Surging Issue - Map itself?

You can't diagnose a fuel pump off the water temp. If you just accelerated up a long hill pulling a caravan (for the purpose of the exercise, not that anyone in their right mind would be pulling a caravan on this forum), the water temp goes over 100 and your fuel pump is shot??????

Water temp will cycle up and down a bit in traffic as the fans kick in, thats how the fan switch works. It cuts in at 104 degrees and off at 95 degrees, or thereabouts.

That bad pump would probably last forever in a std car but just couldn't keep up with the fuel demand of a chipped one.

Gavin
 
I see what you're saying.. but I'm just going on what everyone else has wrote.

How come Fran's APS company were able to put it down to the fuel pump?

What does the '49' group actually measure? Is it water temp as someone else said, or....?
 
There are to parts to the temperature sensor; one part that feeds the dash pod whic is software bias so that it reads 90 when the actual temperature could be anything between 80 and 100, and the seond part which feeds the ecu. The ecu gets to know exactly what the temperature is so that it can adapt the fuel mixture etc based on the temperature. Group '49' is the actul figure that the ecu 'sees' from the temprature sensor, so is a more acurate reading to look at. However it does fluctuate depending on the ambient temps and what load the car is under at the time.
 
*eek*

What would be best for me to tell the garage then? 'suspected' fuel pump, BUT...

The only thing I can do, is give them the symptoms, hope they can dig something out with VAGCOM and save my car!
 
Yes Jimmeh, you can say you suspect it but I'd get them to use a device to test the fuel pressure... I looked at your VAG-COM logs and they were similar I must admit. So did it have no error codes under then engine block when you plugged your VAG-COM in?

By the way when I plugged my VAG-COM multiple times it didn't come up with any errors when my fuel pump was failing... So you can't rely on that tell you im afraid.. VERY FRUSTRATING!
 
I think the best clue you might have got from VAG-COM would be if you managed to have it run weak long enough that the ECU flagged up a fuel trim problem.

The other thing you might have seen if you logged the lambda and saw that lean out.

Gavin
 
Nothing mate, no. VAGCOM brought up (under code Engine - 01) the "16486 - Mass Air Flow Sensor (G70): Signal too Low" issue.. but that was all. TBH, I haven't got a registered version of VAGCOM thinking about it.. so this wouldn't have carried out the full tst. BUT, the engine coding did only bring the MAF issue, that was all. (which has dissapeared now)

The car's booked in at the garage first thing Tuesday morning. I just hope their experienced with the whole VAGCOM/diagnosis side of it all. they're engine specialists, but not nesacarily VAG.

h100vw, see here (or here) for the log.. note the lambda didn't give any readings at all.

what is meant by 'lean out'? Fail?!
 
With the lean out comment, I would expect the lambda output to go lean as the fuel supply failed to keep up with the demand.

Not sure why you get 0 on your logs for lambda. I often see a couple of blocks that have lambda on them.

The airflow looks healthy at 200.

Not sure what else to offer at the moment.

Gavin
 
sorry to sound thick but how do your get thme readings on the console like that?? what other things can you measure?
 
See FRAN-S3's comment above..

"One thing that will help point to it if it's running lean which I was cars tend to run hotter then usual. To see what yours it access the ecu climate control trick thing which tells you on your climate your exact water temp... Hold down re-circ button and up arrow in car.. Youll see 001 I think, use temp + till you get to 049 then press recirc button again to access it. In here mine was reading between 98 and 99 when warmed up!"

It's pretty simple. I think there is a guide somewhere with the other menu readings etc.. clever stuff.

I wonder if I was reading the wrong code then h100vw, would it be worth me trying another run focusing on the lambda?
 
im fairly certain the codes were posted 3 or 4 months ago by Ashs3 or Grathies
 
I'd have a look and see what else is there. Go up through the blocks one at a time and see what you find.

I would agree that a weak mixture would cause cylinder temps to rise but I doubt you notice it in the water temp. The thermostat keeps the water temp constant when the car is moving. If you were sat in traffic, the mixture would be fine as the pump would have no problems keeping up with demand.

The easiest way to diagnose a duff pump would be on a rolling road with an AFR probe in the exhaust.

Gavin
 
do youknow or remember what the name of the thread would be?
 
