Help Mk5 GTi Underpowered

Chat about your MKV (6N2) Polo GTi
tegwin
Gold Member
Posts: 945
Joined: Mon Nov 13, 2006 5:14 pm
Location: Malvern, Worcestershire

Post by tegwin »

If the ECU has gone into limp mode and is deffinately not sending a signal to the solonoid I would imageine that getting the ECU chipped would possibly resolve the issue...unless there is a physical break somewhere between the EMC and the solonoid....
andyg
Silver Member
Posts: 431
Joined: Sat Jul 17, 2004 8:58 pm
Location: UK

Post by andyg »

I was considering getting my ECU remapped to solve that issue. In my situation the ECU throws up errors for cam speed sensor and position sensor even after I replaced those sensors. So perhaps the chip wouldn't overcome that?

Where is the MAF located?

Does anyone here know what other things apart from the VVT are "switched off" when the ECU is in "limp mode"?
tegwin
Gold Member
Posts: 945
Joined: Mon Nov 13, 2006 5:14 pm
Location: Malvern, Worcestershire

Post by tegwin »

Im fairly sure that in limp mode the entire engine map changes...

because the car is fly by wire, the car changes how the throttle valve moves etc depending on what mode the engine is running in...


If replacing all the faulty parts doesnt solve the issue and you are still getting ECU error codes I would be looking at the wiring loom going into the ECU, and the actual ECU unit itself..

Have you cleaned out the leaves and crap from around the ECU...its possible for it to overheat if you dont do it occasionally.!!!


If I was in your shoes I would start saving.....then find a decent auto electrician to have a look at it....perhaps try a different ECU see if that solves the issues...
N3_OLP
New
Posts: 48
Joined: Sat Nov 17, 2007 4:45 pm
Location: Somerset

Post by N3_OLP »

This looks like its going to be a little bit expensive,lol, can already feel my wallet gettin lighter...
Will take the car to the garage on friday, get her on the rollers she what she is putting out and see if the garage have any other ideas. Thanks every 4 your help, will keep you posted..
Cheers

Luke
User avatar
alexperkins
Site Admin
Posts: 14873
Joined: Sat Nov 11, 2006 5:29 pm
Drives: 91 Golf GTI, 01 TT 225, 54 T5 174
Location: Poole, Dorset, UK.
Contact:

Re: Help Mk5 GTi Underpowered

Post by alexperkins »

Did you ever get this fixed Luke?
dantheram
Gold Member
Posts: 505
Joined: Mon Oct 22, 2007 8:18 pm

Re: Help Mk5 GTi Underpowered

Post by dantheram »

I reckon mine may be like this, but as i have never know any ifferent im not sure.

it feels like its holding back until i reach 3500 4500 rpm is this normal?

Its not holding back to the extent that you think you're nver going to get anywhere but it feels like something changes at higher revs.

Dan
User avatar
Bradley
Gold Member
Posts: 974
Joined: Thu Jul 16, 2009 5:51 pm
Location: Kent

Re: Help Mk5 GTi Underpowered

Post by Bradley »

dantheram wrote:I reckon mine may be like this, but as i have never know any ifferent im not sure.

it feels like its holding back until i reach 3500 4500 rpm is this normal?

Its not holding back to the extent that you think you're nver going to get anywhere but it feels like something changes at higher revs.

Dan
Thats quite normal mate,it's to do with the addition of another cam operating at higher rev's.When the oil temperature & pressure reaches a certain point in both catergories the twin cam kicks in giving the engine more air making it increse in acceleration quite abit.You'll notice a slight change in engine sound around 5,800 rpm if i remember correctly where the VVT comes in too.
dantheram
Gold Member
Posts: 505
Joined: Mon Oct 22, 2007 8:18 pm

Re: Help Mk5 GTi Underpowered

Post by dantheram »

Bradley wrote:
dantheram wrote:I reckon mine may be like this, but as i have never know any ifferent im not sure.

it feels like its holding back until i reach 3500 4500 rpm is this normal?

Its not holding back to the extent that you think you're nver going to get anywhere but it feels like something changes at higher revs.

Dan
Thats quite normal mate,it's to do with the addition of another cam operating at higher rev's.When the oil temperature & pressure reaches a certain point in both catergories the twin cam kicks in giving the engine more air making it increse in acceleration quite abit.You'll notice a slight change in engine sound around 5,800 rpm if i remember correctly where the VVT comes in too.
it's not often i push her that hard but i'll lisen out. Good to know all is normal tho, i plan on cleaning the throttle body this weekend so it should be perfect then

:lol:
User avatar
Bradley
Gold Member
Posts: 974
Joined: Thu Jul 16, 2009 5:51 pm
Location: Kent

Re: Help Mk5 GTi Underpowered

Post by Bradley »

Nor me but when i get the chance on a quiet dual carrage way it's nice to see how it can run haha.I would,i use Wynns carb+fule injection cleaner it's reallly good stuff and removes all the crap quite easily.Hope you sort it out alright.
6n2si
Getting There!
Posts: 80
Joined: Tue Feb 10, 2009 4:45 pm

Re: Help Mk5 GTi Underpowered

Post by 6n2si »

Its not actually another cam lobe like in Hondas VTEC system. The VW systems works by changing the cam timing using a hydraulically actuated tensioner. Regards to your car, I would never describe my car as sluggish low down, and its totally standard so I would definently get it looked at by a VW specialist 8) cheers.
User avatar
Bradley
Gold Member
Posts: 974
Joined: Thu Jul 16, 2009 5:51 pm
Location: Kent

Re: Help Mk5 GTi Underpowered

Post by Bradley »

6n2si wrote:Its not actually another cam lobe like in Hondas VTEC system. The VW systems works by changing the cam timing using a hydraulically actuated tensioner. Regards to your car, I would never describe my car as sluggish low down, and its totally standard so I would definently get it looked at by a VW specialist 8) cheers.
I didn't mean like Honda's VTEC which you're right that does actually change cam profile by swapping over to different lobes.I meant by being twin cam things are sped up quite alot i.e. more air allowed in and more air forced out at higher revs due to an increase valve timing.
Post Reply