Audi 100CD won't start.

[Spyda]

Dads car is having a cry and refuses to start.

Its a 5cylinder K-jet motor, we have replaced the dizi-cap and cables, checked the spark plugs and checked that its geting spark. Petrol is also getting to it, we checked this by loosening a bolt of the fule line on top of the air box (not the best description :confused: ) Hope it makes sence.

So its got spark and fule, i dont see why it wouldnt be getting air, so why doesnt it start?
Its makes all the normal starting noises appart from it roaring in to life.

Does anyone have any ideas?

[Jmac]

Firstly mate you say its getting a spark - i take it the spark is at the plugs????? Being a KJet i has large fuel pressure mate so when you are cranking is the fuel flying out of it?????? How long have you been cranking it for too????? There is a few things it could be mate but just getting an idea so we can start from the beginning
Cheers,

[Spyda]

Firstly mate you say its getting a spark - i take it the spark is at the plugs????? Being a KJet i has large fuel pressure mate so when you are cranking is the fuel flying out of it?????? How long have you been cranking it for too????? There is a few things it could be mate but just getting an idea so we can start from the beginning
Cheers,

Another important thing, the problem started a while ago, the car wouldnt start when it was left in the sun. When we would try at night or early in the morning it would start but if it was left in the sun it wouldnt start.
No after replacing the dizzy cap, cables and spark plugs it wont start at all. It turns but wont start. (I dunno if this is important but you can feel the air coming out of the exhaust)

We replaced the spark plugs and tested that there was spark by putting a screw driver on the spark plug cable and watching the screw driver spark up.
We didnt test for fuel while cranking the car up, only when it was off and the fuel was flowing out of the loose bolt.
We would crank it for different times, some times short, longest about 10-15sec.

oh another thing, before it stoped all together, it had a rough idel and the idel would become eratic when the car would be put in Drive (its automatic). Park was fine though as far as i remember. It stoped working after we removed the dizzi its self but we put it back the same way it came out, i dont think timming was thrown off.

[Jmac]

So since you had the diz out it failed to start? remember the dizzy is geared and does turn the shaft as it locates into postion. You should take the dizzy out when the engine is firing on number 1. So set up number one to TDC and the centre of the rotor arm should be in line with the notch on the dizzy body.If it is not then turn the dizzy till it is. Then try it. You must make sure that is all lined up especially if you have had it out mate.
So what im trying to say is the dizzy on the outside can look like its in the same posi but the centre shaft does in fact turn out of whack when refitting.
Jmac

[Spyda]

So since you had the diz out it failed to start? remember the dizzy is geared and does turn the shaft as it locates into postion. You should take the dizzy out when the engine is firing on number 1. So set up number one to TDC and the centre of the rotor arm should be in line with the notch on the dizzy body.If it is not then turn the dizzy till it is. Then try it. You must make sure that is all lined up especially if you have had it out mate.
So what im trying to say is the dizzy on the outside can look like its in the same posi but the centre shaft does in fact turn out of whack when refitting.
Jmac

So even a little movement form the original position will cause it to not start?

Whats TDC? and what do u mean by engine is firing on number 1?

[Jmac]

If it moves minimal amount it should start or at least fire. TDC is Top Dead Centre this is when the Piston is at the very top of its stroke and on the the cusp of going back down. Absolute top. When i say firing on number one , number 1 piston is at Top Dead Centre. Crankshaft and cam shaft marks should line up at this point. Then you set up your distributor, there is a timing ntch on the Diz body that lines up with the Rotor arm. Mate that could be a number of things then if all this is right. Like i say if the dizzy has moved a bit it should still at least fire, maybe not start but at least think about it.
Mate loosen the FEED pipe on the FUel meter head where all the pipes are. There is an arrow on the meter head ( the feed one faces the meter head) Take it off and get a container or a fuel can or such like. Disconnect your coil as we dont want any sparks. Then have someone crank her over and watch to see what how much fuel your are getting. It should come out at force. Sounds to me you have a spark, timing upset (maybe) but fuel is the issue here me thinks. If the fuel test proves you are getting fuel , you will need to have the pressure checked. You mentioned there was fuel when you checked the lines. This is the case as the system has a non return valve keeping a residual pressure in the lines.
See how you go
Jmac

[Spyda]

If it moves minimal amount it should start or at least fire. TDC is Top Dead Centre this is when the Piston is at the very top of its stroke and on the the cusp of going back down. Absolute top. When i say firing on number one , number 1 piston is at Top Dead Centre. Crankshaft and cam shaft marks should line up at this point. Then you set up your distributor, there is a timing ntch on the Diz body that lines up with the Rotor arm. Mate that could be a number of things then if all this is right. Like i say if the dizzy has moved a bit it should still at least fire, maybe not start but at least think about it.
Mate loosen the FEED pipe on the FUel meter head where all the pipes are. There is an arrow on the meter head ( the feed one faces the meter head) Take it off and get a container or a fuel can or such like. Disconnect your coil as we dont want any sparks. Then have someone crank her over and watch to see what how much fuel your are getting. It should come out at force. Sounds to me you have a spark, timing upset (maybe) but fuel is the issue here me thinks. If the fuel test proves you are getting fuel , you will need to have the pressure checked. You mentioned there was fuel when you checked the lines. This is the case as the system has a non return valve keeping a residual pressure in the lines.
See how you go
Jmac


Thanks mate, ill give it a go and see what happens, hopefully its just a matter of timing.

Any ideas why it wouldnt start when it was left in the sun?

[MIK]

this probably has nothing to do with anything, but my old datsun with twin SU carbies, in hot weather teh fuel would vapourise in the carbie, you'd turn it off and wouldn't be able to start it for an hour or so...

my rx7 on the other hand had teh opposite, cold weather, fuel would free in the carbie.

like i said probably unrelated, but i have heard of this heat/vapourising fuel a few times, since your mentioning hot/cold...