Idle speeds vary from car to car, but for a passenger car, typical idle speeds are between 500 and 900 rpm. This idle speed also depends on the accessories that are currently running as a car's idle control system will automatically raise the idle in order to provide power for auxiliaries such as air conditioning and power steering. Keep Learning. Nov 08, 2009 Answers. With a cam the idle usually needs to be higher on auto. Usually run my idle on 350 at 700 RPM and up. I like to set it as low as possible with engine still running smoothly. On auto trans without stall speed sometimes the idle has to be 1000 or higher to keep engine running when put in gear. Hope this helps.
My Gen 2 Idles anywhere from 960-1250. Is this knock coming from a cold start? During cold start the engine runs a different valve timing to facilitate faster warmup. Did you buy gas at somewhere other than your usual place?
Cheap gas can have water or other impurities that can cause an engine knock. This can be alleviated with an octane boost and a refill with higher quality gas. Have you tried replacing your spark plugs yet? Spark plugs and wires replacement is usually a cheap and good place to start when troubleshooting detonation issues. My Gen 2 Idles anywhere from 960-1250.
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Is this knock coming from a cold start? During cold start the engine runs a different valve timing to facilitate faster warmup. Did you buy gas at somewhere other than your usual place?
Cheap gas can have water or other impurities that can cause an engine knock. This can be alleviated with an octane boost and a refill with higher quality gas. Have you tried replacing your spark plugs yet?
Spark plugs and wires replacement is usually a cheap and good place to start when troubleshooting detonation issues. Click to expand.I would say buy a bottle of octane boost from Napa and throw that in and then top off with fuel from chevron or another decent quality provider. If that fails look to the ignition system.
Pull your plugs and look for scorching or buildup and then test the plug gap and make sure it is around.043' with the spark plug gauge you can pickup while you're at Napa. If your Prius is over 100k and you haven't replaced spark plugs and leads then its probably about time to do it, also look into replacing PCV valve while you have it open just to save some future time and it only costs a few bucks. I would say buy a bottle of octane boost from Napa and throw that in and then top off with fuel from chevron or another decent quality provider. If that fails look to the ignition system. Pull your plugs and look for scorching or buildup and then test the plug gap and make sure it is around.043' with the spark plug gauge you can pickup while you're at Napa. If your Prius is over 100k and you haven't replaced spark plugs and leads then its probably about time to do it, also look into replacing PCV valve while you have it open just to save some future time and it only costs a few bucks.
I would still at least pull your plugs and make a visual inspection. If it hasn't thrown a CEL it could be a number of things. I've seen cracked engine mounts cause the knock sensor to retard the timing and cause early detonations when idling due to the lower RPM and higher vibration in other cars.
Do you have a video of your engine knocking? Have you considered replacing the knock sensor?
If you're burning oil I wouldn't be surprised if you have carbon deposits on the head decreasing the space in the cylinder and causing early detonation. I would still try higher octane gas or an octane booster and see if the problem follows. It would at least rule that out.
I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it.The emissions control label on the front of the engine compartment isfor the original engine (a 4.3L V6) and says I should set the fast idlespeed to 2200 RPM and the idle speed to 500 RPM. Does anyone have anidea if these numbers are good to use for setting the idle speed on myV8 as well?The truck has A/C, automatic transmission, I've got the spark plugsgapped to.045, and the ignition timing is set to 8. RochesterQuadrajet M4ME Carburetor (17085210).Anyone know the proper idle speed specifications for this type ofengine?Thanks,austin› See More. Don't know if this really matters, but a minor correction needs to bemade: the timing is set to 6 BTDC, not 8.austin wrote: I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it. The emissions control label on the front of the engine compartment is for the original engine (a 4.3L V6) and says I should set the fast idle speed to 2200 RPM and the idle speed to 500 RPM.
Does anyone have an idea if these numbers are good to use for setting the idle speed on my V8 as well? The truck has A/C, automatic transmission, I've got the spark plugs gapped to.045, and the ignition timing is set to 8. Rochester Quadrajet M4ME Carburetor (17085210).
Anyone know the proper idle speed specifications for this type of engine? Thanks, austin. 'austin' wrote in [email protected] oups.com.
I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it. The emissions control label on the front of the engine compartment is for the original engine (a 4.3L V6) and says I should set the fast idle speed to 2200 RPM and the idle speed to 500 RPM. Does anyone have an idea if these numbers are good to use for setting the idle speed on my V8 as well?
The truck has A/C, automatic transmission, I've got the spark plugs gapped to.045, and the ignition timing is set to 8. Rochester Quadrajet M4ME Carburetor (17085210). Anyone know the proper idle speed specifications for this type of engine? Thanks, austinGap sounds right, idle speed hot in gear 600 rpm, 800-900 rpm cold in gear.What year engine, and is it all original ie correct distributor for the yearof the engine?Whitelightning. Thanks for the post, Whitelightning. It's an older engine (I would sayroughtly the same year as the truck-mid-80s) that had a couple missesin it when I bought it.
I had it rebuilt a year ago. The distributormatches and they work well together. Sorry I can't be more specificabout the year. I've looked all over the engine for the VIN number(down by oil filter and along the engine case pad especially) and can'tfind it.AustinWhitelightning wrote: 'austin' wrote in message [email protected] oups.com. I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it. The emissions control label on the front of the engine compartment is for the original engine (a 4.3L V6) and says I should set the fast idle speed to 2200 RPM and the idle speed to 500 RPM. Does anyone have an idea if these numbers are good to use for setting the idle speed on my V8 as well?
The truck has A/C, automatic transmission, I've got the spark plugs gapped to.045, and the ignition timing is set to 8. Rochester Quadrajet M4ME Carburetor (17085210).
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Anyone know the proper idle speed specifications for this type of engine? Thanksaustin Gap sounds right, idle speed hot in gear 600 rpm, 800-900 rpm cold in gear. What year engine, and is it all original ie correct distributor for the year of the engine?
Whitelightning. Yeah, I should have mentioned about the original numbers: the emissioncontrol label says the fast idle 2200 RPM number should be set in Parkor Neutral, and the 500 RPM idle speed set in Drive. The truck is duefor a TX emissions inspection soon, so I might retard the timing somebefore I take it in.
I think specifications say it should be set at 8BTDC (4 on the timing indicator), right?austinaustin wrote: Thanks for the post, Whitelightning. It's an older engine (I would say roughtly the same year as the truck-mid-80s) that had a couple misses in it when I bought it. I had it rebuilt a year ago. The distributor matches and they work well together. Sorry I can't be more specific about the year.
I've looked all over the engine for the VIN number (down by oil filter and along the engine case pad especially) and can't find it. Austin Whitelightning wrote: 'austin' wrote in message [email protected] oups.com. I have an '86 GMC 1/2 ton pick-up that now has a 5.7L 350 V8 in it. The emissions control label on the front of the engine compartment is for the original engine (a 4.3L V6) and says I should set the fast idle speed to 2200 RPM and the idle speed to 500 RPM.
Does anyone have an idea if these numbers are good to use for setting the idle speed on my V8 as well? The truck has A/C, automatic transmission, I've got the spark plugs gapped to.045, and the ignition timing is set to 8. Rochester Quadrajet M4ME Carburetor (17085210). Anyone know the proper idle speed specifications for this type of engine? Thanksaustin Gap sounds right, idle speed hot in gear 600 rpm, 800-900 rpm cold in gear.
What year engine, and is it all original ie correct distributor for the year of the engine? Whitelightning.
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