Hello,

My car's been absolutely solid, until failing its MOT on emissions a week ago. Failed on lambda. No CEL on the dash though. I've had a lambda warning in the past, however, so changed the front lambda over the weekend. Nightmare of a job, but done. Car started fine, seemed smooth, then went a bit lumpy, then gave three beeps in the cabin with the temperature light on the dash.  Coolant was below minimum, car was jacked up about a foot at the front, so got it back on the ground, coolant still low, so topped up. I never let the coolant get low, so I'm not entirely sure where it's gone because I lost almost none during the lambda change. The car doesn't want to start now. The 3 beeps and the temp light occur while the car is just on ignition about 30 seconds after turning the key. Currently I've no error codes having cleared them after doing the sensor. The sensor itself is the OEM Bosch one from eurocarparts, same as the one that I removed.  All my connectors are in (I don't think the car would have started in the first place without that being the case) all the hoses are connected, but something's amiss. 

Anyone got a clue what the ignition - pause - 3 beeps temp light is indicating on a cold, level, topped-up, ignition only (not running) engine means?

Thanks

Nathan.

Leaving the battery off over-night to see if my problems are to do with the ecu remembering how to run with the old lambda sensor. 

Nothing to do with the new lambda, or the ecu. Still wouldn't start. Turns out I've done something wrong w.r.t. piping up the throttle body. The result? Throttle body full of coolant. manifold full of coolant. Cylinders full of coolant. Water doesn't ignite quite so well as petrol! So after it started and idled nicely, it then sucked coolant in from somewhere (my piping error), went lumpy after 20-30 seconds, then the alarm beeps went off in the cabin with the temperature light on. That warning came on because the coolant had been drawn out of the reservoir by whatever I'd done wrong. Then it stalled. And wouldn't start, obviously.

 

So the plugs are out and dried. Throttle body dried. Manifold dried. Engine cranked over to blast the coolant out of the cylinders, and it's ready to go back together. Only this time I need to get the piping correct.

I had to laugh. I now owe this car a new lease of life, and I'm going to have it back on the road. 40k miles to go to get it to 200k. Then I'll be happy.

The moral? Haynes doesn't have good enough pictures, and what I should have done is taken a photo of what pipes were where on the throttle body. Instead I thought the pipe shapes and lengths would determine where they naturally sit, but obviously not.

Hi Urban, if the cylinders had coolant in them I'd strongly recommend a full oil-change and new filter - coolant will almost certainly have got into the sump. 

A response! At last! That's a very good shout, thank you for that. I have a spare filter and can of oil in the garage too. And by extension, it might even need a flush of oil after a running for a short while. I've no intention of failing to get it running, presently. And I'll be gutted if I fail. It was only a £700 car, but in great order, and this is no way to kill it.

To wrap this little saga up, the Skoda....lives! And I'm well happy about that. What did I learn? As I put it together the first time round (when I did it wrong) I did mentally note 'How weird that the throttle body connects to the expansion tank. What's that all about?' But without knowing any better, I pressed on, after all the pipe seemed to 'land' in the right place, so that's where it must connect. It's only now that I realise what that particular connection is for, and that the throttle body is basically always in a state of vacuum, that I see what went wrong. The vacuum that would normally draw vapour from the charcoal canister instead, piped up to the expansion tank, drew the air out of the tank, which caused the coolant to follow it out of the block and into the tank, and once there was no air left in the tank because it was full of coolant, the coolant then got dragged into the throttle body, then filled the manifold, then hit the cylinders, then got exhaled into the exhaust pipe work before the car didn't want to run anymore. 

 

Getting the coolant properly out of the cylinders took a while, but once put back together correctly, with oil and filter changed (it turned out to be the case that there was plenty coolant in the sump) and with the plugs cleaned off (only got about 40 miles on them) the car fired right up like nothing had happened! Not a cough, not a splutter, it just ran. Then the steam started coming off the block as the coolant evaporated, and when I went out for a drive it looked like I'd Seafoamed the intake as the coolant got evaporated out of the exhaust pipe work. 

 

Had to do a throttle body adaptation, then ran the car through the full vagcom readyness check and it's all looking good. This all came about because it failed the MOT based on emission because the lambda reading was wrong, so I really do hope it passed now.

In the meantime here are a couple of videos that show what a complete balls-up I made of the lambda change job. By the time I'd realised how much coolant was in the manifold I'd already poured half of it out, but there was plenty still to record.