Hi Idle 1K RPm

[Don in VT]

Hi,

I have found that I have developed a high idle and I was wondering if a VERY loose rubber dual PVC valve connector could be the cause of the high idle speed ( 1K RPM). The rubber connecor is sloppy loose with almost no sealing to the PCV valves.

I would guess that the connector is very hard to find so has anyone come up with an alternative (besides the oil catch can) to replacle the connector ?

Thanks,

Don in VT

[Paul Workman]

Originally Posted by Don in VT

Hi,

I have found that I have developed a high idle and I was wondering if a VERY loose rubber dual PVC valve connector could be the cause of the high idle speed ( 1K RPM). The rubber connecor is sloppy loose with almost no sealing to the PCV valves.

I would guess that the connector is very hard to find so has anyone come up with an alternative (besides the oil catch can) to replacle the connector ?

Thanks,

Don in VT

Don,

I assume we're talking about the rubber piece that holds the PVC valves themselves, and to which the hardline to the front of the plenum is attached?

Anyway, you could pull the hardline out of the rubber PVC piece and hold your thumb against the open end of the hardline and see if your idle is affected.

If that doesn't affect the idle, then pressing a hard, vinal-covered (3-ring) notebook tight across the open air horn while idling will kill the motor, UNLESS there is a vacuum "leak" somewhere. If the motor kills (try it more than once) then the problem may be with the TPS votage or crud in the TB, or IAC crudded up...for starters.

Asking a stupid question... Is the idle actually "fast", or are you only referring to the tack reading???

P.

P.

[Paul Workman]

Originally Posted by Don in VT

Hi,

I have found that I have developed a high idle and I was wondering if a VERY loose rubber dual PVC valve connector could be the cause of the high idle speed ( 1K RPM). The rubber connecor is sloppy loose with almost no sealing to the PCV valves.

I would guess that the connector is very hard to find so has anyone come up with an alternative (besides the oil catch can) to replacle the connector ?

Thanks,

Don in VT

Don,

I assume we're talking about the rubber piece that holds the PVC valves themselves, and to which the hardline to the front of the plenum is attached?

Anyway, you could pull the hardline out of the rubber PVC piece and hold your thumb against the open end of the hardline and see if your idle is affected.

If that doesn't affect the idle, then pressing a hard, vinal-covered (3-ring) notebook tight across the open air horn while idling will kill the motor, UNLESS there is a vacuum "leak" somewhere. If the motor kills (try it more than once) then the problem may be with the TPS votage or crud in the TB, or IAC crudded up...for starters.

Asking a stupid question... Is the idle actually "fast", or are you only referring to the tack reading???

P.

[XfireZ51]

Originally Posted by Don in VT

Hi,

I have found that I have developed a high idle and I was wondering if a VERY loose rubber dual PCV valve connector could be the cause of the high idle speed ( 1K RPM). The rubber connecor is sloppy loose with almost no sealing to the PCV valves.

I would guess that the connector is very hard to find so has anyone come up with an alternative (besides the oil catch can) to replacle the connector ?

Thanks,

Don in VT

Don,

Absolutely it will cause a high idle. Several ways to help seal that using zip ties and sleeving the PCVs. I also have spare PCV hoses available.
Finally, check TPS voltage and Min Air Adjustment.

[Don in VT]

Thanks everyone. All the responses were great. I will try them all.

I just put in a NOS TPS and it is set up to .54 v KOEO. Smooth idle but somewhat high. The idle is high, it is not just the tach reading.


Thanks again

Don

[XfireZ51]

Originally Posted by Don in VT

Thanks everyone. All the responses were great. I will try them all.

I just put in a NOS TPS and it is set up to .54 v KOEO. Smooth idle but somewhat high. The idle is high, it is not just the tach reading.


Thanks again

Don

Don,

You need to set the Min Air first based on the IAC counts (10-20 at no load idle), THEN adjust the TPS voltage.

[Paul Workman]

Originally Posted by XfireZ51

Don,

Absolutely it will cause a high idle. Several ways to help seal that using zip ties and sleeving the PCVs. I also have spare PVC hoses available.
Finally, check TPS voltage and Min Air Adjustment.

I agree

Purdy sheer "the Don" will need a scanner or the like to see IAC counts, in order to determine idle set screw setting. And too, if IAC counts are ZERO, then air is getting in somewhere!

Don, there should always be idle air counts; how many depends on engine temp and idle screw setting.
__
P.

[mike100]

An easy way to tighten up the PCV 'f-pipe' rubber coupler is to wrap a layer of electrical splicing tape (not regular electrical tape) to the nipples of the pcv valves themselves. As this is a thicker rubber, self sealing type of wrap, it will really grip to the original rubber grommet and won't have that barely fitting loose feel.

[tpr60]

If your car is a 1990 GM had a up dated prom for high idle and slow idle recovery, check service bulletins, I used one and it worked. There is a Registry thread about how to make the PCV valve holder out of copper fittings, I did it and it worked great at about a cost of $15 and two hours work.

[Don in VT]

Hi All,

Wow, this thread is a keeper. More great ideas and way to optimize the idle. The suggestion to make the F component out of copper tube is elegant . I can do that right away.

Thanks again

Don