Hi.

1.0 AAU engine, 1.3 AAV throttle body and injector, golf elbow and cone air filter. 60,000 miles, new headgasket last month.

Only noticed problems a few weeks after fitting 1.3 throttle body and injector.

Occasionally when I'm coming to a stop and decellerating, I'll put the clutch in and the revs will drop quite quickly and stall the car. Sometimes they drop to a very low rpm but the engine will pick back up and return to idle by itself. If the gear change is quick the engine continues as normal.

This problem seems to occur more when I'm in a high gear at a low rpm, then put the clutch in and the car wants to stall, eg, decellerating from 25 / 30 in 4th gear.

Any ideas? Cheers

Hi.

1.0 AAU engine, 1.3 AAV throttle body and injector, golf elbow and cone air filter. 60,000 miles, new headgasket last month.

Only noticed problems a few weeks after fitting 1.3 throttle body and injector.

Occasionally when I'm coming to a stop and decellerating, I'll put the clutch in and the revs will drop quite quickly and stall the car. Sometimes they drop to a very low rpm but the engine will pick back up and return to idle by itself. If the gear change is quick the engine continues as normal.

This problem seems to occur more when I'm in a high gear at a low rpm, then put the clutch in and the car wants to stall, eg, decellerating from 25 / 30 in 4th gear.

Any ideas? Cheers

I had this problem with stalling when dipping the clutch for absolutely ages, it's quite common. Try cleaning up the idle control valve as it can get pretty gunked up, my car ran perfect afterwards

+1 for idle control valve.

Thanks alot chaps! Will give it a try :)

Looking through my haynes manual, looks like mk3's dont have an idle control valve? =/

Try cleaning your throttle body with some wynns carb cleaner :-)

PoloD.

Thanks, but I cleaned the throttle body loads before I fitted it and it was spotless. However now I think about it I can't remember the car ever doing this on the 1.0 throttle body, but I had no problems with the 1.3 item when I fitted it months back. I don't have the old one to swap and see if it makes a difference

Could try cleaning out the idle screw. On the right hand side of the throttle body theres a small screw, behind the one with a nut on it. Take it right out and clean the fuck out of it, then pop it back in. Try to note how many turns it was, think its 2 turns out from all the way in. May need some fine tuning though.

Still have this problem occasionally. Seems to happen when the engine goes from under load at low rpm to clutch down, it stalls.

Any ideas? considering fitting a 1.0 injector again...

:(

No one? Car is still doing it :(

might need to adjust the TPS on the side of the throttle body.

the throttle swap isnt straight forward. The TPS is set at the factory but is also set for the 1.3 ECU, when you swap the TB you need to adjust the TPS to compensate.

Loosen the 4 security screws and with the engine running turn the TPS so the engine pics up. go for a drive to test it out. keep doing this till the problem goes.

Cool, I'll try it tomorrow, thanks!

What do you mean by engine pics up, the revs increase?

Thanks a lot mate! JJ

Ye, if that doesnt work swap back to the 1.05 throttle body and see if it goes away.

actually before fiddling with the TPS try spraying WD40 or carb cleaner around the base of the TB and see if the engine note changes, symptoms could be a vac leak too.

No vaccum leaks, tested with wd40 and no change in engine tone / speed.

Tried adjusting the tps, but if i moved it either way it made the engine run worse, back in original position now.

I tightened the screw which engages the plunger on the idle control unit, so it kicks in sooner when the throttle closes, which has helped catch the engine when the revs drop quickly, so the engine now picks up again when the problem occurs but the problem is still there.

Any ideas? :( going to look for another throttle body if not

Thanks, JJ

if u need another 1.3 aav throttle body i have two in my garage, pm me if you need one

Hi, thanks but I'm going to revert back to the 1.0 item, just to make sure, looking to eliminate problems caused by the change in TB size.

Most of my polos have had this problem when cold, usually when going up a hill and dropping a gear.