OVER FUELING PROBLEM!

[vw754]

just been to independant vw/audi garage who put there diagnostic equipment on and took it for a road test VERDICT: Over fuelling slightly but we dont know why,no faults have been thrown up,injector readings:0-.75 -0.42 0.66 0.52 mg/str he said these are good,coolant sensor is at 86.9 which is ok,everything is ok but we dont know why its overfuelling...so if you guys have any idea's please let me know. THANKS.

A4 TDI (B6) 1.9 WITH AWX ENGINE. 2001.

 

[vw754]

been told maybe timing's out (cambelt done 9 months ago) cut a long story short my fuel gauge was not working then,it is now working,i solved the gauge problem and have a working fuel gauge for the last 2 months.

So i decided/noticed car was heavy on fuel and renewed maf sensor and coolant sensor and had the car scaned and there are no faults logged.
the guy who did the cambelt did not use a tools to lock the cam/pulleys, instead he marked all the pullys with the usual "TIPEX" and then took the old belt and tensioner off,and the new one went back on,he then rotated the engine by hand twice made sure the marks/tipex lined up and put it back together.

Now ive been told cause he didn't use locking tools,timing may be out very slightly,is this possible? ive still got plenty of power,car drives spot on,black smoke upon reving hard is present but nothing out of the ordinary. THE ONLY PROBLEM WITH THE CAR IS FUEL CONSUMPTION!
it only does 100 miles on 17.41 litres local town driving around 26 mpg.
if timing was out i would of said: starting problems,excessive smoke,and not running or performing properly,not just bad mpg!! any suggestions?

is it worth me paying again to strip the car again to find out if timing's out?

 

[46TheDoctor]

Its a difficult one really, its strange that the only symptom is bad consumption, however you aint gonna settle until you know that the timing is **** on, unless you find another reason before hand. As far as your dis range reading is concerned this figure is calculated based upon the previous tanks used, so yours will be low due to the low range it has due to its thirstiness. Mine generally reads between 550-600 upon filling up.

 

[vw754]

mine full to the brim reads 460,its good on fuel on a run! local it drinks!

 

[vw754]

if timing wasn't rite,wudn't power be down ie car would be slow,and also if timing wasn't rite wud it do good on fuel on a run? i would of thort it would be heavy on fuel both local and motorway driving.

 

[WHITEY_1]

Im not being a **** but have you checked for leaking or weeping fuel lines also check this out because you might find something out on there which is useful.

http://www.carbibles.com/fuel_engine_bible.html

 

[vw754]

checked around engine bay and nothing,also checked on the floor,nothing.

 

[WHITEY_1]

It sounds a bit like it could be the air mixture also?
Try checking the petrol/diesel cap to see if it is closing properly?
What I would do now before you park it up for the night take it for a spin for a few miles, park it up, put some newspaper underneath the engine area leave it over night and in the morning check if you have got any feul leak, Just to be 100%, if you havent then id think about getting the diagnostics checked on it! That will clear up if it is a air and fuel mixture problem,

 

[vw754]

no leaks,diagnostics=no fault codes found!

 

[WHITEY_1]

sorry vw754 i for got about your 1st post on the diagnostics

 

[vw754]

Timing is bang on! done 180 miles on 20 quid on a run (motorway) only thing i have'nt changed is fuel temp sensor...What do you guys think? ...worth changing?

Oh and the fuel cap is closing properly.

 

[Garfie]

Did you ever get to the bottom of this?

My 130 TDi FWD is only doing 43mpg and thats with taking it easy. I have a friend with a similar car and he gets 50-60mpg easily from his with only taking it easy some of the time.

I have changed the MAF sensor which made a difference to performance but not fuel economy and have also changed the temp sensor which didnt make any difference.

No fault codes logged and only occasional starting issues where it cranks a few times before starting but nothing to the point of where it's struggling to start.