Pressure testing the intake system .......Continued

Chuck Pierce cpcycle at
Sat Jul 31 11:39:28 EDT 2004

Thanks for the input Phil.
The plugs have been in for about 20k. I  like the wine cork plug that is 
easy to do. I will order some o rings on Monday for the injectors and 
while I have them out I will test them to check their operation..
In looking at the Crank case pressure valve it looks like it has a hole 
that vents to the outside, I would think that it would go to a diaphragm 
and not leak through to the crank case vent system.
The seepage on the #5 spark plug is not real major, there was no oil up 
in  the connector ( still something to watch), I did not check the plugs 
as my old school plug socket is to big to get at them( bummer I get to 
buy a new tool!).

Chuck Pierce
91 200tq 20v Avant

Phil Rose wrote:

> At 5:23 PM -0700 7/30/04, Chuck Pierce wrote:
>> Continued from earlier:
>> I fixed the hose and found that the crankcase pressure valve also 
>> leaks with the system pressurized, if I am correct that is not 
>> supposed to happen.
> I believe you are _not_ correct about that. The procedure I followed 
> was to remove the  hose ( from the forward outlet of the pressure 
> valve) and insert a plug (into the hose) during the pressure testing. 
> A wine-bottle cork fits nicely. This eliminates the leakage that can 
> occur via the crankcase breather system (dipstick, etc). Perhaps it's 
> possible to simply clamp off the hose (vise-grip?), instead of 
> inserting a plug.
>> I went out and got a barbed tubing elbow to replace the crankcase 
>> pressure valve so I could continue to look for leaks.
>> Found some air coming out from the dipstick, plugged that,
> dipstick plug is unecessary  if the crankcase breather is clamped shut 
> or disconnected as  described (above). However, in any event it's good 
> to have a tightly fitting o-ring seal for the dipstick. Even with a 
> good o-ring, the pressure testing can "blow" the dipstick unless the 
> breather is disconnected.
>> now it seems that I have some leakage around the injectors where they 
>> go into the intake manifold this is probably not a good thing.
> I would think that's correct (not a good thing).
>> I did not use more than 20psi for this testing. I did not seem to 
>> hear any leaks coming from the front end of the car( intercooler & 
>> connections). Pulled the spark plug wires out and found the #5 plug 
>> connector had some oil on the end. So this probably means the valve 
>> cover gasket is leaking ( at least the portion that seals the #5 
>> spark plug hole).
> How old are the plugs, and are they the oem specified ones??? They do 
> tend to loosen considerably over time, so I'd advise removing, 
> cleaning and re-tightening each plug.
>>  Found some seepage at the rear of the valve cover also( while I was 
>> looking around).
> Very common. Such seepage (and elsewhere) became evident within 6 
> months after I installed a brand-new gasket. Oil seepage into the 
> sparkplug ports is potentially more serious. I didn't have that problem.
>> Still do not think I have found why the car failed the smog test with 
>> really high hydrocarbons ( 193 ppm with a 120 ppm Mx  at the low 
>> speed test).
> Someone on the list was encountering the very same smog test problem, 
> not long ago.
> Phil

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