobe or score it in the centre only?

I've done Mr Muscle before on my own cars. Will give it a go on this one. I've told him to blank the EGR off, so hopefully he has ordered a kit.

What the tandem pump and where is that located? What's it's purpose etc?

It's had injector cleaner through it after I fitted the injector loom.

Cheers.

 

[mattyb6]

Tandem pump is at the back of the head under the boost pipe

It runs of the cam too create a high pressure pump for the diesel
The servo also runs from the pump too

Basically the gasket (rubber/metal) fails and diesel and oil leak from head

It's relatively easy to remove and check if it's leaking, and a new gasket it about £7 from tps

I'd buy both kinds of gasket and it saves removing the pump again

If it's leaking you have less fuel pressure which could be one of the problems

A new pump is £250 if it's Fooooked

 

[S4_dan]

He is coming over today at 11 am, so I will check the Tandem pump for leaks.

This was the vcds scan of injectors:

 

[mattyb6]

Scan again if no faults I'd run so premium diesel through it and some good injector cleaner
If that doesn't work try terra clean, or a new injector loom which is about £60 I think

If not is it smokey? Could be an injector seal???

 

[S4_dan]

I fitted a new injector loom last week.
It's had some injector cleaner through it already...Forte diesel system treatment.
No DTC's present at all since fitting new loom.
He doesn't use supermarket fuel, only Shell or Jet
No smoke at all.
Turbo Actuator is free and working.

Driving with my foot lightly on throttle and car will drive nicely up to and over 3k rpm.

Put my foot down a bit more and that's when the hesitation starts, the more the pedal is pressed the worse the hesitation is.

 

[mattyb6]

Got to be turbo veins or fuel pressure
Hmmmmmm

Not vacuum leak/ boost leak

Where you based Dan ?

 

[S4_dan]

My mate is in York. I'm near Thirsk.

Turbo actuator is working....unless the veins are not but lever is?

No boost leaks that I/We can hear.

 

[mattyb6]

Could be just two vacuum pipes the wrong way round

Paul @ unit 9 on here can do boost leak tests
And he's in Durham

 

[Paul @ Unit 9 Remaps]

unbelievable the amount of boost leak tests we do. usually find them with in a couple of minutes. More than welcome to come and get a test done

 

[mattyb6]

It's bugging me now lol
Want to know what the problem is

Is there any play on the turbine shaft?

 

[demus]

Sounds really like a lack of fuel to me, have you changed the fuel filter, is the pump in the tank running ok, you can hear it run for a second or two when the ignition is switched on..

 

[Paul @ Unit 9 Remaps]

you mention in post 1 about it apparently been mapped. maybe try a standard file on

 

[demus]

Could well be the problem..

 

[S4_dan]

To me it, I feel it's under fuelling. Where could I get hold of a standard map from? I have MPPS from when I put a remap on my B6.

I will double check the vacuum lines. Is there a comprehensive diagram anywhere please?

Cheers.

 

[S4_dan]

Will get a fuel filter for it and see if that helps.

 

[demus]

To me it, I feel it's under fuelling. Where could I get hold of a standard map from? I have MPPS from when I put a remap on my B6.

I will double check the vacuum lines. Is there a comprehensive diagram anywhere please?

Cheers.

There is but I'm ******** if I remember where, it's pretty straight forward though, a supply down to the front from the vacuum pump, tee'd off the master cylinder feed.
Down the front it feeds three valves, egr, boost, and anti shudder, think there is a reservoir too, like a big ball valve float.
Does the anti shudder valve close and open when you shut the engine off?
It relies on vacuum in the system for a couple of seconds after the engine has stopped, if there is a vac leak it may not work properly.
Watch yours to see how it works..

 

[mattyb6]

To me it, I feel it's under fuelling. Where could I get hold of a standard map from? I have MPPS from when I put a remap on my B6.

I will double check the vacuum lines. Is there a comprehensive diagram anywhere please?

Cheers.

Haynes manual has one mate that I used and it's easy to follow

 

[S4_dan]

FIXED!! T'was the fuel filter. At the same time I put a Blacksmoke map on it. Pulls really nicely now with only a slight hesitation. Using VCDS I believe the MAF isn't 100% so he will replace that anyway.

So, a combination of injector loom and fuel filter.........

Cheers for everyones input.

Much appreciated.