************* Update 7-5-11 I have updated the title to this thread after now having input from Shark Performance, It would appear to be an issue with some mk1 vRS Octavia's running a particular software from the factory. If you are suffering surging issues and your car was working fine before it was remaped (by any tuner) please update any advice or solutions, thank you8*******************

does it only do it when cold? showing any fault codes? the 1.8t's are very prone to the stutter when on the cold start with the secondary air pump running, and any slight boost leak will cause fluctuating boost,

does it only do it when cold? showing any fault codes? the 1.8t's are very prone to the stutter when on the cold start with the secondary air pump running, and any slight boost leak will cause fluctuating boost,

No fault codes and no it does it all the time. I do not take it above 3.5 rpm when cold anyway but its there all the time. I did consider the removal of the SAI but not seen this as a direct cure for surging in this manner. I have done quite a bit of digging through the forum archieves but nothing that jumps out other than the usual cures.

I know I might be stating the obvious but you are running it on high octane?

I had a similar problem with my 48k mk1 vrs with a custom code stage one remap... Little did I know that my tightfistedness by buying standard unleaded was the cause.

Hope I am not stating the obvious.

Tim

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Hi Tim thanks for the post, it is alreay mentioned though mate. I always run it on super unleaded. Only from BP or Shell. Drives my misses mad

Oops didn't see that. Good luck with the hunt for a cure.

My wifey hates the need for super as well!!!

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Hi ollie

Iam also running a shark stage 1 remap and experiencing exactly the same problem boost will surge quite bad in 3rd 4th and 5th gear. I have tryed swaping n75 valves with one off my mates golf gti but didn't do a thing. I also checked for split pipes couldn't spot any. I have been told changing my spark plugs could solve this but you could spend hundreds of pounds trying to solve it and not get anywhere. Its very annoying.

Do you have a boost gauge? What does it say? Does the boost suddenly drop when the engine hits high revs? Light misfiring at high boost is usually associated with spark plugs (not gaped right) or bad/failing coils. Definitely you should replace the spark plugs, in vwortex FAQ they recommend NGK BKR7E with spark gap 0.7mm and also according to replies in my thread they are the best. http://briskoda.net/forums/topic/194858-spark-plugs-vrs/

I don't have a boost gauge fitted maybe ollie does though?

Yes the boost kicks in then off then on then at 5k it will pull smooth. It seems like me and ollie are experiencing exactly the same issue though.

Sorry ollie for hikacking your post seems we have the exact same problem.

I had this and the only thing that cured it was a different map from a different tuner. For some reason, Paul at RS Tuning smoothed everything out and since then, the car's been great. Probably not much help, but it worked for me.

what about removing the n249. Failing that get it on a rolling road so it can accurately be logged to see whats going on. I'd recommend R tech, their reputation is very good.

Try bypassing the N249. This cured my random on/off surging... My link see post 17 for the pipework layout...make sure you use a brass t piece though as the plastic one I had broke after less than 100 miles.

EDIT beat me to it Mike!

Edited 15 March, 201115 yr by tarmacsurfer

what about removing the n249. Failing that get it on a rolling road so it can accurately be logged to see whats going on. I'd recommend R tech, their reputation is very good.

You phrased it much better than me. It was the rolling road and ability to log everything that cured my issues. In no way was the previous map duff, it just didn't suit my car. The extra for the rolling road really was worth the money, as I didn't have to buy any new parts.

I had this and the only thing that cured it was a different map from a different tuner. For some reason, Paul at RS Tuning smoothed everything out and since then, the car's been great. Probably not much help, but it worked for me.

I had exactly the same - boost surging all the way through the revs.

Had the map looked at by another tuner who advised me that the map was running too much boost. He did a new map and backed it off a little bit and the car feels much better and is faster.

Edited 15 March, 201115 yr by urbanfox

I really don't want to throw anymore money at it trying to solve this its really starting to get annoying. I think this map just dusn't agree with my car if it makes sense. I know shark have a great reputation and there maps are great but i just think this map hasn't agreed with my ecu possibally. I had a revo trial map and i din't suffer from any surges. Its a very frustrateing subject :-(

I just thought it might be worth popping my head in here. We've only experienced this problem three times and have done scores of Octavia VRSs, even tested two cars back to back with exactly the same software.

We are working with Ollie to get this sorted however it is proving hard to find a time when we are both available to look at it for a length of time.

Once we have sorted it on that car we may have a better idea on what to tell other customers (PaulMoVRS namely) and if we come across the same problem in the future.

Take out the k&n and change the MAF again the oil from the K&N is fouling the MAF I had the same problem

Please post back the solution of the problem, this could help a lot of people.

k&n won't be the issue. First thing I'd try is a N249 bypass, it costs nothing and if it doesn't work you can put it back easily.

As mentioned also, what plugs are you running, when were they last changed, coilpacks? Also any fault codes.

I have no fault codes showing when the car is scanned. Plugs were the next on my list to change as i don't know when they were last changed.

Mines running a shark map and has been fine although as others have mentioned I've removed the sai, n249 etc and got rid of most of the pipework that could be causing you guys issues.

Wow a lot of posts to look through there.....

The main aim of this post was to make sure I have not over looked anything before I take the car back. I have already thrown £150 at this issue on the usual problems, although I would have bought the new hoses anyway.

I am not convinced its the map as Ben has already tried backing it off and is working very hard with me to solve the issue

I changed all the coil packs 4k miles ago. One failed so I changed them all. At the same time I replaced all the spark plugs with Bosch items, not sure the exact plug. I ordered the ones listed for the car on euro car parts. I did all this before deciding to have the map as I wanted the car to be in tip top condition.

The only other thing that was at fault with the car was a coolant leak but I had this resolved between the first and second visit to shark. The waster pump was causing the problem.

I do not have a boost gauge fitted unfortunately.

If the plugs were to blame would the problem not have been there before the map?

I don't really want to start removing valves pipework etc just for selling on purposes. My next move is to change the plugs but i wnt be spending anymore money after that.

Would you mind ollie leting me know when/if you solve the problem.

get ben to remove the map then if its gone you know its a problem with the map and doesnt matter how many things you change it wont cure it!!!!