why my Z overfuels,

I start the car, put her in gear almost instantly, drive a few yards, switch her off and then the next time she wont start untill I crank her for 5 mins and all the smoke puffs out the back.

Only does this when engine is cold and switched off befor it gets warm, when I leave it to warm up for 5 mins and do the same as above, it's fine.

Hi ...

 

Wot fuel r u using? R u using fuel additive? Is there any pinking from the engine in any shape or form?? :headvswal

I use tesco 99 ron and apart from the engine under performing, it seems to be running fine.

could be caused by a faulty temp. sensor

could be caused by a faulty temp. sensor

 

Blazt diagnostic shows no error codes IF that would show on it.

When you start the car from cold, it uses a much-richer fuel mixture (the modern equivelent of a choke). If you turn the car off shortly afterwards, some of the extra fuel remains in the pistons. Subsequent cold starts can result in significant overfuellling and hence the engine won't start.

 

This happens on almost all vehicles in certain circumstances. Honest John is always writing about it in the Telegraph (which we get at work BTW).

 

Ian A.

Quote:

Originally Posted by lymon

could be caused by a faulty temp. sensor

 

 

Blazt diagnostic shows no error codes IF that would show on it.

 

Just fit a new one anyway. they are not expensive and this is one of the main sensors that sends "rich mixture" messages to the ECU. Make sure the terminals on the loom are not corroded also.

Are you using a standard unmodified ECU???

My Central 20 ecu can be a bit of a bu**er at overfuelling if I dont take care on starting.

HTH

yea i have a jwt chipped ecu, not too bad with starting but looking out the back and smelling its pretty obvious its overfueling

Check your compression figures when cold and if low compare with figures when warm.

 

Jeff TT