vacuum lines

terribleonexx88 · 03-13-2007, 05:51 PM

these two lines coming off this are vacuum where do they hook up to? would these snipped vac lines cause hesitation?

soocutlass · 03-13-2007, 06:38 PM

these are not necassry to hook up. How it is used is when the temp of the motor goes up it allows for your vacuum advance to work, if the motor is not up to temp the ignition timing vacuum advance will not work. So it act as a vacuum switch based on temperature to open.

soocutlass · 03-13-2007, 06:41 PM

originally it look like to switch that is mounted in the intake not the air breather sorry.

terribleonexx88 · 03-13-2007, 07:53 PM

well the two rubber lines are snipped off and i can feel the vacuum so they were hooked up to something and i cant find what. im trying to figure out why my car hesitates from a stop and i notice those lines 2day and was wondering if that had any thing to do with it

Oldsguy · 03-14-2007, 04:57 AM

If you have a vacumm leak because those lines are snipped off and not plugged that could cause your hesitation. I would plug the one from the vacumm source and find out where the other one goes and remove it. It seems that only one should have vacumm on it. Seems like what soocutlass said is right except it works on inlet air temperature instead of engine temperature. I suppose the best thing to do if your car is still completely stock is to replace the hoses onto the device and let it be. Your car is an '88 Cutlass right? There was lots of computer interaction with the engine timing by that time and unless you remove the whole thing and re-tune your engine to run without it you might be better off just to leave it all on.

terribleonexx88 · 03-14-2007, 12:58 PM

its a 78 cutlass

soocutlass · 03-14-2007, 02:59 PM

I would cap off both side of the sensor because if it is a temp switch which it looks like then it will open after it reach temp and the idle problem will come back.

Jim's rare 80 · 03-15-2007, 02:26 AM

Hi. I have an 80 Cutlass. The good is.. it's in pieces, being restored, and will be like new soon. The bad is.. It's in pieces, being restored, and I can't drive it right now. The other good is, I know this is a thermal switch to control the secondary choke pull off. It's fed off of your breather vacumn supply. If this is leaking air, it will cause hesitation, if you have a 4bbl carb, don't bypass it. Let us know engine and carb config', and we'll go from there. Jim

terribleonexx88 · 03-16-2007, 12:00 PM

its a 2bbl. does any one have pictures of there 260 2bbl i can look at because the vacuum diagram i looked at didnt help me. i took off the thermal thing altogether and it still hesitates. to get going i have to tap the gas and let off repetedly.

03-14-2007, 04:57 AM	#5 (permalink)
Oldsguy Administrator Join Date: May 2004 Location: Lees Summit MO Posts: 3,167	If you have a vacumm leak because those lines are snipped off and not plugged that could cause your hesitation. I would plug the one from the vacumm source and find out where the other one goes and remove it. It seems that only one should have vacumm on it. Seems like what soocutlass said is right except it works on inlet air temperature instead of engine temperature. I suppose the best thing to do if your car is still completely stock is to replace the hoses onto the device and let it be. Your car is an '88 Cutlass right? There was lots of computer interaction with the engine timing by that time and unless you remove the whole thing and re-tune your engine to run without it you might be better off just to leave it all on. __________________ Dan '77 Cutlass Supreme '46 2 door

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03-13-2007, 06:38 PM	#2 (permalink)
soocutlass Junior Member Join Date: Mar 2007 Posts: 15	these are not necassry to hook up. How it is used is when the temp of the motor goes up it allows for your vacuum advance to work, if the motor is not up to temp the ignition timing vacuum advance will not work. So it act as a vacuum switch based on temperature to open.

03-13-2007, 06:41 PM	#3 (permalink)
soocutlass Junior Member Join Date: Mar 2007 Posts: 15	originally it look like to switch that is mounted in the intake not the air breather sorry.

03-13-2007, 07:53 PM	#4 (permalink)
terribleonexx88 Junior Member Join Date: Mar 2007 Posts: 15	well the two rubber lines are snipped off and i can feel the vacuum so they were hooked up to something and i cant find what. im trying to figure out why my car hesitates from a stop and i notice those lines 2day and was wondering if that had any thing to do with it

03-14-2007, 12:58 PM	#6 (permalink)
terribleonexx88 Junior Member Join Date: Mar 2007 Posts: 15	its a 78 cutlass

03-14-2007, 02:59 PM	#7 (permalink)
soocutlass Junior Member Join Date: Mar 2007 Posts: 15	I would cap off both side of the sensor because if it is a temp switch which it looks like then it will open after it reach temp and the idle problem will come back.

03-16-2007, 12:00 PM	#9 (permalink)
terribleonexx88 Junior Member Join Date: Mar 2007 Posts: 15	its a 2bbl. does any one have pictures of there 260 2bbl i can look at because the vacuum diagram i looked at didnt help me. i took off the thermal thing altogether and it still hesitates. to get going i have to tap the gas and let off repetedly.