Hi all, my Z stinks of fuel but only on start up and also hesitates but when she gets warm both these problems clear. could this be due to the old rubber fuel hoses on the engine? should i get the metal pipes from smithes?

 

Regards Andy

Andy, check the connections around the fuel dampner and regulator are tight, as on start up the fuel pressure increases, only noticible when cold, as when hot, it may still be leaking but evaporates.

Also check around fuel filter.

Have had the same,

Items 28 & 29 in this pic.

 

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Hi Stu, thanks for your reply, i checked them they seem tight cant see any damp areas at the minute. Are these the only rubber pipes in the engine bay? they are metal from tank to engine arent they?

check ya temp sensor is ok aswell

Hi, changed the temp sensor and plug last year but when looking at this issue on the threads does lead to the temp sensor, will remove and check it again just incase.

maybe just clean the contacts on the connector

Have a look under the fuel pressure regulator there's a very short hidden pipe that joins it to the fuel rail that is a really common failure.

It's probably best to take it off and replace those pipes as they will be really old and perished.

If it's not that then there is a really awkward pipe that joins the 2 halves of the fuel rail under the pulley for the throttle bodies.

I seem to remember you can get to it by taking the throttles off and forcing your way in, otherwise it's a plenum off job!

Other than that it's a case of replacing the rubber pipes on top of the engine but sounds like you already checked those.

A good tip to find the leak is to put talk on all the joins when the engine is cold so when you start it up you can see the leaks even if it's evaporating.

The Smithies pipes are great and will eliminate part of the problem but I bet your leaks are under the fuel reg or throttle linkage.