Purge Valve exonerated.

[a2jack]

Back from our 20k service with directed emphasis on the purge valve.

The purge valve is located within easy reach on the right, forward top of engine. The power connector is on top. You can put your hand right on the valve and feel it click. (Photos soon.) Or a piece of PVC pipe will allow you hear it turning on and off.

The strange tap-tap at idle is NOT coming from this valve. It seems to coming from another source yet to be determined by Smart HQ service. More later. A2Jack.

[chieftmc]

Thanks for the info. Look forward to your updates

[eqwalker]

Let's get a guess going on what the tap-tap turns out to be......I'll go first. I'm going to guess and say the.....ah........fuel pump. Reason I say that is because my parents have an 81 Honda Civic that has an electric fuel pump that makes a tapping noise as it moves the diaphragm back and forth to keep the fuel at a certain pressure and this tapping noise on it slows down when the car is idling since it is not requiring as much fuel. I know this is probably not what it really is on the smart but it is what it reminds me of.

[rfernatt]

Originally Posted by eqwalker

...and this tapping noise on it slows down when the car is idling since it is not requiring as much fuel.

I've noticed that the tapping noise is related to engine speed, on my car anyway. It is quickly drowned out by engine/road noise, but when sitting still in neutral in a quiet environment with everything off and gently revving the engine, you can hear the tapping sound speed up and slow down. It's weird that it doesn't do it consistently. Sometimes the noise is barely noticeable or seemingly absent, other times it is a woodpecker going to town behind the seats!

[a2jack]

First pix of purge valve that appears NOT to be the tap, tap source. Smart HQ service manager is waiting to confer with a tech due to return from France next week.

[jetfuel]

...hey jack....whatdahell is all over your engine.....got a car wash nearby...lol

jetfuel

[mfoster]

That doesn't look like a 451 engine.

[a2jack]

Jetfuel. Yeah! what a mess they left me at smart service. It seems they couldn't get the oil in the hole without spilling it down the side.

And yes I agree, It needs it's 20k engine clean. A2Jack

[PeteInLongBeach]

Originally Posted by a2jack

First pix of purge valve that appears NOT to be the tap, tap source. Smart HQ service manager is waiting to confer with a tech due to return from France next week.

Pic of same purge valve that DOES appear to be the tap tap source:

Tat, Tat. Tat, Now Repaired.

[andrewd]

the tat tat tat noise you refer to, couldnt the fact the engine has a timing chain not belt, and the fact you almost sit on it and there is no sound proofing contribute...

also the unusual lifter setup on the smart, makes more noise... also the fuel injectors contribute to the ticking at idle...

but without hearing the ticking noise i couldnt say.... unless its the same exactly as the turbo model... mine sounds like a diesel LOL