Poor performance/mpg help needed please!

[Golden_Gaze]

Hi all,

I got 2 '88 gti 8v's, both pb engines, one of which has 126k, and runs like a dream, the other i've recently purchaced, has done only 82k and for the life of me i cant get it running properly. Was hoping someone could offer some suggestions

Its a bit sluggish on acceleration, not quite as crisp as it should be, uses sh!tloads of fuel, and on decelleration, revs are VERY slow to drop off to around 1000rpm, sometimes sticking around 2000 rpm - get the feeling something is sticking somewhere, but i cant find what. Throttle mechanism moves freely and looks in order.

Have replaced ignition system, cleaned ISV, and associated breather hoses, cleaned throttle body, idle screw etc, checked hoses for leaks/cracks etc. all the stuff thats posted on here. I'm suspecting maybe air flow meter - i have a spare - can anyone tell me if you have to re-adjust mixture setting once new meter is fitted? Anyone had any similar experiences? Cures? Sometimes, the revs simply refuse to drop off, only restarting car seems to cure it temporaraly. Urgent help  on this matter would be greatly appreciated.

Many Thanks,
Paul

[Mart8V]

Knackered temp sender?  It is the screw in one on the 88 digi (if it is the same as mine). 

Well worth a try if not already done......

[Golden_Gaze]

cheers, but already tried that. Have noticed car runs cool tho - only just gets outa first white mark on temp gauge - other golf's usually between there, and halfway. Computer says oil temps 80 degrees on normal running temp, which i'm thinking is way too low? Gonna try new thermostat too - guess it cant hurt.

[[han]]

serves you right for havin too many golfs!  hope ya get sorted babe!

[Golden_Gaze]

  cheers, spanner! Gimme them big bumperz! U know u want to!

[jezza16v]

Hi, before you attempt to change the stat read my post on page 2 '16v water pump'. The front bolt of the thermo housing seems to come out OK because its captive, the back bolt is a through bolt and the back of it gets rusted into the alloy pump casing. Try and get a small wire brush on the back end of it and give it some penetrating oil a few days before you attempt it. If it still shears you might be able to drill the old bolt out if you take the pump off. Don't try and drill it out while in place like I did, the drill shot straight through and cracked the edge of the pump casing. I've read on other forums that this is a pretty common problem and often ends up with getting a new pump - about £25 from GSF, I got mine for £10 on Ebay. My 16v has been on the new stat for 3 days now, a complete tranformation, good MPG & good heater now - Good Luck 

[rubjonny]

Check the timing, and loosen the screws holding the idle switch to the throttle body, its underneath and you can only get to it when the inlet boot is removed.
You want to adjust it so that it only just clicks when the throttle is closed, on mine it was slightly too far in and was holding the throttle open slightly.

Also swap the ISV on from the other GTI, they can still be faulty even after you clean them

Did you replace the blue temp sender with a genuine VW one?

[[han]]

you know i wont give them away! would prefer them on my car, but they need sprayin! no poin in you buyin them if ya dont get car fixed! and its hannah to you! 

[Golden_Gaze]

Cheers for yer advise, chaps, and hannah.

Yep - tis a genuine vag temp sensor - just tried swapping ISV' round, and no difference, timing's spot on. Gonna try airflow meter next i guess, get the thermostat sorted, and take it from there. Sick o people looking ay me like I'm a knob when it's revving its ass off of it's own accord at traffic lights!

Han - get them bloody bumperz painted - mines Atlas grey too! Do the work, then I'll take 'em off ya hands! lol

[[han]]

mines not atlas grey... we had this convo!