Hi,

I have a 2004 Octavia drive 1.6. (European Version) Engine code BFQ. 102 BHP. Converted to run on LPG. It's done 212000 km

Over the last few weeks, it's starting playing up when starting. It would splutter into life and then cut out. Second start would be OK. Then it would have erratic idling. also have flat spots.

Took it to my Garage (they have VAS) and it not showing up anything new. (the orange engine light has been on for a while and is showing a problem with the lambda after the catalytic converter. Standard problem I'm told after LPG conversion)

Mechanic cleaned the MAF, which helped with the erratic idling for a while. Went back next day and he clean the throttle body. That then helped with flat spots and starting.

He was a little concerned about fuel pressure but not overly.

It's had new spark plugs and HT leads.

Could it be the coolant temp sensor, even though their is no fault code?

BR

Chris

Could be the coolant temp sensor, the code you will get for that is (I think) 17704 but if it's only just started going it might not have got bad enough to make the code come up.

Is the coolant gauge ok? Does it ever read like its overheating or stick on 90 all the time when it should warm up slowly and then stick at 90?

Hi,

It warms up OK and sticks bang on 90. It did start to overheat two weeks ago on a Sunday, but I put that down to outside temp being 37 degrees (in shade and being stuck in traffic for two hours). Found out that larger of two ventilator fans is broken and needs replacing. Not normally an issue when driving, but just in those extreme conditions.

BR

Chris

It's worth changing the CTS as it is notorious for failing. CTS has 2 feeds. i.e. One for the gauge & the other to the ECU. Often when the CTS is failing it can cause the gauge to act oddly, however it is common for the gauge to appear normal. but the ECU is getting wrong info from the CTS.

If you have climate control you can use it to access a load of stuff including what the temp sensor is telling the ECU. Just a few weeks ago a friend of mine's Polo started to idle at 1200rpm when warm, the gauge read 90, but when we checked the ECU it was reading 70. Stuck a new CTS in & all was well again.

It's worth changing the CTS as it is notorious for failing. CTS has 2 feeds. i.e. One for the gauge & the other to the ECU. Often when the CTS is failing it can cause the gauge to act oddly, however it is common for the gauge to appear normal. but the ECU is getting wrong info from the CTS.

If you have climate control you can use it to access a load of stuff including what the temp sensor is telling the ECU. Just a few weeks ago a friend of mine's Polo started to idle at 1200rpm when warm, the gauge read 90, but when we checked the ECU it was reading 70. Stuck a new CTS in & all was well again.

Hi,

Thanks.

Don't have climate control, but manual A/C.

Is it an easy job to swap out?

BR

Chris

Really easy 5 min job on a 1.8T. It's located on the rad top hose, but not sure about 1.6. Sure someone on here will be able to help.

I believe the CTS is located on the bottom rad hose on 1.6. Take a look at this sounds like he had the same problem. http://www.diynot.com/forums/viewtopic.php?p=1575762

Might be worth having a look at getting a new Air Intake Temp Sensor which goes in the throttle body . That sorted my dodgy revs

Hi,

Thanks all for the help.

Paul Dazzle,

Indeed sounds very similar to my problem. and I know the lambda after the CAT is shot, but has been shot for about 18 months now. My problems only stated a couple of weeks ago, which makes me think it is something else.

VRS Nick,

Would the air intake sensor show up as a fault?

BR

Chris

You can clean the AIT with Isopropal alcohol or carb cleaner, & a cotton bud. I doubt thats the problem though. If Lambda sensor is dead I would change that asap.

Polish Skoda dealer are quoting around 193 GBP (900 Polish Zloty) for a new Lambda after the CAT. Is that steep bu UK standards?

BR

Chris

Wow! that seems very expensive. Have a look on ebay, & GSF.

Any clue of part number for the Lambda after the cat?

C

J0 857 819

new part number is 1J0 857 819 H retail around 20 quid

Lamda Sensor Bank 1 Sensor 2 (the one after the CAT on an AUQ engined car)

Skoda Part numbers 06A 906 262 Q or 06A 906 262 BB �117.84 + VAT

or the equivalent Bosch Sensor Part number 0 258 006 245 �72 + VAT

There are loads of Lambda sensors for VAG cars on ebay.