What rpm should a 98 LS1 idle at?
01-12-2007, 10:22 AM
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What rpm should a 98 LS1 idle at? bone stock 98 mine is idling around 850-900 warm 1200 on cold startup. is this normal? I did seafoam my car and cleaned the TB out with no luck. Should I clean the IAC valve, not even sure if the LS1s have it or not.
01-12-2007, 12:07 PM
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Stock idle rpm for all years LS1 F-bodies is:
M6: 800rpm
A4: 650rpm (park/neutral), 550rpm (in gear)
The stock tach is off 150rpm or so, as stated above. My tach will show about 700rpm in gear idle, while my scanner shows ~550rpm.
M6: 800rpm
A4: 650rpm (park/neutral), 550rpm (in gear)
The stock tach is off 150rpm or so, as stated above. My tach will show about 700rpm in gear idle, while my scanner shows ~550rpm.
01-12-2007, 01:25 PM
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is there a adjustment screw on the LS1 to bring the idle down a bit, I feel like it is idling to high at the moment. and is there a idle air control motor on these cars?
01-12-2007, 01:40 PM
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Originally Posted by fatboyq
is there a adjustment screw on the LS1 to bring the idle down a bit, I feel like it is idling to high at the moment. and is there a idle air control motor on these cars?
01-12-2007, 06:46 PM
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Originally Posted by fatboyq
is there a adjustment screw on the LS1 to bring the idle down a bit, I feel like it is idling to high at the moment. and is there a idle air control motor on these cars?
Again, I wouldn't trust the stock tach too much. My park/neutral warm idle is about ~800ish on the tach. But in reality it scans out to be ~650 where it should be.
02-02-2007, 12:58 PM
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my car is idling too low atm... Tach shows 450 in gear. It is bad because at that speed the alternator won't recharge the battery efficiently. At a stop i have to rev to ~550 on the tach to get the battery to charge.
It sucks that you can't mechanically adjust this. Any ideas why the idle speed would drop? Don't think putting a catback on would've done that.
It sucks that you can't mechanically adjust this. Any ideas why the idle speed would drop? Don't think putting a catback on would've done that.
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02-02-2007, 01:16 PM
#8
Originally Posted by irnbru83
my car is idling too low atm... Tach shows 450 in gear. It is bad because at that speed the alternator won't recharge the battery efficiently. At a stop i have to rev to ~550 on the tach to get the battery to charge.
It sucks that you can't mechanically adjust this. Any ideas why the idle speed would drop? Don't think putting a catback on would've done that.
It sucks that you can't mechanically adjust this. Any ideas why the idle speed would drop? Don't think putting a catback on would've done that.
02-02-2007, 04:23 PM
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when i start it up it idles at 550 according to the tach and everything is fine (headlights on or off).
When it is warmed up, the idle drops to 450 and if i turn the headlights on, the battery starts to slowly die unless i rev to ~550. New (reman.) alternator and new battery in it.
When it is warmed up, the idle drops to 450 and if i turn the headlights on, the battery starts to slowly die unless i rev to ~550. New (reman.) alternator and new battery in it.
05-08-2010, 01:56 AM
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lol i was wondering the same thing but i got a lt1 m6...mine idles at 1000-950 warm but it has long tube headers, no maf and the previous owner is such a dipshit im pretty sure he didnt tune it and that would be why mine idles high i guess
09-14-2010, 08:57 PM
#14
loud vibration and low idle Stock '00 SS Auto 109,000 miles
When I first crank the car in the morning and put in gear, the idle (stock tach) shows 500 rpm. Right after I put it in gear, a loud high frequency vibration is heard from somewhere in the drive train. Don't know what this could be. Stops in about 30 seconds, but starts again when I pull up to a red light. I'm afraid something is going to go soon. Could it be a pulley? Just replaced both idler pulleys because they were squealing.
Engine is stock. Transmission was rebuilt by professional who builds GM transmissions as a specialty. New plugs and wires at 100,000 miles. Cleaned TB and have run Seafoam throught engine. Started noticing this problem before tuneup. I expected the tune up to cure it but no luck.
Any ideas? Thanks!
When I first crank the car in the morning and put in gear, the idle (stock tach) shows 500 rpm. Right after I put it in gear, a loud high frequency vibration is heard from somewhere in the drive train. Don't know what this could be. Stops in about 30 seconds, but starts again when I pull up to a red light. I'm afraid something is going to go soon. Could it be a pulley? Just replaced both idler pulleys because they were squealing.
Engine is stock. Transmission was rebuilt by professional who builds GM transmissions as a specialty. New plugs and wires at 100,000 miles. Cleaned TB and have run Seafoam throught engine. Started noticing this problem before tuneup. I expected the tune up to cure it but no luck.
Any ideas? Thanks!
