QuestionQUESTION: Hi, i drive a Audi A4 1.8T, 2001, which i'm having difficulty starting when the engine is warm, there is also a strong smell of petrol as though the engine is flooding. Any help would be greatly appreciated
ANSWER: Well it definately sounds like flooding the reason is why,
what is the current mileage of the vehicle?? Does the engine turn over properly or is it sluggish?? Has the power changed for the worse?? Any other noticable driveability problems??
lots of things can cause flooding.
When was the last time the service was carried out?? sometimes a major fault can have a very simple answer like a clogged air filter that restricts air or even a bad tank of gas!! (bad fuel doesn't ignite as easily causing hard start and in the long run detonation and engine damage)
Id start off with the spark plugs because they are the easiest to verify and also cheaper to replace then the other options, remove them and check the condition when you have the hard start, if they are wet then that would confirm the floding, If they are wet then you have to find out the exact cause, if the electrodes are worn out then it makes it harder for the spark to jump through a bigger gap which could mean that the fuel being injected into the cylinders is not being ignited and there fore causing the hard start, replace them if in doubt. as a guide Audi service intervals are 40K Kms for the normal carbon tip plugs and 60K kms for the platinum tip ones, ( the platinum tip ones have a fine point like a needle while the carbon tip ones have a thick black tip).
After replacing the plugs if the problem still persists then move onto the injection system, maybe the injectors are faulty or dirty and are 'dribbling' fuel when the vehicle is parked for a while while hot there by causing the plugs to get wet. the only way to confirm this theory is to have them tested with a specialist or replace them with 'known good ones'.
Let me know how it goes.
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QUESTION: Hi, the mileage is 100,000 with a full servive schedule. the last service was at 94000. yes i have also noticed a slight loss of performance. apart from this nothing else, it starts fine from cold. thankslr7pc
Answer I'd still start with the plugs, then move on to the harder stuff, while your at it check the vacuum hoses, from experience i can tell you the on e on the inlet manifold, ( up front right next to the radiator) has a habit of giving up, especially the older braided ones, newer silicon ones dont do that as much. did you have a misfire prior to this problem?? could indicate a damaged CAT converter caused by unburnt fuel passing thorough it.
Any chance you have had electronic diagnosis carried out?? if so what was the result?? any faults picked up??
