Hello to everyone, joined ages ago and just used the site to search around for info every now and again, I tried posting in ask a tech and it seems I am not allowed. My octavia vrs mk1 has just became a nightmare in the last couple of weeks, and so far changed is the MAF, both lambdas, cam position sensor, crank sensor and coolant temp sensor. though I am about to change the lambda again as the new one ended up worse than the original, no other fault codes other than the lambda. I only have the shareware version of vagcom so cant do a full scan. the main problem I am having is that the revs seem to drop very fast nearly to stall whenever i push the clutch or even at idle. If i rev the engine the needle drops faster than normal dips to around 500rpm then back, and also when driving i seem to get like a flat spot at varying rpms as if I have hit a limiter and then back to normal. any Ideas? HELP ME PLEASE :confused:

Air leak somewhere? These cars are prone to acting up with the slightest air leak...

EDIT: What the F*** is wrong with my keyboard? It keeps missing leters asi type...

tried looking everywhere for an air leak, squeezing tubes and hoses everywhere but no joy with that one. some days do seem better than others, but the problem just doesn't seem to go totally away

check the crank case breather hose , all the way down and around the front of the engine there is a green valve on the end of it , the oil vapour causes the pipes to go very soft and they crack and split , i had the same problem on my black one when i got it check it out mate i could nt hear a leak either

also if the pipes have got to the stage where they are brittle there will likely be a few others (thinner one from under the manifold that joins the crank breather one normally) as well as the pipes you may need to do a throttle body clean, well documented and very easy to do, cheap as well )

thank you will do that on the weekend now fingers crossed with that one will let you know

I'm thinking either a breather hose or possibly the idle stabilistation control or throttle potentiometer.

So check the hoses first because that's free, then, if possible try and log the data from idle stabiliation and the throttle pot.

stupid question. instead of just changing parts ad-hoc, why not take it to a dealership or independent for a check up/service? I nearly changed the MAF once convinced it had failed. Turned out to be a temp sensor. Dealer fixed it while I waited for about £30.

the parts that were changed were throwing codes, have had it diagnosed at an independant twice, all my other problems are sorted, now I am just stuck with this one. At one stage I couldnt even get it to start before I had a new cam sensor put in, as I said the past few weeks, the car has been a complete nightmare. car is booked in again for saturday when the new precat lambda is going on, I have printed out the checklist of hoses that people have told me to check and will give them to the mechanic to check for me

hopefully i will have the fun reinstalled into my car

update here had car diagnosed at main dealers, 2 hours of diagnostics and all they could tell me was the lambdas were sooty again, cleaned those, and my turbo hose was loose. Car a little better now, less hesitation idles a bit better, but milage still around 26mpg had all the wiring for the lamdas checked right back so its not them, and no air leak found. reccomendations for anywhere not too extortionate in south wales I can take it for further investigation?