Hesitation at 2700rpm & Emissions light

[rob - 73]

Could anyone give my their thoughts on this one... since I services my forge 007p (with the forge kit, so new o-ringes, piston, grease) I had been getting a hesitation at @ 2500-2700rpm just when the turbo would kick in, its like a sudden cut of power.

I have checked around the hoses for possible tears or holes, the only thing I could find was a couple of cracks at the intake hose (under the DV) but not all the way through. Also the breather hoses where covered in oil (is ths normal). Finally the Y shapped hose is very, very soft these days.

Would any of these cause this hesitation?

If so I have already priced the forge hoses and dont mind replacing them, just want to make sure thats what it is.


On a similar thing, which is more worrying last night on the way home from work my "Emission Warning Light" came on and has stayed on... would this be linked to the possible boost leak described above or is it one of the follwoing:-

Coolant temperture sensor

Coilpack

or something else??

I am taking the car to a local indepent VW/Audi garage to hook up to VAG.COM to see what we get, oh yeah it just passed its MOT last week.

Any ideas on this matter would be great, cheers guys.

 

[mikebrennan]

Hi there mate.
I get hesitation at the exact same rev range as you,but get no lights on the dash?
Seems a lot of people on here get this and changing the CTS solves the issue.haven't done mine yet though.
Please re-post if you manage to get it fixed.

 

[rob - 73]

Will do, as soon as I get the vag.com data I will have a better idea.

Would be good to hear others symptoms and thoughts??

 

[rob - 73]

Further info / update after getting VAGCOM done I got the following codes:

17544 - Fuel Trim: bank 1 (add): system to lean. P1136 - 35 -10. *Intermittent*

16486 - Mass Air Flow Sensor (G70): signal too low. P0102 - 35 - 10. *Intermittent

Was advised that the MAF needed replaced, even though I fitted a new exchange Bosch unit from Euro car parts about 18months.

So fitted another MAF from eurocarparts, Bosch unit again.

So I did that and unfortunatly the problem is still there, hesitation at 2700-3000rpm and loss of power. Emissions light is back on.

So I am now thinking it has to a boost or vac leak. As I mentioned before the Y shaped upper breather hose is really soft. I thought that this might be collapsing under boost causing the hesitation.

Any ideas please?

 

[psycho6285]

Dont think the Y shape pipe is under vacum it positive pressure from the breather system, might be wrong tho.

Id go with the CTS, mine did the same, only about a tenner from Eurocarparts, get the newer green one. With it not working right the car wont be running at optimal temp, so ecu will be not be fueling correctly.

 

[rob - 73]

Cheers man, I will try the CTS first.

Is it just a case of removing the old sensor and replacing with the new one. Do I need to watch out for anything else?

 

[psycho6285]

Na its so simply you wouldnt believe. Just pull the C clip take out the sensor, put the new one in and then replace the C clip.

 

[rob - 73]

Further info / update:

So fitted a new Coolant Temperature Sensor, from the dealers as well, I know should have used ECP, didn't what to take any chances... so £32 lighter.

Had a good run down to site and back toady (Glasgow - Kilmarnock and back), unfortunatly the problem is still there, hesitation at 2700-3000rpm and definatly feels like a loss in power. Emissions light is still on.

So yet again I am thinking it has to be a boost or vac leak. As I mentioned before the Y shaped upper breather hose is really soft.

The hoses that go under the manifold (PCV hoses??) are covered in oil, could this be the problem area?

I really do need to narrow this down as I want to be spending money on new suspension and not throwing money at this problem.

Any help / ideas please?

 

[psycho6285]

If the hoses under the inlet are oily then at least one of them has split mate, i had this mate and made a massive difference once sorted.

 

[cupratune]

Right..........had same issue and mine was the maf..take the sensor off and give it a run.

At worst take negative off the car leave for 30min and that will clear the faults.............or get some one with vcds to clear them.

I had signal too low reset with vcds car is running awesome and its not come back.........if you have hissing from the breather pipes get them changed........know a good person that does good silicone hoses for an affordable price.

 

[cupratune]

in addition clean the throttle body and get it aligned!

 

[rob - 73]

Cheers guys, I will check the PCV hoses.

How difficult is it to change them?

How much would it cost to replace them with silicone hoses? And where from??

I cleaned the throttle body a month ago, will do it again.

As always the help is greatly appreciated, cheers

 

[cupratune]

This is the guy i brought from....http://shop.ebay.co.uk/creationsmotorsport_com/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p3686

Brought the tip, full hose replacement for intake and the upper lower etc...........great guy!

Bit of a bugger if you dont have good cutters to reach the oem clips other than that piece of piss

 

[rob - 73]

Well I finally checked under the manifold and found a 60mm split in the lower PCV hoses, it was hidden by a sleeve which covered both PCV hoses.

So I order and installed the replacement upper & lower breather*hoses from Forge. Went for the OEM look with the black colour.

Hesitation now gone completely..

What I did notice while replacing the hoses was that the connecting hoses, (plastic hoses connecting to pcv valve, metal connection to right of the engine and also pancake valve) had what I thought was dirt inside them, although I think this must be old dried up oil residue.

Is this normal?

And what is the best way of cleaning all this gunk out?

I take it the only way if keeping it out would be to fit a catch can.

 

[rob - 73]

Looking to do some engine maintenance over the weekend, so am after some advice on what valves / hoses & connections to clean out.

I have done the throttle body already.

Any pointers please?