I have the 1.4 16v engine, and its inherrent never ending problems. This has been going on about 6 months or so now and i can find no solution so am looking for some pointers.

Symptoms;

Inconsistent idle, while its not hunting a large amount you can definately feel and see the needle dipping and picking up again while at idle

Feels alittle jerky when cold and pulling away, nothing drastic

Randomly judders, usually while accelerating, so even after a corner and under slight load to pick up speed again it will judder for probably 10 seconds or so then will pick up again

Will sometimes stall at a junction/lights, again randomly

Not using any significant amount of oil

Things done already;

EGR (brand new valve) is blanked off - fault light on due to this

Vag-com has found no error codes (other than egr) stored

Coilpacks (all 4) < 6 months old

Spark Plugs (all4) < 6 months old

Throttle body is clean and aligned

I can only think of the actual coil itself, but i am unsure where it is. Thought about a loose or damaged earth but the easily accessible ones all seem ok. Battery has good voltage. Abit stumped now to be honest, any ideas on other things i can check or replace before i just trade it in :(

Sorry for the long post !!

no one able to offer some advice or options to investigate ?

Check the coolant temp sensor is stable and not giving readings all over the place.. one of the most prone to ailing parts that effects running.

I'm not sure this is your problem but defiantly worth checking it doesn't suddenly tell the car it's -80'c.. mine kept doing this and it messes the fuel to air mixture all up.

Cheers fella, worth swapping - will grab one at the weekend. Got to the point of needing to try anything ! lol

+1 with that. If not, try disconnecting the MAP to see if it runs any worse. If it _doesn't_ then that's faulty too / instead. As both sensors suffer incipient faults, troubleshooting through fault codes can be a bit hit-and-miss since 'pending' fault codes (starting with P) get wiped after a certain amount of time...

HTH

another vote for map sensor from me too i'm pretty certain it's the map sensor which is causing a random missfire on my 16v engined pickup but i've not had a chance to investigate fully yet

I've found the coolant sensor, but where abouts is the map sensor on these engines ??

Not had much to do with these before sorry !

It should be a square-ish item with a connector on one side, held in a hole in the inlet manifold (top, rear of engine, under throttle body) by either a couple of Allen bolts, or a couple of Torx screws. Probably easier to feel than see, so make sure the engine's cold!

Spot on cheers fella, i'll get both of the coolant and map sensors out and get new ones sorted

Fingers crossed, can start spening on wheels rather than boring stuff if it works

The prices for genuine and third-party coolant temp sensors are pretty similar, but you can get MAP sensors off eBay for a lot less than from the dealer. The MAP sensors are quite fragile, though, so after getting two faulty (squashed) mail-order ones in a row, I opted to get a genuine one from my my local factors, even though it cost more...

My wife's car was a completely different animal with a new MAP in, by the way - it even got a massive hike in MPG, so it's probably paid for itself in fuel a couple of times over by now!

HTH