08-09-2014 | #1 |
Join Date: Feb 2014
Location: AZ
Posts: 860
|
Problem o' the day...
I decided to smokescreen the neighborhood today and took the car out for a drive. I started noticing a slight stumble at low RPM, so subtle that I thought I might have been imagining it. But it got progressively worse. Then, I turned it off for 5 minutes and when I restarted it, it idled up to about 2K and hung there, idling somewhat roughly. A stab at the gas did not reduce the idle. On the way home it continued to stumble badly at low RPM, and felt fine when I nailed it. I was hoping the MAP hose came off but no dice. All vacuum lines are intact, no changes there, it does not seem to me like a vacuum issue. I have not filled up recently so it's not bad gas. The plugs, coils, injectors and fuel filters have all been changed.
Any ideas? TIA! |
08-09-2014 | #2 |
Join Date: Aug 2005
Location: Scottsdale, AZ
Posts: 2,452
|
Re: Problem o' the day...
Dam you got bad luck, sounds like a vacuum leak with the idle issue
|
08-09-2014 | #3 |
Join Date: Feb 2011
Location: San Marcos CA
Posts: 1,802
|
Re: Problem o' the day...
take a look at the fuel tank purge solenoid line (under the plenum). there is a hard line that curly-q's around in a circle and attaches on the plenum corner close to the throttle body. you'll definitely get the won't-idle-below-1300 rpm from that leak.
|
08-09-2014 | #4 | |
Join Date: Feb 2014
Location: AZ
Posts: 860
|
Re: Problem o' the day...
Quote:
This car has 16K miles and has been garaged its entire life. I hardly ever drive it, yet I seem to have a major issue surfacing roughly every 5 miles of drive time. The aluminum guts of an LT5 are obviously bulletproof but everything surrounding it is clearly ludicrously delicate. Sorry if I'm offending anybody out there but I need to vent. I'm not a mechanic; I want a driver, not a project. |
|
08-09-2014 | #5 |
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,700
|
Re: Problem o' the day...
Send it to Chicago.
__________________
[SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX |
08-10-2014 | #6 | |
Join Date: Jun 2005
Location: pittsburgh
Posts: 4,632
|
Re: Problem o' the day...
Quote:
That said: I would be willing to wager that your vacuum leak is coming from the rectangular rubber block on the plenum that connects the EVAP and PCV system. The block breaks down and gets loose and causes a high idle. Mike100, on the 90, the EVAP purge is attached differently than the 91-95 cars.
__________________
It's not the car, it's the people - Doug Johnson 90 r/r "KEYS ON" nick named "T.L.B" |
|
08-10-2014 | #7 |
Join Date: Feb 2004
Location: Ma
Posts: 404
|
Re: Problem o' the day...
Chris with KOEO how often does the pump cycle?
__________________
1990 ZR1 #2574 Medium Quasar Blue Metallic 1 of 19 |
08-10-2014 | #8 | |
Join Date: Aug 2005
Location: Scottsdale, AZ
Posts: 2,452
|
Re: Problem o' the day...
Quote:
|
|
08-10-2014 | #9 |
Join Date: Feb 2014
Location: AZ
Posts: 860
|
Re: Problem o' the day...
Kevin and Phil, Bill just replaced the rubber PCV block with a new piece from Jerry. Quasar, my pump goes quiet for about 3 seconds and runs for just a moment. I think I've finally made the decision to ditch the entire secondary system.
|
08-10-2014 | #10 |
Join Date: Aug 2005
Location: Scottsdale, AZ
Posts: 2,452
|
Re: Problem o' the day...
Getting rid of system, I like it, Bill has a camera to look under plenum
|
|
|