hinking about using a 1G FIAV Blockoff Plate and wanted to know how bad would it be if i did not run a isc motor. I am running a aem ems. The car has no A/C. Still has p/s.
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boostedinaz
Well-known member
Shouldn't be bad at all. The ony thing that will lower thr idle will be the draw of the head light, fans kickng on, and little things like that. Those will only drop the idle a few RPM. I would just raise it to say 950 or more so when those items do drop it a bit the car won't vibrate.
not bad at all. i got no a/c, no abs, with 65 watt headlights bulbs, battery in the trunk, no cruise control, and im moving towards electrical power steering. it still idles fine after a minute of warm up with my foot on the pedal hanging at 1500 rpms.
I have heard of people in cold climates (like NJ) having warm up/idle trouble in winter. But others say they didn't have trouble, so it may be a little different for each car (you know how these cars are.) I blocked my FIAV when I lived in Ohio but kept the ISC functional. Had no problems in cold weather. If your ISC is functioning fine now you may consider just blocking the FIAV with some JB Weld, or drilling a hole for the ISC in the block-off plate and sandwiching it between the halves of the throttle body. Just a thought.
(bringing back the thread)
I have 2 fiav/isc plates sitting in the garage: one that ditches the fiav/keeps the isc, one that ditches the fiav/isc altogether. I just had my tb rebuilt so I'm contemplating between the two.
Before the TB rebuild, when I turned on my headlights, the rpm would drop a bit, and the car ran noticeably rougher. If I ditch the ISC will this be the same case, maybe worse? Or was it possibly due to a leaky FIAV/TB seals, both of which shouldnt be an issue anymore?
A/C is not used ever and the car wont be driven when cold winter comes around.
I have 2 fiav/isc plates sitting in the garage: one that ditches the fiav/keeps the isc, one that ditches the fiav/isc altogether. I just had my tb rebuilt so I'm contemplating between the two.
Before the TB rebuild, when I turned on my headlights, the rpm would drop a bit, and the car ran noticeably rougher. If I ditch the ISC will this be the same case, maybe worse? Or was it possibly due to a leaky FIAV/TB seals, both of which shouldnt be an issue anymore?
A/C is not used ever and the car wont be driven when cold winter comes around.
Personally if you don't have AC I'd ditch the whole ISC. Even in the cold all I had to do was bump up my base idle and it was fine. And I'm talking under the goose egg cold here. But if you remove the ISC you may have to adjust your base idle a bit for wildly different weather conditions. All it takes is popping the hood and turning the screw but some will not want to do that.
CP
Well-known member
When I manually turn on both stock front fans, my idle drops about 250rpm...with a functioning ISC. I think I'm gonna pull it and clean it up tonight.
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When I manually turn on both stock front fans, my idle drops about 250rpm...with a functioning ISC.
Thats what I don't want to happen. I just dont understand how some people have no issues running without an ISC and some do. How is that exactly?
When I manually turn on both stock front fans, my idle drops about 250rpm...with a functioning ISC.
Thats what I don't want to happen. I just dont understand how some people have no issues running without an ISC and some do. How is that exactly?
boostedinaz
Well-known member
Every car is differnt and everyone's opinion on what is a PIA is different. Right now my Talon has no functioning ISC. It drives me nuts that my car will idle pretty well during the day before it warms up. Once it is night time (lights on) and the fans kick on, my idle drops enough to make the car idle rough. That drives me nuts. For some, usually those that say no ISC works fine, they could care less if the car rattles like crazy or they have high idles when the engine has no load. I don't want either as they are a bandaid for a missing part.
I honestly see no reason to get rid of the ISC all together unless you just want to lower portion of the TB gone. To me the little savings in weight, complexity, or anything else is just not worth it to me. Now with my cams I NEED to have my ISC working because the car stalls out with the lope, the lights on, and the fans running.
I honestly see no reason to get rid of the ISC all together unless you just want to lower portion of the TB gone. To me the little savings in weight, complexity, or anything else is just not worth it to me. Now with my cams I NEED to have my ISC working because the car stalls out with the lope, the lights on, and the fans running.
well a failed ISC has fried more than one ECU...
The failing ISC is one reason I want it gone, less clutter is another.
Do you guys use some rtv or copper gasket silicon for between the plate and lower half? Just a bead around the outside of the plate, or does it need to go between each passage to seperate any leaks between them?
Do you guys use some rtv or copper gasket silicon for between the plate and lower half? Just a bead around the outside of the plate, or does it need to go between each passage to seperate any leaks between them?
boostedinaz
Well-known member
Quote:
well a failed ISC has fried more than one ECU...
That is what happened to mine and it will cost me all of 35.00 to fix. I would say that a good 5+ years of service, maybe more as I have only owned the car for that long, are more than enough to warrant keeping it in my case.
well a failed ISC has fried more than one ECU...
