Hi i had my car mapped today by ecu evolutions but for some reason the car feels under powered, The chap found a few things with the vag com they were, The specified boost was 2200 and the actual was about 1900-2000, and the maf reading was very slightly low. i know this is a problem with my car and not the map but just wondered if anyone else had this problem cheers..

The question is why would someone remap the car with known faults? If its not making boost this needs to be diagnosed, could be down to quite a few things though.

thats the problem it came up with no faults and drove fine before the map just didnt seem very agressive after the map

It says in your sig custom code map, why did you change?

Funny enough i had mine re-mapped by those and ever since i have loads of problems with boosting then no boost its costing me alot to try and find different things with the car think i am going to ask them to check to software uploaded to my car and see if that is breaking or something because it is starting to do my nut in now.

hi martin sorry about that thats my old vrs that i sold to a guy who runs the top gear saftey team, i have tried cleaning the throttle body today and checking varous boost pipes but am starting to think its maybe the n75 valve?

hi martin sorry about that thats my old vrs that i sold to a guy who runs the top gear saftey team, i have tried cleaning the throttle body today and checking varous boost pipes but am starting to think its maybe the n75 valve?

Ahh ok. Where abouts are you? there maybe someone willing to lend their n75 for a test to save you forking out for a new one.

I personally have two valves the one i use is very old but holds boost much better, the newer one is not as good.

Had the same thing with mine- actual boost wasn't getting anywhere near spec boost. Had a remap- no increase in power. Had the N75 changed under Skoda warranty after a lot of fuss, and the car was totally transformed! Give it a go.

Also worth checking that the two hoses on the N75 are around the correct way. Robert Bamford Skoda in Gloucester actually changed mine around to 'make it smoother'. This made the car 'smoother' but caused a major power loss and goosed the N75. Muppets! No fault codes and took over two years to get sorted (Bamford's wouldn't touch it because of the lack of fault code!). Winner in Cinderford sorted it in the end.

Where do you live? Maybe worth nabbing one off a mate to try.

EDIT- *Martin beat me to it*

If the specified is higher than the actual then you most likely have a boost leak, you need to check blocks 115 and 118 in Vag Com to see what the N75 is doing when the boost is requested. If it is at 100% and you are still not making the specified then its a bost leak. most likely places are the pancake pipe joint and the stupid O-ring on the other end. There is a revised pipe with a better design but I modded mine (see thread: http://briskoda.net/octavia-i/4x4-1-8t-power-loss-intercooler-pipe/142627/ )

You say the car feels underpowered but compared to what? with boost at 1900Mbar you should still be getting a good kick in the pants compared to standard..

The unfortunate side effect of any remap is theat extra stresses and strains are put on the engine and the 1.8T has lots of pipes and valves that can cause problems.. Since I had mine remapped I have changed some bits and repaired others, my boost leak is cured but I still have a small Vac leak. I am getting the car reflashed tommorrow to get rid of a problem with surging, changing the N75F to a N75J has improved it but not cured it and Chris at ECU Evolution has been really helpful in working to sort it out (he has a Skoda himself so he knows how tempermental they can be)

hi cheers for all your replies and suggestions Andy i live in gloucester so not far from you at all really how can i tell if the pipes are the correct way around? karlbar2k i am comparing it to my previous vrs with a custom code remap and chris at evolutions octy and it just feels a bit flat for some reason. i had a new turbo fitted a while ago and the garage didnt do the 3 bolts up tight on it and it was blowing pretty bad for about 100 miles back from manchester do you think this mat have damaged anything?

might have caused fueling problems due to O2 sensors not getting proper readings? I'm sure Lummox will be able to give a better answer.

does that boost reading include natural air pressure though? if it does then its only making .9bar(13psi) boost and it won't be making massive power with that boost but if it doesn't then somehow the turbo is making 27.5psi and should be making crazy power for a K03s.

that reading will be including atmos if it was done with Vag Com. I think the stage 1 map from ECU evolution should be running at 15PSI, which is the requested but its leaking

I think 27 psi would cook the turbo? I know some of the vwvortex crowd are at 24-25 PSI but big front mount coolers with water spray etc

fmic's and water injection have nothing to with a turbo's ability to flow air.

and i agree that 27 would explode a K03s.

I know that but the temps at that sort of PSI rise quickly

only on that turbo though really as surely that depends on spec of the turbo :P

i thought that turbo wouldn't even flow that much let alone compress it, years ago when i first got my octavia i called owen developements in oxford(much renowned builders of engines/turbo's for motorsports like rally etc) and they told me then that the K03s as fitted to the VAG 1.8T could only ever make in the region of 210bhp without destroying itself eventually simply down to its size and design

that reading will be including atmos if it was done with Vag Com. I think the stage 1 map from ECU evolution should be running at 15PSI, which is the requested but its leaking

His car is requesting 17.2 psi (2200mbar minus 1013 mbar) which i only get with a spike. I don't know why but the ecu is requesting more boost unless the map has been modified since mine :eek:.

Andy i live in gloucester so not far from you at all really how can i tell if the pipes are the correct way around?

Mate, you're welcome to pop down sometime and try my N75. Let me know. Will only take a couple of mins to swap over

that reading will be including atmos if it was done with Vag Com. I think the stage 1 map from ECU evolution should be running at 15PSI, which is the requested but its leaking

yeah 2200mbar includes atmos pressure so ecu is requesting 1.1-1.2 bar which is normal for a vrs. if its requesting that it should make that!

also maf reading should be around 172-175 g/s sometimes a little higher. anything lower will under powered. could just need a little cleaning!

martin what was your maf reading with this map on it?

Edited 12 April, 200917 yr by chrisjackson

try unplug your maf and see if you notice any difference

yeah 2200mbar includes atmos pressure so ecu is requesting 1.1-1.2 bar which is normal for a vrs. if its requesting that it should make that!

also maf reading should be around 172-175 g/s sometimes a little higher. anything lower will under powered. could just need a little cleaning!

martin what was your maf reading with this map on it?

I get 182 g/s Chris.

I get 182 g/s Chris.

165 was the reading on his which is considerably lower than yours. it did peak to 170 once

I suppose it depends on what mods he has, for example a high flow cat and system would push the air flow through better. Also a dirty Maf/ clogged air filter wouldn't help.

I suppose it depends on what mods he has, for example a high flow cat and system would push the air flow through better. Also a dirty Maf/ clogged air filter wouldn't help.

maf has been unplugged and car drives better which points to maf

however another maf which is believed to be good has been tried and made no difference