High idle after running.. Some questions - Page 2 - ZR-1 Net Registry Forums

tomtom72 · 05-03-2008

This is just a fwiw from the peanut gallery.

we have sooo many vac connections that it's a nightmare. I bought new 90 els from the I/H's, new F connector @ PCV tops, and new reg hose & MAP hose. The double connector @ the lower left TB was loose too.

I replaced what I could buy, and zip tied the TB double connector. I also did the update on the PROM from GM....net result was great for about two & a half yrs.....now the GM F connector is loose as chit again & the idle is starting to do a bit of up & down.

After all my bs, my point is even with new rubber this stuff seems to go soft in a hurry & back to square one. How to keep the rubber from softening, and or how to revive the soft rubber are the keys to all these small additive vac leaks? I clean the oil out of the PCV system on a regular basis and still it's a loosing battle.

JMHO, when people had turntables to play records......yea I'm that old!....the most common problem with all of them was a part called the Idler Wheel. A combo of rubber molded to a metal wheel. The common trick was to use iso-propyl alcohol as a reviving agent to firm up the soft rubber. We used to soak the wheels in the soloution for a day, and presto...firm rubber again. I'm gonna try it & see what happens on the old stuff, I saved all the BG/OEM parts as spares.

Sorry to be sooo long about this!

32valvZ · 05-03-2008

I realize this may not wok for the PCV boots or other parts in the PCV system. (it might though) However, when I pulled my plenum, I noticed a few loose vacume connections where the rubber boots met with the hard plastic lines. I used black silicone as a sealer and it seemes to work pretty well. I let it sit for a long time while waiting for parts to fully cure. I havent had any issues "yet".

-=Jeff=- · 05-03-2008

thanks for the tips guys.. I was thinking about it last night too.. specifically that 'F' connector for the PCV.. Since I know my 90 with NEVER be NCRS, I might find something else, at the local ACE, then use some old PCV hose from my 89 (if I still have some) and create something better. I know the PCV on my 89 would not get that loose, but there are many different factors between the 2 motors.

I also have the Latest MEMCAL Binary file to change as the PROM in the car was the older mask with the VERY high IAC count settings.. The Newer Mask will probably help too

-=Jeff=- · 05-03-2008

I Found that my PROM even though it was a 'Tuner' PROM, still used the early base BCC so I had a later BCC Bin file and changed the fan turn on and burned it to try.

Starts up at 1500 rpm and drops off quickly to around 800 I think.. hard to tell with the GM Accurate Tach

XfireZ51 · 05-03-2008

Jeff,

We should try putting a 92 stock bin on your chip and see how it works.

bldavis11 · 05-03-2008

Did you guys ever get this sorted out?

-=Jeff=- · 05-03-2008

Quote:

Originally Posted by bldavis11

Did you guys ever get this sorted out?

Yeah I think I am good.. combination of the having the early MEMCAL and the 'F' boot being loose on the PCV..

I will drive it around the block tomorrow to verify..

05-03-2008	#11
tomtom72 Join Date: Dec 2004 Location: Jacksonville, FL USA Posts: 4,645	Re: High idle after running.. Some questions This is just a fwiw from the peanut gallery. we have sooo many vac connections that it's a nightmare. I bought new 90 els from the I/H's, new F connector @ PCV tops, and new reg hose & MAP hose. The double connector @ the lower left TB was loose too. I replaced what I could buy, and zip tied the TB double connector. I also did the update on the PROM from GM....net result was great for about two & a half yrs.....now the GM F connector is loose as chit again & the idle is starting to do a bit of up & down. After all my bs, my point is even with new rubber this stuff seems to go soft in a hurry & back to square one. How to keep the rubber from softening, and or how to revive the soft rubber are the keys to all these small additive vac leaks? I clean the oil out of the PCV system on a regular basis and still it's a loosing battle. JMHO, when people had turntables to play records......yea I'm that old!....the most common problem with all of them was a part called the Idler Wheel. A combo of rubber molded to a metal wheel. The common trick was to use iso-propyl alcohol as a reviving agent to firm up the soft rubber. We used to soak the wheels in the soloution for a day, and presto...firm rubber again. I'm gonna try it & see what happens on the old stuff, I saved all the BG/OEM parts as spares. Sorry to be sooo long about this! __________________ 1990 ZR-1, Black/grey, #2233, stock. ZR-1 Net Reg Founding Member #316 & NCM member

05-03-2008	#12
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,071	Re: High idle after running.. Some questions I realize this may not wok for the PCV boots or other parts in the PCV system. (it might though) However, when I pulled my plenum, I noticed a few loose vacume connections where the rubber boots met with the hard plastic lines. I used black silicone as a sealer and it seemes to work pretty well. I let it sit for a long time while waiting for parts to fully cure. I havent had any issues "yet". __________________ [B]1990 #2815[/B] [COLOR="Red"][B]Red/Red[/B][/COLOR] Ported Plenum & IH (by Pete) Haibeck Chip Rebuilt FPR (by Phil) FIC Injectors Watson LT Headers 3" Stainless Works exhaust Lingenfelter Open Air Lid Bill B Built Transmission Shifter & C Beam Plates [FONT=Impact][COLOR=red]1992 [COLOR=black]#[/COLOR] 091[/COLOR][/FONT] [FONT=Impact][COLOR=#ff0000]Red/[COLOR=silver]Gray[/COLOR][/COLOR][/FONT] [B]SOLD[/B]

05-03-2008	#13
-=Jeff=- Join Date: Jul 2007 Location: Bartlett, IL Posts: 7,132	Re: High idle after running.. Some questions thanks for the tips guys.. I was thinking about it last night too.. specifically that 'F' connector for the PCV.. Since I know my 90 with NEVER be NCRS, I might find something else, at the local ACE, then use some old PCV hose from my 89 (if I still have some) and create something better. I know the PCV on my 89 would not get that loose, but there are many different factors between the 2 motors. I also have the Latest MEMCAL Binary file to change as the PROM in the car was the older mask with the VERY high IAC count settings.. The Newer Mask will probably help too __________________ 1990 Corvette ZR-1 #1051 Watson Headers (2" Primary) - 3" Magnaflow Bullet cats - LT4 Catback Late Model IH - Plenum Coilovers - 4.10s Custom Interior NCM Lifetime Member #978

05-03-2008	#14
-=Jeff=- Join Date: Jul 2007 Location: Bartlett, IL Posts: 7,132	Re: High idle after running.. Some questions I Found that my PROM even though it was a 'Tuner' PROM, still used the early base BCC so I had a later BCC Bin file and changed the fan turn on and burned it to try. Starts up at 1500 rpm and drops off quickly to around 800 I think.. hard to tell with the GM Accurate Tach __________________ 1990 Corvette ZR-1 #1051 Watson Headers (2" Primary) - 3" Magnaflow Bullet cats - LT4 Catback Late Model IH - Plenum Coilovers - 4.10s Custom Interior NCM Lifetime Member #978

05-03-2008	#15
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,666	Re: High idle after running.. Some questions Jeff, We should try putting a 92 stock bin on your chip and see how it works.

05-03-2008	#16
bldavis11 Join Date: Mar 2006 Location: Portsmouth, VA Posts: 245	Re: High idle after running.. Some questions Did you guys ever get this sorted out?