rough idle

Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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adams11
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rough idle

Post by adams11 »

I have a 1996 bonneville se with a 3.8. I have already taken out the MAF and cleaned it but that still hasnt worked. Also just replaced with a new alternator. Slight belt squeekage but after a while the rough idle will quit and runs fine.
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J Wikoff
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Re: rough idle

Post by J Wikoff »

When was the last time it had new plugs and wires? It smoothing out after a bit might be a clue to something, but I can't remember exactly what.
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WHITE WHINE - 1992 SSE Supercharged 236.26 ci (.040 Over) 15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers & a 10" Alpine Type R Sub, all the watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, Ceramic Coated Ported Exhaust Manifolds, Fan Override, Monroe Reflex struts, red calipers
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser, 3.45 diff and various Camaro suspension bits, LED Taillights
Dopey85
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Re: rough idle

Post by Dopey85 »

I'd say plugs, wires, and possibly check for a bad coil.
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adams11
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Year and Trim: 1996 all stock besides a system

Re: rough idle

Post by adams11 »

i just changed the plugs and plug wires probably about 2 months ago
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Re: rough idle

Post by 00Beast »

Have you checked and cleaned the IAC motor and its bore in the TB? It's the round plastic thing on the top of the TB that goes in sideways.
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adams11
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Year and Trim: 1996 all stock besides a system

Re: rough idle

Post by adams11 »

i just got the code number its p0102 MAF or VAF circuit low imput
Dopey85
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Re: rough idle

Post by Dopey85 »

double check and make sure the connectors is fully seated. If that doesn't work inspect the wires, connectors, and pins real good and make sure there aren't any cracks, corrosion, or chaffing. And if that doesn't fix the problem get a multimeter and/or test light check if there is or how much output is coming out of the connectors.
Last edited by Dopey85 on Wed Jun 16, 2010 6:42 pm, edited 1 time in total.
*~Ryan~*
2005 Suzuki Forenza, Black
1992 Bonneville SSEi, White (GONE)
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J Wikoff
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Re: rough idle

Post by J Wikoff »

Take out the MAF, and carefully clean the elements with rubbing alchohol on a q-tip.
Image
WHITE WHINE - 1992 SSE Supercharged 236.26 ci (.040 Over) 15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers & a 10" Alpine Type R Sub, all the watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, Ceramic Coated Ported Exhaust Manifolds, Fan Override, Monroe Reflex struts, red calipers
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser, 3.45 diff and various Camaro suspension bits, LED Taillights
00Beast
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Re: rough idle

Post by 00Beast »

Does the rough idle stop when the MAF is unplugged?
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Sirius wrote:Think about it. You’re tooling down the road in your Prius, knowing full-well that this thing being green is as big a sham as federally mandated ethanol-enriched gas, Russia pulling out of Ukraine, and Obamacare.
adams11
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Joined: Tue Jun 08, 2010 11:50 pm
Year and Trim: 1996 all stock besides a system

Re: rough idle

Post by adams11 »

I've taken out the MAF and used some MAF cleaner on it. It was pretty dirty. And i have not yet tried to unplug it to see how it runs without it
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Re: rough idle

Post by 00Beast »

When it's doing its rough idle, unplug the MAF sensor and see how it changes.
Bye Bye:
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RIP sandrock
Sirius wrote:Think about it. You’re tooling down the road in your Prius, knowing full-well that this thing being green is as big a sham as federally mandated ethanol-enriched gas, Russia pulling out of Ukraine, and Obamacare.
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