Gti6 Engine Problem

[Flying205Nutter 4]

Hi, I am having a problem with the gti6 engine in my 205. It runs perfectly in every respect with the exception that is runs very lumpy on part throttle at 2000rpm (driving not static) its much worse when cold but still noticeable when hot. Its almost so bad when cold that I cant drive up an incline at 2000rpm without using full throttle.

 

Parts I have changed (all from my other vts/6's and are known good parts)

 

engine! (changed for a different reason but problem existed on the old engine)

ecu

all sensors excluding knock (changing knock now)

injectors and regulator

Lambda probe

New fuel filter

new plugs

coil packs came over with new engine, have tried the old ones with no difference.

 

The only things left are the fuel pump (although it pumps out petrol fine when pipe removed from fuel rail)

 

and changing the wiring loom.

 

For info I am running full grp N engine mounts which obviously make it more noticeable and I have removed the resonator from under the inlet. K&n cone filter, Magnex decat pipe with lambda probe (tested and working fine at MOT) and full magnex exhaust.

 

Any help would be appreciated.

[boldy205 75]

This sounds like something in the electrical/fueling on the 'car' side of things then, as you say you have changed the engine, and the problem persists?

 

Matt

[chipstick 382 1 Cars]

What did you bloke the resonator hole with?

 

Did you take the complete inlet over with fuel rail and injectors and swal or leave the one on that came with the replacement engine?

[mikeygulley 19 1 Cars]

I had a similar problem with my motor and after changing many things I finally changed the fuel pump! Which cured it. Even though the old one was pumping it wasn't doing the job properly.

 

But I haven't removed the resonator so as chipstick asks, how did you block the hole?

[Flying205Nutter 4]

Thanks for the reply's,

 

I started using the old inlet complete but have now swapped everything over bar the inlet itself, so throtle body complete and fuel rail inc injectors.

 

Resonator if blocked off properly, I cut the plug off the resonator and plated over the back of it will a small piece of stainless steel, But I take it you think an air leak in the inlet causing the problem? I will look into this.

 

Is there any way of testing a fuel pump? where is the best place to get one from?

[Flying205Nutter 4]

Fuel pump changed, no difference.... Resetting ecu again see if that makes a difference.

 

Image of reonator bung - https://www.dropbox....%2012.47.09.jpg

[kyepan 291]

does sound like an air leak, can you hear any obvious fush fush sounds when it's idling?

[Flying205Nutter 4]

does sound like an air leak, can you hear any obvious fush fush sounds when it's idling?

 

No, it all sounds and runs fine except at 2000rpm, idles as it should, pulls perfeclyt from 600 - 1800 and 2200 - 7000

[Flying205Nutter 4]

I have checked for air leaks and found none, I have driven the car with the servo pipe disconnected and that made no difference to the problem. Here is a video of it running. The microphone on the phone makes it sound really tappety.

 

https://www.dropbox.com/s/ro3jcwcwmve0kw6/2012-08-17%2014.11.29.mp4

 

If it supposed to hunt with the vacuum pipe disconnected?

[CosKev 16]

Yeah it will hunt with that pipe off,you are bypassing the idle control valve.

 

I've got exactly the same problem as you with my 306 Rallye,very similar mods too.(modified airbox,sports cat,Scorpion exhaust)

 

Hoping its not down to removing the resonator,as I had the hole welded up!!!!

[Flying205Nutter 4]

Yeah it will hunt with that pipe off,you are bypassing the idle control valve.

 

I've got exactly the same problem as you with my 306 Rallye,very similar mods too.(modified airbox,sports cat,Scorpion exhaust)

 

Hoping its not down to removing the resonator,as I had the hole welded up!!!!

 

I was expecting it to rev up to say 2000 rpm not hunt up and down.

 

I am please to find someone else with the problem as its very annoying.

 

So job for today refit my resonator. I cant see it making a difference but I have tried almost everything else.....

[Flying205Nutter 4]

Right the resonator has been on and is back off again. Made no difference. Giving up now unless someone can suggest something else? If I find a new 306/xsara loom I will swap that over and see if the problem is in the wiring.

[CosKev 16]

Right the resonator has been on and is back off again. Made no difference. Giving up now unless someone can suggest something else? If I find a new 306/xsara loom I will swap that over and see if the problem is in the wiring.

 

Glad the res did not sort it!!!

 

It is annying this prob,but mine is barely noticeable once upto normal temp.

 

But is pretty bad when cold.

[cheesegrater 43 1 Cars]

Mine does this. I put it down to something related to coldstart. Doesn't do it when its warm.

[Flying205Nutter 4]

Mine does this. I put it down to something related to coldstart. Doesn't do it when its warm.

 

I cant believe a mass produced engine should run this badly when cold? I have never had a car that does this even on carbs so with modern ecu management its should be silky smooth. Also all three of my vts's and my xsi don't do it proving its not normal.

[Spiky 37]

car should be smooth, hot or cold

 

mine was fine when it was std, with ITBs and now with Supercharger, starts and idle's perfect

 

they is something up with anyone's that doesn't

 

are you running PAS? try unplgging that

 

isc could be faulty and allowing air in?

[Toddy 7]

Have you replaced the TPS?

[CosKev 16]

My Gti6 engined 309 never did it,neither did my first 306 Rallye,so deffo something amiss somewhere.

 

Going to try unplugging various sensors one by one and see if that reveals anything

[Flying205Nutter 4]

Have you replaced the TPS?

I swapped the whole throttle body,complete. old body working fine on vts.

[Flying205Nutter 4]

My Gti6 engined 309 never did it,neither did my first 306 Rallye,so deffo something amiss somewhere.

 

Going to try unplugging various sensors one by one and see if that reveals anything

 

Hi, thanks for confirming that it should run smoothly even when cold. So that's 2 other users with the same problem! I have replaced all the sensors now and all the old sensors are running fine on my vts. Has to be wiring now so will get a new loom and when I am board convert it and fit it. God know what to do if that does not sort it.

[Flying205Nutter 4]

car should be smooth, hot or cold

 

mine was fine when it was std, with ITBs and now with Supercharger, starts and idle's perfect

 

they is something up with anyone's that doesn't

 

are you running PAS? try unplgging that

 

isc could be faulty and allowing air in?

 

No pas but I have still got the sensor pluged it. Should I unplug it?

 

isc - idle speed control? I have swapped the idle control valve if that's the same thing? Made no difference. car starts and idles perfectly, never stalls.

[Alastairh 47]

Tried swapping the cam sensor? Not what i would go for straight away, but i have a mate that had similar issues, i gave him a cam sensor off a scrap engine i had and sorted it.

 

Al

[Flying205Nutter 4]

Tried swapping the cam sensor? Not what i would go for straight away, but i have a mate that had similar issues, i gave him a cam sensor off a scrap engine i had and sorted it.

 

Al

 

I am using the cam sensor that came with the new engine and ran fine in the vts.

[Paul_13 212 1 Cars]

Same problem here, changed spark plugs, coils... Only started to do it recently though.

[Toddy 7]

Best wire in the diagnostic port, not sure whether peugeot planet shows live readings data,