Just got done adjusting the valves after a ZZ-9 install. The car idles rough when I first start it and the engine is cold. After a few minutes of warming up the car idles fine, just a little lumpy for the ZZ-9. After a while of driving the car runs beautifully. When the car gets to operating temperature it is fine. I have noticed that the rough idles get better and better after I drive the car some more. Does this mean that I need more PROM work now? I have no SES light. Or does it mean that I just have to drive the car some more so that the computer adjusts?? I have driven the car for about 3 days now and the rough idle on cold starts is improving. The battery has been disconnected for a month during the install.

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1988 GTA 5.7L Auto
355 ci. block, SLP Cold Air Intake w/ K&N, fully modified MAF Sensor, TPIS 52mm Throttle Body w/Air Foil, Throttle Body Bypass Hose, Fully Ported and Polished Plenum, Nikel-plated Ported SLP Siamesed Runners, Ported TPIS Big Mouth Intake Manifold, stock heads w/ 1.52 Comp Cams Self-aligning Roller Rockers, TPIS ZZ-9 Roller Camshaft, TPIS Valve Springs, Cloyes True Double Roller Timing Chain, TPIS Adjustable Fuel Pressure Regulator, Balanced Bosch 22 lb/hr Fuel Injectors, MSD 6AL, Taylor 10mm Wires, Bosch Platinum +4 Spark Plugs, MSD Blaster Coil, March Underdrive Pulleys, 6 3/4" Vibratech Streetdamper, TPIS Level 3 PROM, 160 T-stat, Low Temp. Fan Switch, Stock Distributor w/ Bronze Gear, SLP 1 3/4" Headers, Random Technologies High Flow Cat., Adjustable Borla Cat Back Exhaust, Level 10 PTS-3 700R4 Trans, B&M Holeshot 2400 Stall Converter, B&M Trans Cooler, TCI Aluminum Finned Trans Pan, Torque Converter Lock Up Switch, 3" Balanced Aluminum Driveshaft, 3.73 Richmond Gears, Auburn Pro-Series Differential, LPE Aluminum Differential Cover w/ Main Cap Preloads, BF Goodrich Drag Radials, Hotchkis Lower Control Arms, Hotchkis Panhard Rod, Hotchkis Tie Rod Adjuster Sleeves, Bilstein Heavy Duty Shocks and Struts, 1LE Springs, Energy Suspension Polyeurethane Bushings, Global West Tubular Subframe Connectors, Global West Steering Box Brace, HP Motorsports 3 Point Strut Tower Brace

"Why ride a stang when birds can fly?"

http://www.geocities.com/thegta

 

It might just be the cold weather. When I start my car in the morning it idles a little rough for a while and then when it warms up it idles fine.

 

It could be the cold weather, but I had this car indoors in a heated shop, and it's still the same.

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1988 GTA 5.7L Auto
355 ci. block, SLP Cold Air Intake w/ K&N, fully modified MAF Sensor, TPIS 52mm Throttle Body w/Air Foil, Throttle Body Bypass Hose, Fully Ported and Polished Plenum, Nikel-plated Ported SLP Siamesed Runners, Ported TPIS Big Mouth Intake Manifold, stock heads w/ 1.52 Comp Cams Self-aligning Roller Rockers, TPIS ZZ-9 Roller Camshaft, TPIS Valve Springs, Cloyes True Double Roller Timing Chain, TPIS Adjustable Fuel Pressure Regulator, Balanced Bosch 22 lb/hr Fuel Injectors, MSD 6AL, Taylor 10mm Wires, Bosch Platinum +4 Spark Plugs, MSD Blaster Coil, March Underdrive Pulleys, 6 3/4" Vibratech Streetdamper, TPIS Level 3 PROM, 160 T-stat, Low Temp. Fan Switch, Stock Distributor w/ Bronze Gear, SLP 1 3/4" Headers, Random Technologies High Flow Cat., Adjustable Borla Cat Back Exhaust, Level 10 PTS-3 700R4 Trans, B&M Holeshot 2400 Stall Converter, B&M Trans Cooler, TCI Aluminum Finned Trans Pan, Torque Converter Lock Up Switch, 3" Balanced Aluminum Driveshaft, 3.73 Richmond Gears, Auburn Pro-Series Differential, LPE Aluminum Differential Cover w/ Main Cap Preloads, BF Goodrich Drag Radials, Hotchkis Lower Control Arms, Hotchkis Panhard Rod, Hotchkis Tie Rod Adjuster Sleeves, Bilstein Heavy Duty Shocks and Struts, 1LE Springs, Energy Suspension Polyeurethane Bushings, Global West Tubular Subframe Connectors, Global West Steering Box Brace, HP Motorsports 3 Point Strut Tower Brace

"Why ride a stang when birds can fly?"

http://www.geocities.com/thegta

 

your lucky. my idle is rough all the time. the only internal engine thing i did was roller rockers

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RED82TA5.7L

1982 Pontiac Trans Am
Cross-Fire Injected 5.7l V8
Eldebrock Headers, 3" Hooker Cat-Back, duel outlet with quad tips.
Mods: 1.6 Proform Roller Rockers, electric fan, Corvette 5.7L computer chip, K&Ns.
Audio: JVC Kameleon CD deck, Jenson 4x6 front, Eclipes 6x9 rear, 2 10" mTx T4000 powered by a mTx 200watt amp.

[This message has been edited by RED82TA5.7L (edited December 21, 2000).]

 

Joseph,
I have the ZZ9 cam too but not as many, you have ALOT, mods as you. Also you have a 355ci too and I only have a 350ci. But I do have a TPIS LEVEL 5 chip compared to your LEVEL 3 chip. Now about startup in the cold, and I live close to you so it is simular temperatures, but my car doesn't idle rough at startup it idles at around 1300 rpms till it gets warm, about 2 minutes, and then drops to 750 rpms and then alittle lumpy cause of the ZZ9 cam.
I did have a bad ignition module that caused a bad idle at startup and then and unstable idle when it was warm but that was the only problem I had.
I would think, IMHO, that to get the most of your mods you need to upgrade your chip.

Good Luck!

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89 IROC 350 Auto
Custom DUAL Exhaust
Edelbrock Performer 6085 Aluminum Heads
ZZ9 Cam
TPIS Level 5 Chip
14.01 @ 97.0mph with 2.77's gears and a bad ignition control module!
And Free mods.

 

It's probably loading up with the extra cold start fuel. Try a lower fuel pressure this will adjust mixture while in open loop cold start.

 

For smoother operation when the engine is cold you will need to get your chip custom calibrated. I run an aftermarket cam myself and with the stock chip the car barely idles when it's cold and it buckles and hesitates a lot when driven. After a couple minutes when the closed loop kicks in it runs fine. What I did is burn me a chip that changes the open loop AFR ratio and gave it a little more gas. It idles just fine and drives a lot better when cold. So it's not the weather or anything else.. it's the ECM and the fact that it has preprogrammed tables for open loop operation. When in closed loop the ECM can adjust (somewhat) to the new cam, but in open loop its "hands" are tied. Hehe

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92 Z28 L98 350
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Ported stock heads, XR270HR-10 cam, TES headers, Crane AFPR, Flowmaster catback, MSD ignition components.
Best ET 13.5@105 mph
"Take that auto, drop it in first, hold the brakes, stomp the gas and grin from ear to ear! :-)
Click here to see my car at Truspeed.org

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