Engine hesitating

[Pander]

While on the drive to UD, sitting at around 70-80 when I went to put my foot down a little, the car didnt want to know, just started shaking. It was only until I floored it that it started moving. It didnt happen all the time though ? It did do it more on the way there than it did on the way back though, but if anyone could shed some light on what it could be, it would be much appreciated. or however you spell it. oh and the car is a 8v gti(AGG)

 

[vngtx]

does it rev past 5k?

 

[Pander]

yeah, it feels fine 99% of the time, picks up well keeps goin until the limiter, but oddly on a motorway at around 3-4k revs it just doesnt wanna go, but even that isnt all the time just quite random.

 

[vngtx]

mine does that aswell. might just be a glitch in the air/fuel ratio at certain temperatures. unless its a sign the coilpacks going. ive had to replace so much that i only thing left that i know is faulty is the dizzy.

 

[Pander]

Bit of a **** map on vw's part then lol.

 

[Pander]

that said, im still going to replace all the ignition stuff.

 

[vngtx]

when it hesitates, is it on a long journey? and the engine warm?

 

[Pander]

thats the first time iv noticed it. and yes the engine was warmed up, coolant was bang on the middle, and oil temp was 82

 

[vngtx]

you should run diagnostics on it and see if anything comes up. i had air intake sensor, air flow meter, n80 charcoal filter valve, dizzy hall sender and 2 wires shorting out that came up on mine.

 

[Pander]

if i can get hold of a code reader then i will, its just odd that its only on part throttle
it still flies when I floor it. If i cant get the fault codes read, i think il try running it without a MAF and see if that makes it better.

 

[Pander]

Still need help. I drove down to Bristol and it keeps doing it nearly all the time, partial throttle and it just judders and goes nowhere quick, but give it full throttle and it takes off again. Or when it hesitates if I come off the throttle and back on again its alright. Is there anything on the throttle body that measures throttle? im not to familiar with these engines so any pointers or advice would be much appriciated. Cheers

 

[M1KEH]

Clean your throttle body.

 

[Pander]

Yeah I will do, but I read a thread on here somewhere, when they cleaned it out a load of other things when wrong, cant remember who but I'll be careful where Im spraying. Whereabouts in bristol are you from ?

 

[br0wny21]

does it tend to do it more when its warm? my car started doin it on motorway trips it felt like the engine was misfiring has the car got warmer it got worse i changed coil packs on mine and it runs bob on id try that its not much to change and it will run better too

 

[Pander]

On my final drive home from bristol today (love that place) it didnt do it once ? and i also got a lot better mpg, 32ish when it was hellishly bad and today I got 37.6. To be honest, by the time I get to the motorways its always warmed up so I cant really notice much. Im sticking a coil pack and all other ign/electrical on it next weekend anyway so should be interested to see if a coil pack cures it. do they go quite commonly ?

 

[vngtx]

yes. thats a definate yes. seat coilpacks break more often that kitkat addicts.

 

[Pander]

i bet its that then.

 

[Caffienated]

Bit of a **** map on vw's part then lol.

At those sort of speeds (70-80 motorway) the AGG is totally in it's element and should be super responsive. Tickling the throttle should work smoothly and really flooring it even in top gear without bothering to change down an AGG should pretty much take off. Mine does. (when it's not cutting out... will get to the bottom of that this weekend)

From your symptoms I'd be considering overfuelling, and wondering about quality/timing of sparks or airflow restrictions. So if you have ignition components available, swapping might be worthwhile, and likewise cleaning out TB/checking air filter's not blocked and MAF's playing nicely. If it was an old school carb engine, I'd probably be having a look at the vacuum advance, too...

I don't see anything much wrong with the OE map tbh when run with standard box and engine... I quite like the torque down low where it's useful in real life...

 

[Pander]

im 99% convinced that the TB has got too much crap on it. since iv last posted iv changed plugs, leads, dizzy cap and it still hesistates now and again.

 

[GTI-CRAIG]

i had the same issues with mine ......but mine was worse it happend all the time when engine got to opp temp was limp no power at all.......... this is what i did after i noticed that the air filter housing was spilt ................
take the throttle body off clean it out take the air flow meter off un-screw the black box on the top i used plyers to get mine off as there a funny size hex/with a nipple in the middle ..... then get some cotton ear buds with some white spirit or carb/brake cleaner and carefully clean the 2 rugby post shaped diodes re- assemble and see what its like ......hope this helps