petrol smell 4.6 hse 1995

jorjio_k said:

hello gents;
i have an annoying problem with my truck.it still smells petrol after repairing a broken fuel breather pipe from the reservoir neck,it does so after driving it and not at idle.i got the code p1178 checked for its meaning but could not understand it,i cleared it with a testbook.
i checked the charcoal canister removed it and blew air inside of it no leeks in it and good as new.i removed the hose marked "tank" and smelled it there is fuel vapors in it definetly.i have no petrol leaks what so ever and almost most of the time when i open the fuek filler cap it is hissing and blowing vapors out,not sucking in.i can smell fuel vapors also even if it is closed blowing from the emergency valve which prevents the reservoir from collapsing in case of pressure buid up.
how can i check if the purge valve is operating normaly?and is this stupid code that i got related to it?
thanks

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wammers said:

Seems pretty obvious that the purge valve that allows vapour to be drawn into engine is none functional. The code will most likely be purge valve stuck shut.

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jorjio_k said:

As i remember the code said something like maximum afmr correction bank c etc...u think 2 just go ahead and replace the purge valve?i was thinking of replacing the fuel temp sensor also,is it related 2 not starting from the 1st time when truck is hot?but didn't get a code abt it.should i replace them both?

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wammers said:

Would say sorting the purge valve needs doing, either it's failed or there is a bad connection to it. Favourite for bad starting from cold is ECU water temp sensor. Fuel temp sensor tells ECU fuel viscosity and only changes delivery a small amount. ECU water temp sensor tells ECU engine temp and puts choke on for cold start, raises tick over speed and adjusts fueling to suit so if that has failed it makes a big difference.

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jorjio_k said:

thanks for ur help,u were right about fuel problem,it was the fuel regulator vacuum hose disconnected from the plenum chamber,got it fixed and no more hot start problems.put the testbook today no faults available (knock on the wood),the purge valve is pulsating and sucking the fumes,i still have a faint smell of petrol coming from the filler cap,guess purge valve isn't sucking fast enough,temperatures r reching 44 celsius alot of heat=alot of vapors i think.
thanks sir

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wammers said:

I have not been knighted yet my friend, no problem glad to have helped.

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jorjio_k said:

I can't believe it,hot start pro again even when vacuum tube connected.no faults on testbook,that leaves wht?fuel regulator?injectors cleaning?2 ways valve under filler neck?wht 2 do 1st?pro after pro in this stupid truck .thanks alot

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