That is what happened to mine and it will cost me all of 35.00 to fix. I would say that a good 5+ years of service, maybe more as I have only owned the car for that long, are more than enough to warrant keeping it in my case.
boostedinaz
Well-known member
Quote:
Do you guys use some rtv or copper gasket silicon for between the plate and lower half? Just a bead around the outside of the plate, or does it need to go between each passage to seperate any leaks between them?
There is a rubber gasket between the two halves. If you are blocking it off completely then you don't need anything to seal it. If you are just using a plate to block of the FIAV then use a small amount of RTV to seal it.
Do you guys use some rtv or copper gasket silicon for between the plate and lower half? Just a bead around the outside of the plate, or does it need to go between each passage to seperate any leaks between them?
There is a rubber gasket between the two halves. If you are blocking it off completely then you don't need anything to seal it. If you are just using a plate to block of the FIAV then use a small amount of RTV to seal it.
atc250r
Staff member
Quote:
Now with my cams I NEED to have my ISC working because the car stalls out with the lope, the lights on, and the fans running.
You might have some other problem if that happens. Even with 280's mine will idle at 950rpm all day (once its warmed up a little) and then with the lights, cooling fans, rear def, and interior fan on it will only drop to 900 or so. Like you said, every car is different so who knows.
John
Now with my cams I NEED to have my ISC working because the car stalls out with the lope, the lights on, and the fans running.
You might have some other problem if that happens. Even with 280's mine will idle at 950rpm all day (once its warmed up a little) and then with the lights, cooling fans, rear def, and interior fan on it will only drop to 900 or so. Like you said, every car is different so who knows.
John
^I agree, plus with big cams it been doing its duty ok for me.
boostedinaz
Well-known member
Quote:
Quote:
Now with my cams I NEED to have my ISC working because the car stalls out with the lope, the lights on, and the fans running.
You might have some other problem if that happens. Even with 280's mine will idle at 950rpm all day (once its warmed up a little) and then with the lights, cooling fans, rear def, and interior fan on it will only drop to 900 or so. Like you said, every car is different so who knows.
John
Interesting. I can get it to idle at 850 with all the accesories on, but then when I turn them all off it idles up to about 1100. I do know that my Spal fans to put quite a load on even before the cams so that might be an issue. I will have to see what happens when I get my ECU back.
Quote:
Now with my cams I NEED to have my ISC working because the car stalls out with the lope, the lights on, and the fans running.
You might have some other problem if that happens. Even with 280's mine will idle at 950rpm all day (once its warmed up a little) and then with the lights, cooling fans, rear def, and interior fan on it will only drop to 900 or so. Like you said, every car is different so who knows.
John
Interesting. I can get it to idle at 850 with all the accesories on, but then when I turn them all off it idles up to about 1100. I do know that my Spal fans to put quite a load on even before the cams so that might be an issue. I will have to see what happens when I get my ECU back.
jogalant
Well-known member
Quote:
Personally if you don't have AC I'd ditch the whole ISC. Even in the cold all I had to do was bump up my base idle and it was fine. And I'm talking under the goose egg cold here. But if you remove the ISC you may have to adjust your base idle a bit for wildly different weather conditions.
Some of you may remember that Denso at one time had a nifty rpm adjustable module that came between the thermostat and ac switch. When idling anywhere from 650-1500, there was a sort of rheostat switch that you could set to what rpm you wanted the A/C compressor to kick in and conversely, cut off. I had this in my 1971 Corolla. You could have your a/c on and set your idle at say 800 rpm and everytime you had to slow down or stop and eventually go below the set rpm point, say 1250 rpm, the module would turn the compressor clutch off and you would be in "fan" mode. As soon as you're ready to accelerate, your a/c compressor kicks in when you go past 1250 rpm. Small price to pay in exchange for retaining a decent idle.
Now you can have your a/c and not worry about bogging down during idle /ubbthreads/images//graemlins/smile.gif
I've asked Jeff (Keydiver) to look into the possibility of incorporating this feature in his chips.
Personally if you don't have AC I'd ditch the whole ISC. Even in the cold all I had to do was bump up my base idle and it was fine. And I'm talking under the goose egg cold here. But if you remove the ISC you may have to adjust your base idle a bit for wildly different weather conditions.
Some of you may remember that Denso at one time had a nifty rpm adjustable module that came between the thermostat and ac switch. When idling anywhere from 650-1500, there was a sort of rheostat switch that you could set to what rpm you wanted the A/C compressor to kick in and conversely, cut off. I had this in my 1971 Corolla. You could have your a/c on and set your idle at say 800 rpm and everytime you had to slow down or stop and eventually go below the set rpm point, say 1250 rpm, the module would turn the compressor clutch off and you would be in "fan" mode. As soon as you're ready to accelerate, your a/c compressor kicks in when you go past 1250 rpm. Small price to pay in exchange for retaining a decent idle.
