polo juddering again

Chat about your 9n Polo (inc GT and Fun)
Post Reply
dizzypolo
New
Posts: 20
Joined: Sun Jan 27, 2019 1:24 am
Drives: 9N 1.4 2004 petrol
Location: Nottinghamshire

polo juddering again

Post by dizzypolo »

Some weeks back I posted here for some help with the running of my car.

Since owning the car I have done a massive array of work, and up till recently the car was running really well.

Basically on doing about 100 miles on the motorway, the loss of power returned, I have already changed the Coil packs, plugs, full oil service, air filter, fuel filter etc. The problem now seems to be more noticeable when in the lower band of revs, from 1800 to 2300 rpm.the car sometimes will suddenly jolt, loose power then sometimes putting down more gas will then make things go normal.up until the other day this was only very slight, then it went really bad. Couldnt get past 50 Mph in 5th gear, changed down, could go alittle quicker.

My firtst thought is that the fuel might be the issue or crap in the tank, when this happened I had 2/3 of a tank if Asda fuel, maybe it will run better on a more expensive fuel? I also havent cleaned the EGR yet? Will it be worth doing this?

One thing I did find is on the way back from work the problem had 99% disappeared and only felt it very slightly when doing 40 Mph in 5th.

any help is appreciated.
RUM4MO
Bling Bling Diamond Member
Posts: 5859
Joined: Sat Dec 30, 2006 9:12 pm
Drives: B8 S4 & 6R/6C1 1.2TSI 110
Location: Mid Lothian

Re: polo juddering again

Post by RUM4MO »

I've forgotten what you did first time round in an earlier related posting/thread, but in my experience, the EGR valve does not get dirty on these petrol engines - it might fail for some reason, but mainly it is the port on the throttle body or the adaptor below the throttle body that gets clogged up along with the MAP sensor.
Most really nasty issues will end up with the fault light being switched on - another thing which I've never had trouble with is the throttle pedal "sensor" ie the part that relays the throttle pedal position to the ECU etc - these cars have "drive by wire" throttles.

Edit:- which brand of coils have you bought, and from where?
bvs
Silver Member
Posts: 271
Joined: Sat Feb 13, 2016 7:56 am
Drives: 02 1.4s 16v
Location: perth

Re: polo juddering again

Post by bvs »

Which engine type/code ?
dizzypolo
New
Posts: 20
Joined: Sun Jan 27, 2019 1:24 am
Drives: 9N 1.4 2004 petrol
Location: Nottinghamshire

Re: polo juddering again

Post by dizzypolo »

RUM4MO wrote: Sat Mar 09, 2019 10:00 am I've forgotten what you did first time round in an earlier related posting/thread, but in my experience, the EGR valve does not get dirty on these petrol engines - it might fail for some reason, but mainly it is the port on the throttle body or the adaptor below the throttle body that gets clogged up along with the MAP sensor.
Most really nasty issues will end up with the fault light being switched on - another thing which I've never had trouble with is the throttle pedal "sensor" ie the part that relays the throttle pedal position to the ECU etc - these cars have "drive by wire" throttles.

Edit:- which brand of coils have you bought, and from where?
The engine is a BBY engine.

I fitted the bosche coils.

Update - the juddering is has now calmed down after fitting a new MAP sensor, it stopped juddering when accellarating. The only problem I am now left with is when the car is going at a cruising speed at low speed - example in 3rd gear at 2000rpm about 30-33mph, when only slightly touching the gas pedal, I will feel slight judder / power loss. this will go away as soon as i apply more gas and only happens around the 1800-2000rpm range..


My thoughts are that it may be one of the following thoerys. 1. Changing the MAP sensor, is sending different data to the ECU, and the ECU may need resetting to get it to relearn the settings, Ive heard people say you can unplug the battery for 30 mins, to force a reset, this did not help.

2. It could be the throttle body alignment, and it needs re calibrating as i did clean all the crap out some time ago. Ive heard there are 2 ways, something online suggested to put the key in, turn the car to "acc" and leave it 3 minutes. (This sounds like rubbish) or use VCDS to force a recalibration.

Id be very interested to hear if anyone else have had these issues.
Post Reply