Idles high (sometimes) and two ses codes
07-04-2014, 08:03 PM
#1
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Car: 91 G92 Z28
Engine: 305 TPI
Transmission: T5
Axle/Gears: 342
Idles high (sometimes) and two ses codes
My 91 305 TPI sometimes idles too high. It's intermittent. Sometimes it's around 1k and sometimes 1600-1700. Once the engine cools down for awhile it idles fine again for awhile then the problem repeats. I pulled codes 32 and 33. EGR & MAP. EGR checks out fine and I have and extra MAP sensor that didn't solve the problem.
Poking around under the hood looking for vacuum leaks or anything blatantly obvious, I hear a sizzling coming from the the intake manifold right around the area of the alternator. I just got this car a few weeks ago and it looks like a previous owner tried to smear some RTV in the area I hear the noise. It's obvious that the intake manifold gasket is leaking here. But I would assume that my idle would be low and the engine sluggish if I was sucking air at the gasket...but in my case it's idling very high. It's a no brainer that the gasket will need replaced but could this be causing the high idle too?
Poking around under the hood looking for vacuum leaks or anything blatantly obvious, I hear a sizzling coming from the the intake manifold right around the area of the alternator. I just got this car a few weeks ago and it looks like a previous owner tried to smear some RTV in the area I hear the noise. It's obvious that the intake manifold gasket is leaking here. But I would assume that my idle would be low and the engine sluggish if I was sucking air at the gasket...but in my case it's idling very high. It's a no brainer that the gasket will need replaced but could this be causing the high idle too?
07-05-2014, 12:53 PM
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Car: 91 RS
Engine: 305
Transmission: 700r4
Axle/Gears: Stock w/ 3.73 posi
Re: Idles high (sometimes) and two ses codes
Yes! an intake leak will cause a high idle and mess with the MAP reading. Get that fixed!
07-06-2014, 09:14 PM
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Car: 91 G92 Z28
Engine: 305 TPI
Transmission: T5
Axle/Gears: 342
Re: Idles high (sometimes) and two ses codes
A good time to clean the intake, plenum and runners...followed by a coat of paint.
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