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sinhumane
07-19-2007, 02:43 PM
ok. just bought a 95 sc 5 sp. at idle, it pulls 10 lbs vaccum... was informed by a friend, that this isnt good.... lol. newbie question... but WHY is this bad, and what causes it? could a clogged egr passage be a culprit, or maybe a vac leak?

Merlon
07-19-2007, 02:47 PM
soudns like a vac leak. have the intercooler pipes been changed recently. maybe the sc swapped out?

how much boost do you get.

some people will say spray carb cleaner around some hoses and the intercooler piping, see if that messes with the idle, then you know thats where it leaks.

or you could spray some soapy water, and look for bubbles.

MikeKanterakis
07-19-2007, 03:14 PM
could be plugged cats. what's you're idle rpm?

sinhumane
07-19-2007, 03:20 PM
i havent driven it yet admittedly... lol. 35thauto (matt) drove it home as i wass driving my gf's car back... i'll know tonight when i get back into it... matt also sprayed everyhting, and no shift in idle... could it be a disconnected vaccum line somewhere? i know there was one in particular prone to blowing off... anyone have a pic for me? also, the previous owner said the vac line for the boos gauge kept popping off, maybe i'm just getting a faulty reading? is 10 lbs high or low?

MakoSC
07-19-2007, 03:25 PM
i havent driven it yet admittedly... lol. 35thauto (matt) drove it home as i wass driving my gf's car back... i'll know tonight when i get back into it... matt also sprayed everyhting, and no shift in idle... could it be a disconnected vaccum line somewhere? i know there was one in particular prone to blowing off... anyone have a pic for me? also, the previous owner said the vac line for the boos gauge kept popping off, maybe i'm just getting a faulty reading? is 10 lbs high or low?

5-speed should pull more vac at idle than an auto
the only "other" reason I know is a cam
I only pull about 10 at Idle (with cam)

sinhumane
07-19-2007, 03:32 PM
could a clogged egr passage be a likely culprit? :confused:

David Neibert
07-19-2007, 04:36 PM
could a clogged egr passage be a likely culprit? :confused:

On a stock cam SC the normal vacuum at idle is around 20 inches....so I'm guessing the hose going to the boost gauge is leaking if your only showing 10. If it was really leaking that bad, it wouldn't even idle.

David

sinhumane
07-19-2007, 04:54 PM
yeah. the thing idled fine... cant remember where the rpms were.. guess i'll try and figure out a way to get that fixed.. 'least its nothing major...

now, anyone have any clue about why the lights flutter (inside and out) whe its running? alternator maybe? would an alt from a 95 3.8 lx fit? (only because the one on it is new)

David Neibert
07-19-2007, 05:00 PM
yeah. the thing idled fine... cant remember where the rpms were.. guess i'll try and figure out a way to get that fixed.. 'least its nothing major...

now, anyone have any clue about why the lights flutter (inside and out) whe its running? alternator maybe? would an alt from a 95 3.8 lx fit? (only because the one on it is new)

Probably needs a new headlight switch. I don't think the 3.8 lx alt would fit anyway.

David

sinhumane
07-19-2007, 05:16 PM
well, it could be the headlight switch, but all the lights on and in the car flutter. overheads, tails, gauges, etc.

91 XR7
07-19-2007, 09:23 PM
Alternator or Voltage regulator... I'm leaning towards Alternator..

Also if you have access to a Vaccum guage, i would grab it (or buy one) and tape into where the Factory boost guage is, or another location and be shure about the Vaccum..

after all Factory guages SUCK! :p

sinhumane
07-19-2007, 09:42 PM
like dave said tho... if it was only pullin 10 lbs, it would be sputtering and die.. and i was thinkin alternator too..

rzibilske77
07-19-2007, 09:48 PM
now sure about the 5 spd, with my 95 auto while in park/idle i have about 18lbs vac.
Now when dropped in gear it levels off about 11-12.........but idles smooth 500-700 rpm.
not cam'd that i know of:eek:

speedracer6
07-19-2007, 11:34 PM
Could be an alternator bearing seizing up. This would also explain the huge load that is causing your 10 lbs at idle.

Tickler
07-20-2007, 03:36 PM
Either way, you should take your alternator into autozone or some place and get it tested.

sinhumane
07-20-2007, 07:22 PM
yeah, 5-700 is where its idling in 1st.

sinhumane
07-21-2007, 10:54 PM
alrighty... got that fixed... lol. it was a rotted out vac line for the boost gauge... god, it was priceless to see the look on the faces of the autozone guys when i told them what the vac line i bought was for. one of them actually challenged me.. he jut bought an impreza wrx (non sti) 230 hp, about 240-250 ft lbs i would imagine... i told him the ungodly torque numbers sc's put down and he shut up reeeeal quick. :D but i got my nylon tubing, replaced it all, and i'm pulling down 20 lbs... now.. why do the rpms drop so much when the ac is on? i'm thinking this alternator or the a/c compressor is being stingy with power.

MikeKanterakis
07-22-2007, 08:39 PM
You probably need a new Idle Air Control Vavle. It's on the throttle body next to the Throttle Position Sensor.

sinhumane
07-23-2007, 12:28 AM
it is new... it only bogged down once though... doesnt any more.