Nissan Repair: Intermittant starting problem


Question
QUESTION: Hi Michael

I used to volunteer on this site, so thanks for you time and any advice is appreciated.

I recently bought a 2004 Hyundai coupe (no experts in that category) and three days later it won't start.  It cranks but won't kick in.

The mech for the garage I bought it from came out but doesn't know what is wrong.  The first time he came out, he pressed the alarm fob a few times and it started when he used the key about 20 mins later.  Turns out the alarm is disconnected though so it can't have been that.

Second time he couldn't get it going.

Third time he came out with a diagnostic plug-in and he managed to start it.  However, no fault code was shown.

I sat at home and tried to think of what he did on two occasions but not the third and I thought that it may be because he left the key in the ignition.  So I tried that - put the key in the ignition, turn it to ACC and leave it for 20 mins (any less and it doesn't work).  Then take the key out put it back in and it starts.  I know very little about cars but could it be an immobiliser issue?

The garage is becoming a little shady about the problem and I'm probably going to have to get my money back.  I'm guessing they got it on a part-ex and just want to pass it on.

In case I want to keep the car though, my questions are...

Is it likely to be the transponder key failing - what does leaving the key in the ignition actually do (do it reprogramme it, etc)?  Would a replacement key be good enough?

Could it be something more expensive - an ECU failure, etc.

Can the immobiliser be bypassed (if it is a an immobiliser issue)?

Why would no fault code be shown?

Any help appreciated, I like the car but need it for work and I travel all over the country so need a car I rely on.  I work with kids in child protection so I can't have a random kid stuck in my car 300 miles from home and it won't go anywhere lol.

Should I just return it?

ANSWER: as we have a expert in our garage on Hyundai could you tell me the model and anything else as we are in the UK and it may not be a European model but we will try to help you out

---------- FOLLOW-UP ----------

QUESTION: Hi Michael

Its a Hyundai Coupe 2.0 SE 2004 - gen3 I think.  It looks like its been well looked after but has had 7 owners, 5 in the last 5 years.

I'm trying to monitor the situation to see if it's happening at any particular time.  It seems to happen when its raining (x6), apart from one afternoon when it wasn't.  

The engine turns over but won't start, the battery's got plenty of charge and all the lights on the dash come on.  When it does start there are no warning lights present and when it doesn't start the 'car with a key in it' symbol isn't lit up.  When going it drives well.

It feels like an issue where the key isn't being recognised and the immobiliser isn't disarming - leaving it in the ignition and turning to ACC for 20 mins was a guess and it works for the time being but isn't a permanent solution.  I've read that sometimes a leaky windscreen can cause this issue but can't see any leaks and there's no moisture inside the car.  A faulty crank position sensor has also been mentioned quite a bit but I have no idea what that is and don't know why this would affect the security system (if it is the immo).

The aftermarket scorpion alarm/immobiliser isn't connected.  I have a spare key that I was told needs coded - it doesn't look like a new key as it's worn and I'm wondering why the spare lost its code and whether its connected.

My wife's a manager of a law firm and it was suggested I can't get it fixed myself because then I would be liable to pay the bill and also that would be me accepting the fault making it difficult for me to return it.

I would like to keep the car but if its likely to be an ongoing problem or an expensive fix (seen prices of £700 for new OBM, etc) it'll have to go back.

Thanks for your time, Marc

Answer
Hi Marc if you could try the following the remote of your alarm it contains a small battery try replacing the battery or cleaning round the contacts if this wont work it may be the transmitter inside it is not talking to the module inside the car if possible try to obtain a loan of a similar module and remote fob then plug it in to see if it works it will be down to the remote control not talking to the module inside the car and thus not allowing the car to start. where the car has a small light to let you know if the alarm is mobilized try to sit in the car and turn it on and off to see if the light comes on or not if it turns on and off then try to see if the car will start