Just had my car on a rolling road this morning and didnt get the figures i was hoping for. I got 180bhp and 220lb/ft torque from a stage 1 map.

The garage carrying out the rolling road test stated that i could have a dodgy recirculating valve? Does this sound possible? I have a compbrake one fitted just now but surely that can't be the issue. I have a standard dv at home so iam going to swap them over just to be sure.

Its so frustrateing as the car does feel down on power it was feeling fine before then i had split pipes and now this other issue.

Bloody cars lol.

Which spring did you fit in the comp brake valve? It comes with 2

I put the stiffer of the springs in, i also then tryed the yellow spring from forge when i had surgeing issues. I am hoping on the off chance that my dv is knackered would save alot of hassle.

Seems like you have had nothing but issues Paul!!!! What was the boost doing on the rollers??

More the likely is the dv have seen this with fooked dv30 out of the box so it can happen!!

More the likely is the dv have seen this with fooked dv30 out of the box so it can happen!!

I know maybe my car just dosn't want to be mapped lol, i haven't got the print out to hand so can't check what boost its produceing. It feels quick though in the high revs. So a dodgy dv is not uncommon then? Hopefully it is i won't be able to try untill sunday.

So you switched map from Shark to Revo, and still have problems?

Might indicate that it was a hardware problem all along. Did the RR guys plot the boost for you, or do you have a boost gauge?

You already switched from a diaphragm to a piston DV, so your DV should be pretty reliable now. Maybe you just have a leak somewhere.

Yeah that's correct bodge i swapped from the shark to revo. The revo map was fine to start off with felt really good this issue has only started a couple of weeks ago. No they didn't plot the boost unfortunately and i don't have a boost gauge which dosn't help i know.

I have uploaded a couple of pics of my printout from the rolling road session

I know the pics aren't great and tbh i don't know much about turbo'ed cars and figures etc but anyone with a bit more knowledge might be able to have an opinion on it. This is the only printout i received from the rolling road guys.

I am away on holiday just now but managed to have a wee poke around the engine bay and i have found another small split on a pipe under the manifold and i mean very small but it is split. I wonder if this is another factor why the figures are so low? i will be replacing the pipe anyway when i get home.

I have managed to get a couple of screwdrivers this morning so i can whip my dv out to check.

What is the test that can be carryed out to check if the dv is faulty? Is it when you push the piston in it should retract on its own? Any help would be great

Cheers

I have managed to get a couple of screwdrivers this morning so i can whip my dv out to check.

What is the test that can be carryed out to check if the dv is faulty? Is it when you push the piston in it should retract on its own? Any help would be great

Cheers

Yep, the piston should push back and make a seal.

The checks that I would do are;

Push the piston up then seal the vacuum pipe (one on the top of the DV), release the piston and it should stay in place, if not, it’s leaking somewhere.

Try blowing into the side port (feeding back to the turbo pipe). If you feel resistance, then the piston is doing its job. If there are any leaks/hissing, you could be loosing boost.

Well fixed the split pipe tonight (still hoping to eventually fit a oil catch can) and the car drives a good bit better now still not 100% though. I tried unplugging the MAF and taking it for a drive but it felt the same.

I was thinking though tonight could my n75 maybe be faulty just with age? the car is 9 year old now. I was reading up on these different "performance" types of valves that you can get they seem to have a varied opinion though would it be worth trying one of them?

The company that remapped the car are willing to take it back though and check the settings of the map to make sure its running properly. I am hoping its a case of tweaking the map now to suit the car.

I also scanned the car tonight with my ebay code reader and no faults were showing.

Would it be worth just getting a cheap boost gauge, run it from just under the bonnet through the window and see what figures you get?

Would it be worth looking at simple things like the panel filter, coilpacks, sparks?

Yeah i was thinking about a boost gauge next just to see what its produceing. I wouldn't ave to wire it up though would i just plumb it up to a boost hose?

Coilpacks were done under the recall, plugs were just done at recent serive. I am going to get the garage to do a smoke test to double check i haven't missed anything.

I've got a gauge n vent pod that I'll sell ya

Could be interested si,

How much?

i think the best option is to take it back to mapper and get them to scan the car and maybe road test to do some logs!!!

maybe the issue has been mechanical all along with your car paul???

another issue it might be is a weak actuator but you will see this with a boost log if its not making requested boost!! ( must ensure you have no boost leaks first)

wouldnt be the first k03s with a weak actuator ive seen thats for sure!!!

I don't thinks it been a mechanical issue all along, the revo map was working fine this issue has just become apparent. Maybe it has always been here like you say mate and its just becoming more noticeable i reall don't know.

Its hard up here as there are no rolling roads or garages that really specify in remaping/tuning cars. There is defenetly an inprovemnet now though with the new pipes. The car is going in on friday with the mapper to see what he thinks. He guarentees me its not a map issue? But i have told him to carry out boost logs etc and see if the car is making the correct boost.

I started having thoughts that maybe my turbo is possibally failing i don't know though could really do with a tuning firm up with me who have a rolling road to see what my car is doing.

get the boost logs done and if its not getting to requested boost level try bending the actuator arm very slightly as it might be a weak actuator and thus bending it slightly will help that!!!

Right good news my car seems to be fine again , The car had gone into safe limp mode because of the split pipe it seems to be going well now.

Just thought i would carry out some tests on my DV anyway, Am i correct in saying that when the piston is pushed up and the top small opening sealed the piston should remain in the same place? My valve dosn't seem to do this when i try it which is making me think that it could be faulty.