Leak-down test...Analysis? - ZR-1 Net Registry Forums

Paul Workman · 12-20-2007

To eliminate a possible leaking injector for my intermittent slightly rough idle, I took y'alls suggestion and bought a decent pressure gauge and did a leak-down test.

At idle the pressure was steady at 43#. I shut off the ignition, and after 20 minutes, it had leaked down by only 2#. I concluded the injectors are at least not leaking.

I'll "ohm" them out, soon as I can find my danged VOM...It's brand new too, and it seems to be avoiding my search, apparently. If they check out, then I will assume the injectors are prolly fine...for now.

If it isn't an injector, I'll prolly just conclude I have a lifter that wants to stick a bit after quite a bit of down time. When I fired it up to do the leak-down test, the car had been sitting for a couple weeks - some of that time in single digit temps. But, there was NO ticking sound as sometimes is the case - coupled with rough idle, rather, the idle was smooth as silk.

Mebby I'll fire it up in total darkness and see if that ticking I sometimes hear is actually a leaking sparkplug wire arching...

??

In any case, I still have butterflies in my stomach over having a Z in the garage! It is my wildest dream come true and I can't get over it! Woo Hoo!!

P.

12-20-2007	#1
Paul Workman Join Date: Nov 2007 Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri Posts: 6,493	Leak-down test...Analysis? To eliminate a possible leaking injector for my intermittent slightly rough idle, I took y'alls suggestion and bought a decent pressure gauge and did a leak-down test. At idle the pressure was steady at 43#. I shut off the ignition, and after 20 minutes, it had leaked down by only 2#. I concluded the injectors are at least not leaking. I'll "ohm" them out, soon as I can find my danged VOM...It's brand new too, and it seems to be avoiding my search, apparently. If they check out, then I will assume the injectors are prolly fine...for now. If it isn't an injector, I'll prolly just conclude I have a lifter that wants to stick a bit after quite a bit of down time. When I fired it up to do the leak-down test, the car had been sitting for a couple weeks - some of that time in single digit temps. But, there was NO ticking sound as sometimes is the case - coupled with rough idle, rather, the idle was smooth as silk. Mebby I'll fire it up in total darkness and see if that ticking I sometimes hear is actually a leaking sparkplug wire arching...?? In any case, I still have butterflies in my stomach over having a Z in the garage! It is my wildest dream come true and I can't get over it! Woo Hoo!! P.