Poor fuel from GT TDI (BKD)

[AjayB]

My Golf GT TDI is really poop on fuel :( (or is it just me) but on half a tank of fuel (£30) i dont even seen 200 miles and this is me trying to be really careful. Somtimes when the engine is cold and im driving the trip says around 49mpg local driving, but on most occasions it struggles to get over 35mpg around town. 2 weeks ago driving to Birmingham from Bradford around 120 miles there and 120 back used half a tank, and the other half only got me a further 150miles around town(cost me 77£ to fill her up)! Its a 2004 BKD engine code 140 remapped to around 180 by Awesome GTI.

Is it just mine? or do all the rest get the same sort of figures?

[GTsport]

Sounds like you have some sort of issue some where.

My guess would MAF sensor

I usually get 500 - 600 miles out of a tank. 45 mpg + each tank full.  Best to get it scanned by vag com if you can to see if its throwing up any fault codes.

Whats it running like?

[AjayB]

It seems to be running fine to be honest. Just has a crappy start when warm but i have been told not to worry about that by Awesome GTI! It's really annoying me as i'm always at the pumps. Ive spent close to 200 in the last month on diesel! Not something i want to carry on doing! Would the Faulty MAF come up on a VCDS scan?  Is yours also a BKD?

[vRS_Pagey]

That's not good mate, mixed driving will always give more than 500 from a tank in swmbo's PD140 and its mapped so not driving Miss Daisy.

[AjayB]

Forgot to mention the car got scanned by Darren (Morty) a few weeks ago and nothing unusual came up apart from something to do with my electrics which he sorted for me!

[Matto]

My mate has a GT140 with the same hot start issues (not sure about fuel economy issues though). I scanned his and was getting glow plug faults on cylinder 1 and 3 and also a fault which related to the coolant temp sensor. Don't know if this could be linked with fuelling and hot start problems.

[AjayB]

Well i'm not getting any fault codes at all, i don't know what it could be :( really bugging me now as its just costing me too much to run!

[AjayB]

Could cleaning the EGR sort it?

[GTsport]

It seems to be running fine to be honest. Just has a crappy start when warm but i have been told not to worry about that by Awesome GTI! It's really annoying me as i'm always at the pumps. Ive spent close to 200 in the last month on diesel! Not something i want to carry on doing! Would the Faulty MAF come up on a VCDS scan?  Is yours also a BKD?

Yeah mines a BKD.  Hopefully someone more clued up than me will come along but i just know that quite a few people have had issues with the MAF sensor which has made the fuel economy poor, idle rough and some times run a little rough.

Think its one of those annoying things that doesnt always show itselfs when scanned - do you know anyone who also has a BKD that might let you swap the MAF with them just to see if it cures the rough start up?

 

[AjayB]

unfortunately i don't know anyone else with the same car/engine! Awesome told me it could be anything and told me not to mess with something that isn't bringing any fault codes up   Only had the car a few months and im trying to iron out all the problems with it so i can enjoy having the car for a few years without much problems!

Does anyone know if cleaning the EGR will have much of an affect?

[dodds-gttdi]

Get in contact with W80ody on here as he had a similar problem. He had an aftermarket intake on (K&N) I think and had a lumpy tick-over and poor mpg. He solved this looking at the EGR. Possibly cleaned it out and put in a gasket. I'll let him fill you in on all the details.

[four!]

Its worth giving it a clean. when you do though try to avoid getting too much cleaner in the electrics on the anti shudder flap part (motorised flap)

You can activate the egr using vcds and monitor what's going on.

Mine is sometimes worse than others, at the moment it has been around 40-44 around town and can normally get just into the 50's on a motorway cruise.

Sometimes disconnecting the battery for long enough to allow everything to re set itself can help.

[AdeMcG]

My mate has a GT140 with the same hot start issues (not sure about fuel economy issues though). I scanned his and was getting glow plug faults on cylinder 1 and 3 and also a fault which related to the coolant temp sensor. Don't know if this could be linked with fuelling and hot start problems.

Before I had all my injectors replaced I had a breakdown (Wire loom from ECU to Air meter) £350 and my starting was a little lethargic...nothing you would say is bad, but nothing that when you turned the key you went....oooo power...know what I mean?

Anyhoo, since the injectors were changed, the MPG has gone from strugling with 47-49 to getting over 60 easily....could you be suffering from the ECU / Air metering unit wire fault ?
Just a drunken thought 

[AjayB]

I'll try find out, the injectors seem to be all fine, the test through vcds showed that they were all working within the correct parameters. Hopefully I find the fault. Is there a way to find out easily if it's the air metering unit wire fault? Don't want to spend loads of cash :( I'd be loving to get 60mpg.

[AdeMcG]

I'll try find out, the injectors seem to be all fine, the test through vcds showed that they were all working within the correct parameters. Hopefully I find the fault. Is there a way to find out easily if it's the air metering unit wire fault? Don't want to spend loads of cash :( I'd be loving to get 60mpg.

I think they carried out an impedance check after the engine management light came on and found it to be wrong?
but wtfdik !
I am no mechanic