S3 WONT START

[steve wilton AM]

hi had no problems with the car,took it out for spin yesterday ,started fine run normal.stopped in the town,away from the car for about 15 mins ,went to start it but it just turned over and over but didnt fire.tried several times then looked under the bonnet for obvious signs!tried again it fired a few times although intermediatly,tried again and it went.thought id put more petrol in it as was supposed to be taking it to a show this weekend,left it running as i was filling it but revs dstarted dropping then it stopped.tried to start it again same thing just turning over,left it for 10 mins then it went.gave it a good hard drive home ,no lack of power no misfire seemed fine.switched it off when home, tried starting it again,just kept turning ,same thing again.when it went took it to local mechanic,we tested spark from coil and to plugs ,all ok,removed fuel line into efi turned key and plenty of petrol came out,plugshave good spark and wet petrol on them aswell .any ideas what am i missing .thanks

[spivvy]

check the connector under the steering column isn't shorting out

[Gerald-TVR]

Yep might look like this!!!!

[tvrgit]

steve wilton AM said:

we tested spark from coil and to plugs ,all ok,removed fuel line into efi turned key and plenty of petrol came out,plugshave good spark and wet petrol on them aswell .any ideas what am i missing .thanks

None of those things would be ok if it was the ignition connector. No ignition = no spark, no fuel pump.

It MIGHT be that, but it's not symptomatic.

(I don't know what it IS likely to be, there are a number of possibilities - but if you have fuel (as you have) and you have a spark (at the right time), it should go!)

[steve wilton AM]

thanks ,as to tvrgit how about the spark not being at the right time?can this be checked.

[steve wilton AM]

just got back from garage,looked at connection behind s/wheel everything fine no burns ect, could the ecu cause my problem ?can it be checked

[tozerman]

Do you have an immobiliser fitted ? because, if when you have a spark and fuel the car runs fine and when you don't have both it will not start it could mean that the imobilser isn't working properly, might be worth checking it out you never know, good luck
Cheers.....Tony..

[steve wilton AM]

there is one fitted but its never worked even for the person i bought it from.but its turnig over as we check spark an fuel ,if somehow the immobiliser had come on i think it would stop the engine electrics(i presume)

[steve wilton AM]

update, today we had to move the car so mate could use his lift.befor we started pushing tried to start it after a couple of attempts away it went so drove it back home,runs fine.switched it off and tried to restart it took lots more engine turns but started 3-4 times in a row.noticed the revs were higher and sometimes stuck at 2000 revs untill bliped throttle,have been trying to locate a gunson 4160 to buy ,tried ebay but can only bid ,would like one asap any views

[Gerald-TVR]

Halfords?

[steve wilton AM]

there is a long "sensor" on the front of the fuel efi unit,inside it is a small push rod is this what controls the throttle? when the car is running and its reved the throttle tends to stick for a while.when we took the front part of this off ,the sticking throttle stoped.where can these be bought.

[tvrgit]

You're describing the same problem but in a completely different way from your other thread. Is the throttle itself sticking or just the revs remain too high? Please let's stick to one problem one thread because it's easier to follow.

[steve wilton AM]

the cable is free,the tick over is slow to drop and sometimes sticks,when the sensor cable on the coil like unit at the front of the efi is removed it ticks over fine and doesnt get stuck,i dont know if this is part of or all of the reason ive had over the past couple of days so posted it as seperate issue.

[tvrgit]

if you disconnect the idle speed valve (that I refer to in the other thread) you put the ECU into diagnostic or "limp-home" mode where the engine disregards many of its sensore inputs and pre-programmed maps - so that can mask the real fault - in other words, just because you disconnect that, and the problem goes away, doesn't mean that's where the problem is.

I would still start by taking it off and cleaning it though and then see where we go from there.