84 cross fire 4spd
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84 cross fire 4spd
what should it idle at? both cold and warmed up? and what to check since idles at 14 cold start...then at 180 degrees she drops to 800 rpm...also did jus have cat back replaced and is quieter ,,,could i need to unhook battery...tps was repalced before i bought it...still idles 800 hot 1400 -1500 cold till hits 180 temp
Last edited by pappyfreebird; Apr 21, 2008 at 10:42 AM.
Burning Brakes
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From: MD
On my 84 the "fully warm" temp was 187*. As soon as the car hit that temp my overdrive started working and the idle dropped down to where it was supposed to be. If yours does all of the above it's fine. Mine used to idle up towards 195-205 with the stock thermostat in traffic, which is plenty warm but not hurting anything. Seems to me I had the idle in mine set around 750rpms, but I messed with it so often it was always changing.
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thank you guys...seems im ok then (well my car is ),,,cause 14-1500 cold at 180 drops to 7-9 mostly 800,,,and thats when od werks too...high strung lil buggars aint they...she sure has won my heart awready... thanks again...still seems they should idle 5-600 but seems its done by sensors n ecm,,,anyway to lower it the ol fashioned way (like ear n screwdriver)
Last edited by pappyfreebird; Apr 21, 2008 at 01:22 PM.
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Spell check is your friend. The idle speed isn't as complicated as you try to make it out to be. The idle speed is programmed into the chip. It is not to be user adjusted. If you have no vacuum leaks and the TBs are synchronized, your engine should idle at 600 rpm in drive, as smooth as a fine Swiss watch. It doesn't take anything but a little good old fashioned tinkering. Don't let the electronics snow you.
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ok ive paid more attention to heat vent n defrost,, and she is non too fast at changing from vent to defrost for example,,,so any quick happind to me tips on where to stuff my paw to git er done .. thanks paps
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well closer looks at vacuem lines n i d like 5 minutes alone with the idjut that designed that mess...anyway did find a few that had been babba"d,,,n since hes my cousin i did same (used rubber line to splice the hard palstic junque ones) still idles at 8-900 but defrost n vent moves real noicely
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Burning Brakes
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From: MD
I'd give her a good old crossfire tuneup. If it idles smooth and runs strong your TB's are likely to be in good shape. The tune-up procedure I read from a mag article a while back was
Remove, Clean, and re-gasket the IAC's
Check/Adjust minimum timing
Balance the TB's
Normal SBC tuneup of plugs/wires/etc
Now, you can check your TB sync with a manometer and if they're not out of sync you don't need to adjust them. Checking them is easy, just hook up the gauge to the right ports. Adjusting them is a bit trickier, and you gotta grind off some factory welds. If you want more information about the crossfire system check out
http://crossfire.home-ip.net
I'll see if I can still find that article on the crossfire tuneup. Oh yeah, once you clean the IACs you gotta reset your battery so the car will be forced to "relearn" the settings. You might have an IAC that's sticking partly open causing your higher idle.
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From: MD
Found the article I was looking for. This one helped me a lot on my first tuneup on my '84.
http://www.corvettefever.com/techart...ing/index.html
I even re-read it just now and forgot to add something. It might be an out of adjustment TPS causing your idle issues. Altering the TPS can make the car think you're pressing the gas. While the idle may be "pre-programmed" you can trick the car into idling higher by altering the TPS. Check it out.
http://www.corvettefever.com/techart...ing/index.html
I even re-read it just now and forgot to add something. It might be an out of adjustment TPS causing your idle issues. Altering the TPS can make the car think you're pressing the gas. While the idle may be "pre-programmed" you can trick the car into idling higher by altering the TPS. Check it out.
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thanks guys ...the previous owner did put in a tps trying to lower idle...jl i dont think all the writtng was there it ended at theyll do it fer 275...im not pc savvy (kin ya tell)so if im missin something id preciate the push
hey cfi ,,, i preciate yer help also,,but air adjustment to me means on the front of carb,,,so ill have to learn what you said or where its at n what you do thanks fellas paps
i rekon i start next with the iac,,, should be one in each tbi right?? maybe plugs n wires just cause... but dont see where theyed cause high idle
hey cfi ,,, i preciate yer help also,,but air adjustment to me means on the front of carb,,,so ill have to learn what you said or where its at n what you do thanks fellas paps
i rekon i start next with the iac,,, should be one in each tbi right?? maybe plugs n wires just cause... but dont see where theyed cause high idle
Last edited by pappyfreebird; Apr 24, 2008 at 08:07 PM.
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Originally Posted by pappyfreebird
thanks guys ...the previous owner did put in a tps trying to lower idle...
Originally Posted by pappyfreebird
jl i dont think all the writtng was there it ended at theyll do it fer 275...im not pc savvy (kin ya tell)so if im missin something id preciate the push
Originally Posted by pappyfreebird
hey cfi ,,, i preciate yer help also,,but air adjustment to me means on the front of carb,,,so ill have to learn what you said or where its at n what you do thanks fellas paps
Originally Posted by pappyfreebird
i rekon i start next with the iac,,, should be one in each tbi right?? maybe plugs n wires just cause... but dont see where theyed cause high idle
Real words, proper English, capital letters and punctuation, plus better spelling, would all help to make your posts easier to read and understand, in order to provide help.
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Burning Brakes
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From: MD
Not arguing with ya CFI, just offering some clarification to my earlier suggestions. Two simple, good places to start.
Clean the IACs (read the article, it says not to get cleaner into the stepper motors) and tighten them back down. Then adjust the TPS using a multimeter. Once that is done reset the battery by disconnecting the battery for a couple minutes, and then start the car and drive it around a bit, making sure to hit atleast 45mph. Don't be surprised if it starts and runs poorly at first, it needs to relearn everything.
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i thank you jl,,,now this morning after warm up she dropped off to 7-800 n that 7 range id say would be fine...ill have a look at those iac s n the tps ...im no good at all with this new stuff...never was good but never paid anybody yet either...thats where you cats are great...thanks pappy.. i keep ya posted on what i break
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ok i tried the muti meter thing on the tps n didnt git jack ... i ran jumper wires and touched a to b with multi meter,,, switch on and only way got any reading was touching the top one and then either of the lower ones...so probably did it wrong ,,,used a sears multi meter set on vdc fer volts ...but tps was set at its lowest point so did move it around a bit ,,then ended up puttin back as was,,,havent had time to check the iacs yet..anyone want to explain (real slow ) the way to set tps ,,,thanks paps
Last edited by pappyfreebird; Apr 27, 2008 at 12:40 PM.
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