Light Throttle Hesitation Theory - *Technical Input Please*

[longman]

Hi all.

Since buying my LC in March, it has always had a hesitation in power when at light trottle. Hot or cold, what ever gear but more noticable at low revs and always when there is little or no boost.

I have searched on here and a lot of people seem to have had the same issue. Reccomendations have been N75, MAF and DV... The usuals but none of these have cured my problem.

Just wondered if anyone can shed some light on my theory that:

When there is no boost from the turbo, the engine is sucking the air in and causing a vacuum. Could this lift the piston in the DV - acting against the spring? If the spring is not strong enough, it could allow any pending boost pressure to dump out of the DV and back through the system again, causing a drop in air flow and a hesitation in power.

As soon as the turbo is boosting properly and is spooled up (from more throttle) there is no vacuum present at all and the problem will not occur.

A fix for this, simply using a more forceful spring I would guess, from what searches etc say..?

My LC is standard with the Yellow spring, therefore, this was not something I had considered. However, I would like some feedback from the more technical and knowledgable just to see if my theory is anywhere near feasible!!

So.... Hit me!! Am i speaking ??

 

[evo2345]

im experiencing the same problem the car seems to hesitate and jerk and low revs then when boost comes in its fine,

 

[Wilko]

If you have a forge dv, sercvice it and it should improve it.
Mine does it when my dv needs a sevice. The piston movement gets a bit sticky.

 

[longman]

If you have a forge dv, sercvice it and it should improve it.
Mine does it when my dv needs a sevice. The piston movement gets a bit sticky.

I have mate and tried that...

 

[TheSultanofPing]

I have the same problem with mine and its completely standard. Did I read somewhere that a remap cures it?

 

[longman]

I hope thats not all that cures it, as I am sure this wouldn't have come out of the factory like it. I might try a stronger spring in my DV to test my theory out....

Its common thing by the sound.

 

[beezasport]

I've just pulled my split-r out of the tip and bunged the tip so its venting to atmosphere and the problem seems to have gone away. i've got a propper atmos DV on its way to me so im going to try this and see how it goes from there if that runs ok i'm not sure what would be causing the problem. I know its not good to run on full atmos as it can cause problems.

 

[corradophil]

I have the same problem with mine and its completely standard. Did I read somewhere that a remap cures it?

Mine has only done it since it's re-map

 

[longman]

I've just pulled my split-r out of the tip and bunged the tip so its venting to atmosphere and the problem seems to have gone away. i've got a propper atmos DV on its way to me so im going to try this and see how it goes from there if that runs ok i'm not sure what would be causing the problem. I know its not good to run on full atmos as it can cause problems.

Yeah, you'll get a light on the dash if there is no charge air going back past the MAF from what I gather.

 

[traumapat]

have you vagcommed it? i bet you have but dont overlook any fault codes even if they dont seem connected. temp sensor?

have you tried a tb reset?

i had issues when cold... but more jerky than hesitant. fixed eventually by dielectric grease on the maf connection. i think moisture was getting in there and arching.

i still get the odd hesitation/ power loss on steady throttle at approx 3k revs. is it that your experiencing?

 

[longman]

Yeah, thats it, perfect at full throttle but the power occasionaly dies when you hold the throttle still at 2-3K revs - only occasionaly... VAG-COM says nowt and have tried MAF changes and have done the same with the Dielectric grease on the connecitons.

Its not a big issue, just an irritating characteristic that I would like to bottom out!

TB and ECU reset.... Done and didn't really help although the experience was a little smoother!!!! - Hesitation still damn well there!!

 

[traumapat]

Yeah, thats it, perfect at full throttle but the power occasionaly dies when you hold the throttle still at 2-3K revs - only occasionaly... VAG-COM says nowt and have tried MAF changes and have done the same with the Dielectric grease on the connecitons.

Its not a big issue, just an irritating characteristic that I would like to bottom out!

TB and ECU reset.... Done and didn't really help although the experience was a little smoother!!!! - Hesitation still damn well there!!

yep mines the same and to add to the list... 2 remaps, different ecu, maf, temp sensor, dv`s ect and nothing has made a difference. i drove myself nuts trying to work it out.... gave up.

the only answer is to drive at full trottle everywhere frightening in the multistories though

it feels like the engine has suddenly reached the requested power , youve not asked for anymore so it suddenly pulls back?

i now treat it as a quirk. although your dv idea has got me going again

 

[beezasport]

Yeah, you'll get a light on the dash if there is no charge air going back past the MAF from what I gather.

not had any probs running the split r in atmos ill let you know how i get on with the bailey.

 

[longman]

Had a slow day at work so started thinking and drawing doodles etc.....tried to work out what could be causing it.... You never bloody know...

I have posted this on the Forge forum too so I would be interested in the experts input!!

I am probably talking nuts but its got to be something...

Laughed at the full thottle gag.... Might raise a few eyebrows in my Ville too!!

The most irritating quirk these cars have.... Still love mine though!!

 

[Avant4me]

This sound more like something related to the throttle position sensor, is there any adjustment availalble in it?

 

[beezasport]

Charge air pressure sensor G-31 has been mentioned on another post. iit's on top of the intercooler but i dont know what this does or if anyone has had a fault with these previously.

 

[jonathanp]

G31 is the map sensor, its what gives for the readings for boost pressure on blocks 115, 118 etc

 

[longman]

This sound more like something related to the throttle position sensor, is there any adjustment availalble in it?

Its something I had thought of but I would assume that would be a constant problem.

I might get it checked at some point, just in case. Any idea how it works?

 

[chriswilks]

this sound similar to what my car is doing at full throttle at high speeds (80+) i dont understand why tho!!!mines been remapped with just a filter.......however it seems theyve installed winows 95 on it coz its hopeless!!

 

[CupraUK]

Mine has only done it since it's re-map

Mine too