205 1.9 GTI Engine problem

Hello all,

I have a pug 205 1.9 GTI. My problem is as follows;
The throttle seems to be either on or off, by this I mean it is very
difficult to drive the car smoothly; if I try and apply a small amount of
throttle the car will jump foward. If I try and hold the car at a steady
speed (at low speed and low rpm) the car seems to jump along like a rabbit!!
Therefore I find I have to ride the clutch far too much. I know the 205 is
known for being a bit lumpy when ticking over but this is problem I have is
not normal. Its as if the throttle has no sensitivity...it feels like its
on or off!

The wiring under the bonnet is a bit of a mess...due to some monkey
installing a reconditioned engine and gearbox. A mechanic looked uinder the
bonnet and said my crank sensor wire was not connected! surely the car
wouldne run without the crank sensor connected??

Any help and ideas are much appreciated,

thanks

Jon

 

Hi,

Worthes a check of throttle sensor position, IMO. IIRC, should be on the
throttle body, but I haven't seen GTis for a while.
Hint : the Bosch L-Jetronic is an analog fuel injection system fit to many
cars between early '80s and mid-'90s. 205GTi, 505GTi, 405SRi are the most
common at Pug's.
This system only knows 3 modes which are commanded by the throttle : idle
(idle sensor active), linear (idle & WOT sensors inactive) and WOT (Wide
Opened Throttle, WOT switch active).

May well be your problem !

 

Or the throttle cable is too tight. You need a certain amount of slack
in the cable before it winds round the throttle drum. Check and adjust
if necessary.

 

Hi,

I may agree, but IMO it wouldn't idle then - would mean that pedal off the
engine runs in "linear" mode, this involving a high idle. But it also
worthes a check.

 

I didn't mean as tight as that, where it holds the idle too high. Just
tight enough to affect the throttle sensitivity, say in stop start
traffic. Quite common on a 1.9 rather than a 1.6.

 

Practical Classics magazine run some of these cars and have had the same
problem, one good fix is to have a 'Superchips' upgrade to the ECU, it also
helps to have the air mass meter cleaned and the throttle potentiometer
cleaned or renewed.

Andy