My idle jumps a couple hundred rpm.
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Car: 1988 camaro
Engine: cammed 3.1
Transmission: 700r4
Axle/Gears: 10 bolt 3.42
My idle jumps a couple hundred rpm.
My car has never had a steady idle like if its at 900rpm it will jump between 700-900 rpm it has always had this problem but never caused any problems its just really annoying. I've replaced most of the sensors except for the TPS, oil pressure and o2 sensor. All vacuum lines, injectors etc have been replaced. Engine work starts next week but I would like to figure out the idle problem before I tear into it to put the new cam in.
Also I have to replace my rear main seal, water pump, timing cover gasket, valve stem seals and whatnot but am not sure if I should put new head gaskets in or just leave them be since they aren't leaking, I'd be kinda worried the exhaust manifold bolts will snap off..
Also I have to replace my rear main seal, water pump, timing cover gasket, valve stem seals and whatnot but am not sure if I should put new head gaskets in or just leave them be since they aren't leaking, I'd be kinda worried the exhaust manifold bolts will snap off..
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Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: My idle jumps a couple hundred rpm.
is the ac comp cycling on and off because its low/empty?
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Car: 1988 camaro
Engine: cammed 3.1
Transmission: 700r4
Axle/Gears: 10 bolt 3.42
Re: My idle jumps a couple hundred rpm.
The ac compressor is seized. The car runs amazing other than the idle issue. Maybe it just needs to be driven more being that its rarely driven since I'm working towards getting it road worthy.
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Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: My idle jumps a couple hundred rpm.
I'd put a full gasket set on the top end and then see what happens... Could be valve covers leaking or any number of things. If you're going to do the valve seals, might as well do the head gaskets at the same time and replace the seals with the heads off (much easier). If you're going to do a ton of engine work anyways, might as well do it all at the same time and make sure there's new gaskets all around. May also be bad sealing of the PCV parts (valve to cover, valve nipple to tube, tube to intake, pass side tube elbow to valve cover and tube joint at the intake bellows may be cracked).
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Car: 1988 camaro
Engine: cammed 3.1
Transmission: 700r4
Axle/Gears: 10 bolt 3.42
Re: My idle jumps a couple hundred rpm.
You were spot on with the PCV valve elbow, it wasn't in all the way pushed it in more now it idles at a steady 900rpm. I'm gonna go ahead and replace the head gaskets being pretty much all the other gaskets are being replaced. Would the cheap felpro head gasket be fine or should I look into getting the felpro severe duty gaskets? Should I do the timing chain while the cover is off? Engine has under 30k
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Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: My idle jumps a couple hundred rpm.
Get the FelPro HS8699PT2 head gaskets... I don't think you need the severe duty ones or the MLS head gaskets (that are $40 a piece). Don't get the super cheapo graphite ones either (I'll be getting a pair of those in my 3100 set and I'm going to chuck them where they belong, the trash). No, you don't need to do the timing chain... Most places recommend that at 100K.
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Car: 1988 camaro
Engine: cammed 3.1
Transmission: 700r4
Axle/Gears: 10 bolt 3.42
Re: My idle jumps a couple hundred rpm.
Those will be the ones I go with then. I'm getting a full felpro gasket set so if those aren't in there I'll just get them at the parts store and use the ones in the kit for my fiero since I have to tear into it soon due to a spun rod bearing on #4. Thanks for the help Maverick it's much appreciated
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#8
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Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: My idle jumps a couple hundred rpm.
LOL... #4 spun rod bearing... Only part I have left of my blown 2.8 is the #4 piston and 2 pieces of the rod. Spun bearing left for a while plus a 3K RPM start (don't know why it did that but it ran for 3 sec and then wouldn't turn any more due to the #4 piston so far out of the bore that the upper ring held it out) equals boom and a nice hole in both block and oil pan . That's what happens with no air dam...
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Car: 1988 camaro
Engine: cammed 3.1
Transmission: 700r4
Axle/Gears: 10 bolt 3.42
Re: My idle jumps a couple hundred rpm.
That sucks this one still isn't real bad so I should be good just getting the crank reground and a set of bearings although I've found crank kits for like 85 bucks. I saw your thread about your car and I wish you much luck on that build I may try a hybrid build once I stop being lazy and learn how to tune.
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Car: 2003 Hyundai Tiburon GT
Engine: 2.7L V6
Transmission: 6-speed
Axle/Gears: 4.41
Re: My idle jumps a couple hundred rpm.
Thanks. Engine's about halfway (debating on whether to call a machine shop or not and have the cam bearings replaced... Still don't know where those couple shavings in the pan came from, but I haven't looked over the crank bearings yet). Body is in limbo due to power problems outside (as in there is no power so I can't use my grinder to start cutting off rusty metal on the doors), and the crappy weather tied with my loss of work hours is not going well for going to the JY and getting the replacement quarter parts... It's making me .
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