Picked up my S3 Sat.... WOW WHAT A DIFFERENCE!!!!!!!! ITS FLIPPING MENTAL, the boys at APS were superb - a big shout out to them for sorting my car out! Remaps are only 300 + VAT which I thinks a bargain compared to what others charge.. Plus they do a full diagnostics before hand. But wow what a difference, im loving it. Such a smooth but powerfull map all the way through the range. Very impressed, had a 'play' with a z4 and left him in my rear view mirror!!!!

So yes very much enjoying the new power, and having to be carefull how I use it! Plus my DIS is now reading 28mpg round town which it never did before... 25 at best on motorway! All that from a failing fuel pump, amazing!
 
glad you like it Fran, the smile will last for ages:eek:)....... most maps do cost approx £300-400 and all will do a full diagnostics before as they do not want any failed components to be blamed on them.....
 
Arr ok cool. The Revo one is quite expensive then at £500 + VAT.
 
if you look in the right places you will get it a lot cheaper Fran..... my CC only cost £325inc VAT... even cheaper at GTI international as they were offering 40% off which dropped it below the £300 mark. I think there is some le-way on mapping costs as there are so many about and its a 100% mark up once they have funded the software unless they are dealers/named distributors, still going to have a decent amount of profit to play with
 
1animal1 said:
I think there is some le-way on mapping costs as there are so many about and its a 100% mark up once they have funded the software unless they are dealers/named distributors, still going to have a decent amount of profit to play with
Click to expand...

I never thought of it this way.. Good point!

We all know my car has the map (which I didn't know about..) but when I went to get a quote for a REVO (when I found out I already had it) it was likely to cost around the £500 mark as fran-s3 rightly says.
 
1animal1 said:
if you look in the right places you will get it a lot cheaper Fran..... my CC only cost £325inc VAT... even cheaper at GTI international as they were offering 40% off which dropped it below the £300 mark. I think there is some le-way on mapping costs as there are so many about and its a 100% mark up once they have funded the software unless they are dealers/named distributors, still going to have a decent amount of profit to play with
Click to expand...

No worries thanks. It's ok I got APS to remap mine for £300 + VAT and im more than happy with it. So smooth right the way through, they tweak them individually I believe. Top service!
 
hey Fran im not slating them at all.....and happy for ya that you are infact enjoying it...makes the S3 a better car, most would say what it should have been

They may tweak it if you have other mods... if you havent they are more likely to code in a preset version.....
 
Yeah true. Well they saw my silicone TIP, forge blow re-circ and greenpanel filter so I think they may have. They said it certainly repsonded like one of the better ones they've had.. Prob because most of the sensors have been changed recently LOL!
 
im trying not to rain on your parade doood, i got told exactly that too:eek:D
 
stop raining on my parade!!!!! :moa:
 
My car was dropped off at the garage this morning. I gave them the following:

Symptoms
- Misfires (present on diagnostic print out from VAGCOM – See attached)

- O2 Sensor(s) & Catalytic Converter – “Failed or incomplete” on VAGCOMs ‘View Readiness’ screen (see attached)

- Great loss in power, noticeable difference

- Sounds like a tank

- Running lean and smells very hot after steady runs + plus poor MPG.

- Boost leak reported from previous VAGCOM logs (would be good if this could be cleared)
Click to expand...

I figured I'd better write down the issues, as they're never going to remember what had to be done, and I'd have the car returned with (no doubt ) half the issues still there.

Everytime I hear the phone I get all excited! :(

I will keep you updated.
 
They've had the exhaust off, they've checked the CAT, no problems.

Can't be sure if they've had it on VAGCOM or similar yet, it was a very quick phonecall..

They want me to collect the car this evening/tomorrow morning an give it 24hr's use... they're installing a datalogger that will track all the happenings in the time driven.

Hopefully this will allow the misfires, running rich issues etc to show.
 
Having dropped the car back with the garage this morning (After 24hrs driving), I handed over the 'chip' and hoped for the best (for it to have found something!)

One thing he did find (straight away..) was that I had been speeding (105mph, to be exact *whoops*), but it all the flags and issues started to appear.

He shouted me over, and pointed out a "fuel trip malfunction". Seeing this, brought a smile to my face. Fran, it's likely I'm having the same problems as you! They're too do a pressure test today and check out the O2 sensor and fingers crossed, that 105mph, will turn into 145mph! :) (kidding! I'm only kidding... )
 
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