Cold start problem.
MARKUSIUDIUS
02-13-2002, 02:21 AM
Since I installed my blower I have had problems with cold start up. Because I have the original throttle face sealed (as I installed another before the blower) the idle temperature air port is know longer in use (dont know what its called but that sounds cool). Is there some sort of temperature solenoid etc that I could install to come on when cold ( to suck in more air) and switch of when warm? Or should I just switch around throttle faces and run long heater hoses. Id prefer a simple solution if any.Thanks:flash:
Moppie
02-13-2002, 04:29 AM
Mate! what an awsome set up! You must have had some fun making brackets and finding a crank pully to run the blower.
I always thought the VTEC honda engines used oil temp for the cold start cycle, but prehaps the H22 is differnt.
Is the idle temp air port as you called it a Vucume line? If so then the cold idle control solonoid is working but not getting any vacume to operate the throttle. Simple solution plumb it in to some vacum.
You dont happen to have any pics handy do you? :)
I always thought the VTEC honda engines used oil temp for the cold start cycle, but prehaps the H22 is differnt.
Is the idle temp air port as you called it a Vucume line? If so then the cold idle control solonoid is working but not getting any vacume to operate the throttle. Simple solution plumb it in to some vacum.
You dont happen to have any pics handy do you? :)
fritz_269
02-13-2002, 06:36 PM
Originally posted by Moppie
I always thought the VTEC honda engines used oil temp for the cold start cycle, but prehaps the H22 is differnt.
H22 plumbs coolant lines to two parts of the intake apparatus:
#1) To the IAC (Idle Air Control) Valve. The intention here is to get the idle valve warm to heat the incoming cold air at start-up. This is the line that a lot of people in warmer climates just bypass; hoping they'll get a smidgen more power by keeping the TB a little cooler. The temperature of the coolant in the IAC does not directly affect the opening or closing of the IAC valve. I don't think this is Mark's problem.
#2) To the Fast Idle Thermo Valve. This is simply a thermowax-spring attached to a plunger which opens a tiny airway to bypass the throttle blade when cold, thus keeping the revs up. As the coolant heats up, the thermowax expands, closes the plunger, the airway is shut off, and the revs drop down to the set idle.
I think what Mark is looking for is something to replace the Fast Idle Thermo Valve. Something to keep the revs up until the car is warm - Yes?
I can think of two and 1/2 solutions off the top of my head -
1) The Automatic Solution - pull the Fast Idle Thermo Valve off the bottom of the original TB, epoxy threaded or barbed pipes into the air and coolant holes. Be careful, as it's a fairly delicate device. Then plug or plate the holes on the bottom of the original TB where that Thermo Valve was. This sounds like a lot of work.. :(
2) The Manual Solution - buy a 12V, small, solenoid valve with something like 1/2" or 3/8" inlets and outlets; preferably it should be of the Normally Closed type. Just rig up a switch under the dash to open the solenoid. Connect the solenoid to flow across the throttle blade when open. Adjust the amount of air bypass by varying the size and lenght of the bypass tubes, or add a restrictor washer in-line.
With the switch on, the solenoid is open and will pass air around the throttle blade, resulting in a fast idle. Once you've warmed up, just flip the switch off, the solenoid will close and the idle will drop to where it was before.
Since the pressure differential is so low, any solenoid for low pressure water would probably work just fine too (like one for an automatic sprinkler system - although that might not be pretty, it is NC and real cheap!) A thermoplastic process control valve might run you between $20-$40 US, but if you can find one at a surplus store, they should only be a couple of bucks. You might be careful in the mounting so that it doesn't vibrate itself to death.
2 1/2) The Automatic Manual Solution - Build the Manual Solution, get it all to work, then get a temperature controller for an electric fan. Hook it up through a relay to turn off the solenoid when the coolant reaches the set temperature.
QED. :)
You dont happen to have any pics handy do you? :) You gotta check out the Prelude forum! :D
http://www.automotiveforums.com/vbulletin/t24983.html
http://www.automotiveforums.com/vbulletin/t20548.html
:cool:
I always thought the VTEC honda engines used oil temp for the cold start cycle, but prehaps the H22 is differnt.
H22 plumbs coolant lines to two parts of the intake apparatus:
#1) To the IAC (Idle Air Control) Valve. The intention here is to get the idle valve warm to heat the incoming cold air at start-up. This is the line that a lot of people in warmer climates just bypass; hoping they'll get a smidgen more power by keeping the TB a little cooler. The temperature of the coolant in the IAC does not directly affect the opening or closing of the IAC valve. I don't think this is Mark's problem.
#2) To the Fast Idle Thermo Valve. This is simply a thermowax-spring attached to a plunger which opens a tiny airway to bypass the throttle blade when cold, thus keeping the revs up. As the coolant heats up, the thermowax expands, closes the plunger, the airway is shut off, and the revs drop down to the set idle.
I think what Mark is looking for is something to replace the Fast Idle Thermo Valve. Something to keep the revs up until the car is warm - Yes?
I can think of two and 1/2 solutions off the top of my head -
1) The Automatic Solution - pull the Fast Idle Thermo Valve off the bottom of the original TB, epoxy threaded or barbed pipes into the air and coolant holes. Be careful, as it's a fairly delicate device. Then plug or plate the holes on the bottom of the original TB where that Thermo Valve was. This sounds like a lot of work.. :(
2) The Manual Solution - buy a 12V, small, solenoid valve with something like 1/2" or 3/8" inlets and outlets; preferably it should be of the Normally Closed type. Just rig up a switch under the dash to open the solenoid. Connect the solenoid to flow across the throttle blade when open. Adjust the amount of air bypass by varying the size and lenght of the bypass tubes, or add a restrictor washer in-line.
