Ya, that may or may not have something to do with it. It's a 4 cylinder engine, and if that's an "undamped" vacuum gauge, it might fluctuate like that and be normal. More cylinders = smoother reading (assuming the engine is ok otherwise), and a dampened vacuum gauge will smooth out the reading as well. I prefer undamped, but that's me...
Otherwise, that reading is kinda low.
Where are you at? Any idea what altitude?
What rpm is the engine running at in the video? Is the throttle closed? And by throttle, I don't mean the gas pedal, I mean the throttle plates themselves.
Engine warmed up or cold?
Do the same thing, but snap the throttle a few times, try to wind up the engine a bit.
99% of the questions that are "STRANGE" have a dirt simple answer...usually answered by a dirt simple search.
Is it just me, or does the majority overlook the obvious?
Somebody ate a whole bag of dumbass for breakfast.
Why do people continue to run a vehicle when a warning light comes on or starts flashing? Isn't that a clue that something is wrong and you probably should NOT drive it?
Is this whole car driving thing really freekin' brain surgery?
Here's something new for the crowd/clowns...
"A little bit of Google goes a long way!"
Ever notice the one post wonders for info on turbo'ing a GA16 are never heard from again after they figure out the cost???
And if you can read this, you don't need glasses! :)
The vacuum gauge reading is VERY low indicating a major vacuum leak.
Here are some vacuum gauge readings and their indications:
Low & steady - Late ign timing/valve timing, low compression
Very low - Vacuum leak
High & steady - Early ign timing
Gradual drop in reading from idle to higher RPMs - Excessive back pressure in exhaust system
Intermittent fluctuation - Ign miss, sticking valve at idle
Needle fluctuates as engine speed increases - Ign miss, blow head gasket, leaking valve or weak valve spring
did a good check over on hoses and didn't see any damaged ones, what else could cause a major vacuum leak like that? oh its about 45 degrees here, I live in middle tennessee, engine was warm and it was at idle. snapped throttle and it went to zero but wasnt an instant snap. I've watched videos about snapping the throttle and mine seemed to take just a lil longer...don't know if thats signifigant or not. took the valve cover off today cause i can hear the timing chain rattle a little bit...honestly looked to be fine on top but I did find a chewed up piece of plastic inside, so i'm assuming the bottom of it is shot.
Last edited by Stowedyco; Feb 17th, 2013 at 02:22 PM.
You could have a vacuum leak where the intake manifold bolts to the head. You can spray some soapy water around the intake manifold gasket area while the engine is idling; if it's sprayed on a leaking area, the idle will change and the vacuum gauge temporarily will show a higher vacuum.
A low vacuum reading can also be caused by late ignition timing or incorrect cam timing. Since you're getting chain rattle, the chain could have skipped a tooth.
stopped up cat was the first thing I thought of. already tried taking it off in front of the cat. The timing chain looks new, and seems to be tight on there...as I was told it did get replaced...maybe they didn't replace the guide?!? im gonna try soapy water here shortly see if I see anything. I did notice on the 4 intake ports going into the head, 2 of them are covered in oil, the other 2 are not.
I got so frustrated, and i needed to get it done quick, so I just took it to a mechanic...I explained the symptoms and problems, he said it sounded like a timing issue. He hasn't gotten back with me yet but I will let you know what it is as soon as He calls me.
i check mine but previous owner already take it out, so still have the same bogging issue. i checked the codes from ECU but the only error code was 23 (idle switch) the funny part is that the car idles fine.
well it has been rainy, cold and snowy the last couple of days so i haven't been able to really get down in it...I'm so frustrated with it right now anyways...I did take the exhaust off again before the cat...guess what!!! still boggs with gas coming out of the tb...stupid tennessee redneck mechanics...I have an extremely high idle...about 1800-2k...just will not rev down.
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.