Runs rich on start up?

LeonL · July 30, 2009, 11:53:09 PM

Hi,

Just wondering what would cause the G40 to run rich on start up. Idles at above 1k revs when starting the car from cold, sometimes revs up and down a little under its own free will and then after a short time the car idles fine(im assuming once it has warmed up). I can smell petrol on start up as well, also indicating the car is running rich right? Other then this the engine runs smooth and doesnt seem to have any problems...

Any ideas?

Cheers

Leon

Dan · July 31, 2009, 08:35:56 AM

Possibly the blue temp sensor. I assume you have been through everything on the diagnostic guide.

Dan · July 31, 2009, 08:42:23 AM

Thinking about it, it could just be normal. They are a bit richer on a cold start map. Although it shouldn't smell too much of petrol.

LeonL · July 31, 2009, 08:55:44 AM

Part number for blue temp switch and were can i get a replacement?

Thanks

MartinB · July 31, 2009, 05:40:50 PM

VW Dealers. Don't accept imitations!

DKnight · August 01, 2009, 01:50:31 AM

hell dont accept vw either, i got a vag one and it was as shit as the gsf one

best bet is to scrap yard grab a load...

Dan · August 01, 2009, 11:37:54 AM

At least if you go to VW you can send it back and get another, which is more than GSF's policy on electrical parts.

LeonL · August 03, 2009, 09:52:53 PM

Part number anyone? I'll get on the case and get one asap

Also any ideas on the price?

hayesey · August 03, 2009, 09:57:20 PM

it's about a tenner, no idea of the part number just ask for a blue temp sender for a mk3 polo g40 and they'll find it no probs.

LeonL · August 04, 2009, 07:05:54 PM

Not to bad then, cheers...

I'll get onto it at the weekend

Problem after problem these g40's are

Doc J · August 04, 2009, 08:06:12 PM

All the blue temp. se4nsors on the MK3 Polos are the same, so... It's not necessary to say G40, just ask for MK3 Polo

But I think it's normal to run rich when it's cold. Before some time I've red a russian book for the gasoline engines and there was wrote why when the engine is cold the AFR is rich. So... I think You've got no problem.

Mine is running rich when it's cold too and I know all is OK.

hardchargin40 · August 07, 2009, 08:27:35 AM

yeah but it shouldn't be running overly rich on cold start cycle. Always best to change the blue CTS.

LeonL · August 15, 2009, 10:45:47 PM

Just a little update,

Went into VW with the blue temp part number i found in another topic(VagCat part number for 1991 G40 model), also took the part number i found on VagCat for the 1994 model G40 which was slightly different to the 1991 number.

They said the part number for the 1991 blue temp sensor didnt exist anymore but the 1994 one i supplied did.

Either way ordered the sensor and part number for anyone who needs it is: 025 906 O41A

Olly G40 · August 16, 2009, 07:39:15 PM

is it not the fact that the chokes on?! i wouldn't let it worry you mate...

bbvw · August 16, 2009, 10:13:09 PM

it will start up rich anyway every engine does that till the engine is at right temp to run smoothy at idle.