Now you can have your a/c and not worry about bogging down during idle /ubbthreads/images//graemlins/smile.gif
I've asked Jeff (Keydiver) to look into the possibility of incorporating this feature in his chips.
spoulson
Well-known member
I'm not so sure that is so much a 'feature' as it is a workaround. When idling in bumper to bumper traffic on a swelteringly hot day, I want my AC without having to free rev the engine to get it. Our cars have an ISC and A/C temp switch. No need for anything else, I think.
For my car, I used the FIAV blockoff that keeps the ISC. It provides a good service to my car, so I will replace it if it ever goes bad.
For my car, I used the FIAV blockoff that keeps the ISC. It provides a good service to my car, so I will replace it if it ever goes bad.
boostedinaz
Well-known member
Quote:
Quote:
Personally if you don't have AC I'd ditch the whole ISC. Even in the cold all I had to do was bump up my base idle and it was fine. And I'm talking under the goose egg cold here. But if you remove the ISC you may have to adjust your base idle a bit for wildly different weather conditions.
Some of you may remember that Denso at one time had a nifty rpm adjustable module that came between the thermostat and ac switch. When idling anywhere from 650-1500, there was a sort of rheostat switch that you could set to what rpm you wanted the A/C compressor to kick in and conversely, cut off. I had this in my 1971 Corolla. You could have your a/c on and set your idle at say 800 rpm and everytime you had to slow down or stop and eventually go below the set rpm point, say 1250 rpm, the module would turn the compressor clutch off and you would be in "fan" mode. As soon as you're ready to accelerate, your a/c compressor kicks in when you go past 1250 rpm. Small price to pay in exchange for retaining a decent idle.
Now you can have your a/c and not worry about bogging down during idle /ubbthreads/images//graemlins/smile.gif
I've asked Jeff (Keydiver) to look into the possibility of incorporating this feature in his chips.
We have something that does this only better, it is an ISC.
Quote:
Personally if you don't have AC I'd ditch the whole ISC. Even in the cold all I had to do was bump up my base idle and it was fine. And I'm talking under the goose egg cold here. But if you remove the ISC you may have to adjust your base idle a bit for wildly different weather conditions.
Some of you may remember that Denso at one time had a nifty rpm adjustable module that came between the thermostat and ac switch. When idling anywhere from 650-1500, there was a sort of rheostat switch that you could set to what rpm you wanted the A/C compressor to kick in and conversely, cut off. I had this in my 1971 Corolla. You could have your a/c on and set your idle at say 800 rpm and everytime you had to slow down or stop and eventually go below the set rpm point, say 1250 rpm, the module would turn the compressor clutch off and you would be in "fan" mode. As soon as you're ready to accelerate, your a/c compressor kicks in when you go past 1250 rpm. Small price to pay in exchange for retaining a decent idle.
Now you can have your a/c and not worry about bogging down during idle /ubbthreads/images//graemlins/smile.gif
I've asked Jeff (Keydiver) to look into the possibility of incorporating this feature in his chips.
We have something that does this only better, it is an ISC.
First off, thanks for the advice you guys gave! I decided to keep the ISC, but after putting everything back together, there are a couple (unrelated) minor issues I'm hoping you can help me with.
While the TB was out I also had the rad out, and replaced the thermostat. Cleaned it up, and had it professionally cleaned. For some reason my fan is running all the time. Second thing is that I'm getting a code 21 (coolant temp sensor) and my logger is showing a negative value when the car is up to temp. /ubbthreads/images//graemlins/dunno.gif
When I got my TB back, the TPS was installed backwards. I switched it around and hooked up the logger with the key turned to ON but the car not running. I can get it to read 0% on the logger, but then the max it will go to when the throttle plate is fully opened is something like 92%. I can get it to ~99%, but only when the closed throttle value is around 5%. (EDIT Nevermind - Realized that at idle it should be reading 10%, not 0%)
I don't see why this is happening. All the wiring wasn't changed and I didnt have this problem before.
Thanks
While the TB was out I also had the rad out, and replaced the thermostat. Cleaned it up, and had it professionally cleaned. For some reason my fan is running all the time. Second thing is that I'm getting a code 21 (coolant temp sensor) and my logger is showing a negative value when the car is up to temp. /ubbthreads/images//graemlins/dunno.gif
When I got my TB back, the TPS was installed backwards. I switched it around and hooked up the logger with the key turned to ON but the car not running. I can get it to read 0% on the logger, but then the max it will go to when the throttle plate is fully opened is something like 92%. I can get it to ~99%, but only when the closed throttle value is around 5%. (EDIT Nevermind - Realized that at idle it should be reading 10%, not 0%)
I don't see why this is happening. All the wiring wasn't changed and I didnt have this problem before.
Thanks
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