ABF issue

[Screech16v]

Started being a little jittery on light throttle,always starts no problem ,still have full power,just when im tootling along at low speeds it feels a tiny bit jerky and its annoying the heck out of me,also has a random misfire on tick over,just the odd pop now and again only noticed this when warm, the engine has been faultless up to now,any one had similar symptons,cheers mark.

[Sprakie2008]

Checked your compression mate?

[Rmachines]

Started being a little jittery on light throttle,always starts no problem ,still have full power,just when im tootling along at low speeds it feels a tiny bit jerky and its annoying the heck out of me,also has a random misfire on tick over,just the odd pop now and again only noticed this when warm, the engine has been faultless up to now,any one had similar symptoms,cheers mark.

 To be honest the MK3 engines do run a little bit lumpy,  90% of MK3 engines i hear will burble a little, to me its just how a golf GTI Should be!  Shouldn't be like a misfire though,  it sounds like it could be something as simple as HT leads, dizzy cap etc..  so start with them,  It depends what you are used to, some engines tick over very smooth, if you used to that an ABF engine might seem worse than it is,  as you say its  a bit jerky i would start with the basics,  spark plugs, dizzy cap and rotor arm, HT Leads,  if that makes no difference, could try another known working coil, but unlikely that would be just at idle.   I always say start with the service items,  A fault code scan is always wise,  as something like a failing cam position sensor could be dropping the signal causing it, but its impossible to know that without the ECU Telling you.  Even the temp sensor could do this if its causing to run rich, but i would like to advise you to replace sensors unless they through a fault code,  as thats just throwing away money.

[Screech16v]

Ive run this motor for nearly 2 years now and allways service it with genuine /oe items and im used to how this motor runs and sounds so know straight away when somethings up,give it a scan today and no codes were thrown up oil and filter changed 2 weeks ago ,genuine plugs last week,beru cap and rotor 6 months ago,fuel consumption seems about normal,i have never changed the ht leads so may start there,the misfire at idle is random and very few and far between(usually rock steady and crisp) so maybe a ht letting the odd spark escape,i did think compression at first but it allways starts first time and is making good power as my boss found out at the lights in his mk1, im trying not to spend any money on this as ive just aquired a 60k 1.8t and funds need to go towards the conversion.thanks sparkie and r machines,will tinker on.

[Screech16v]

Ok forget about the tiny now and again miss on idle as im sure this is unrelated to the slightly juddery running,it feels like the engine is rocking forwards and backwards very lightly,put the engine under load and its smooth,tick over is fine,and starts on the button everytime,to me it feels fuel/air related,ive scanned for codes and nothing again,im pretty certain this is not ignition related,anymore ideas peeps!

[Leon27]

Just some thoughts on things to check:
Check the wiring to the throttle position sensor and idle switch, the loom runs over the exhaust manifold and gets hot/burnt easily.
Check that the leads are pushed home, an E30 had a similar problem at work where the plug wasn't allowing the lead to make good contact (Genuine Plug and Gen. Lead!)
Vac hoses - one from the ECU MAP sensor to inlet manifold/PCV to inlet/Fuel pressure Reg to inlet

Clean the idle valve and whilst you're at it the throttle body for good measure

Does the rev counter register and show whats going on or is it ever so slight?

[Screech16v]

Hi leon thanks for the reply,will check the wiring to the tps and clean isv tomorrow,all vac lines are silicone i did them a while ago,and cleaned the tb a couple of weeks ago,rev counter shows no sign of the problem as its so slight but very annoying!

[Khare]

Clean the idle valve and whilst you're at it the throttle body for good measure

This is what I'd do first before anything, especially throttle body.

[danmusic24]

If you find the problem let me know pls,mine does the same thing don't see it as a big problem just a little annoying!

[Screech16v]

Well checked the wiring to the tps and its ok although the shielding conduit stuff is crispy from the heat,cleaned the isv,then whilst checking the bay found the earth strap from the coil to the head was loose,ive driven it since and it does seem to be better so hopefully... thanks for all your help on this guys,this forum rocks!