With the switch on, the solenoid is open and will pass air around the throttle blade, resulting in a fast idle. Once you've warmed up, just flip the switch off, the solenoid will close and the idle will drop to where it was before.
Since the pressure differential is so low, any solenoid for low pressure water would probably work just fine too (like one for an automatic sprinkler system - although that might not be pretty, it is NC and real cheap!) A thermoplastic process control valve might run you between $20-$40 US, but if you can find one at a surplus store, they should only be a couple of bucks. You might be careful in the mounting so that it doesn't vibrate itself to death.
2 1/2) The Automatic Manual Solution - Build the Manual Solution, get it all to work, then get a temperature controller for an electric fan. Hook it up through a relay to turn off the solenoid when the coolant reaches the set temperature.
QED. :)
You dont happen to have any pics handy do you? :) You gotta check out the Prelude forum! :D
http://www.automotiveforums.com/vbulletin/t24983.html
http://www.automotiveforums.com/vbulletin/t20548.html
:cool:
MARKUSIUDIUS
02-15-2002, 07:01 AM
Fritz you really love this shit when I come over in October it would be great to meet.
I thought of the idea with the thermo fan controller to cut of a solenoid at a certain temp but these thermometers are a positive type, meaning they send a charge or open at a certain temp setting not take one away or close.
I need something to switch off at a certain temp not switch on. If a solenoid was already open and then it needed a charge to close I think this would be cool but???
Anyhow I think the easiest way is to switch throttle faces over and run long water temp hosing.
Thanks guys and when shes finished I will post better photos and a complete detailed guide of the installation.
New mag states a Sti at a 14.2 sec quarter mile and a M3 at 13.9. Cannot wait until I fry em.:flash:
I thought of the idea with the thermo fan controller to cut of a solenoid at a certain temp but these thermometers are a positive type, meaning they send a charge or open at a certain temp setting not take one away or close.
I need something to switch off at a certain temp not switch on. If a solenoid was already open and then it needed a charge to close I think this would be cool but???
Anyhow I think the easiest way is to switch throttle faces over and run long water temp hosing.
Thanks guys and when shes finished I will post better photos and a complete detailed guide of the installation.
New mag states a Sti at a 14.2 sec quarter mile and a M3 at 13.9. Cannot wait until I fry em.:flash:
Tofuboy
02-15-2002, 03:41 PM
2) The Manual Solution - buy a 12V, small, solenoid valve with something like 1/2" or 3/8" inlets and outlets; preferably it should be of the Normally Closed type. Just rig up a switch under the dash to open the solenoid. Connect the solenoid to flow across the throttle blade when open. Adjust the amount of air bypass by varying the size and lenght of the bypass tubes, or add a restrictor washer in-line.
Fast idle?
Fritz, if ECT/CTS is available, is there anyway we can try using that as a signal to turn off the solenoid?
Fast idle?
Fritz, if ECT/CTS is available, is there anyway we can try using that as a signal to turn off the solenoid?
fritz_269
02-15-2002, 04:02 PM
Originally posted by MARKUSIUDIUS
Fritz you really love this shit when I come over in October it would be great to meet.If you're gonna be in the LA area, that would be cool - shoot me an email when you know when you're gonna be in town.I thought of the idea with the thermo fan controller to cut of a solenoid at a certain temp but these thermometers are a positive type, meaning they send a charge or open at a certain temp setting not take one away or close. I need something to switch off at a certain temp not switch on. If a solenoid was already open and then it needed a charge to close I think this would be cool but???Right.
All you need to do is hook the 'positive type' controller to the coil of an automotive relay. Then put the NC (normally closed) relay contacts in series with the voltage supply to the solenoid.
When the temp is cold, the thermo controller will send 0V, the relay coil will not be energized, the relay contacts will conduct (they're NC), and the solenoid will be open.
When the temp is hot, the thermo controller will send 12V, the relay coil will be energized, the relay contacts will open, and the solenoid will close.
Easy. :D
Anyhow I think the easiest way is to switch throttle faces over and run long water temp hosing.
You'll have to do a little re-plumbing on the stock throttle body if you remove it from the intake plenum - I think both coolant and air bypass lines go into the intake plenum casting. But the Fast Idle Thermo Valve should come right with it.
:cool:
Fritz you really love this shit when I come over in October it would be great to meet.If you're gonna be in the LA area, that would be cool - shoot me an email when you know when you're gonna be in town.I thought of the idea with the thermo fan controller to cut of a solenoid at a certain temp but these thermometers are a positive type, meaning they send a charge or open at a certain temp setting not take one away or close. I need something to switch off at a certain temp not switch on. If a solenoid was already open and then it needed a charge to close I think this would be cool but???Right.
All you need to do is hook the 'positive type' controller to the coil of an automotive relay. Then put the NC (normally closed) relay contacts in series with the voltage supply to the solenoid.
When the temp is cold, the thermo controller will send 0V, the relay coil will not be energized, the relay contacts will conduct (they're NC), and the solenoid will be open.
When the temp is hot, the thermo controller will send 12V, the relay coil will be energized, the relay contacts will open, and the solenoid will close.
Easy. :D
Anyhow I think the easiest way is to switch throttle faces over and run long water temp hosing.
You'll have to do a little re-plumbing on the stock throttle body if you remove it from the intake plenum - I think both coolant and air bypass lines go into the intake plenum casting. But the Fast Idle Thermo Valve should come right with it.
:cool:
fritz_269
02-15-2002, 04:13 PM
Originally posted by Tofuboy
Fast idle?
Fritz, if ECT/CTS is available, is there anyway we can try using that as a signal to turn off the solenoid?
Well, sure, but that would involve basically just building a thermo controller like the ones for the fan.
Unless you're really into electronics, its probably far more reliable, and not much more expensive to buy an off-the-shelf automotive thermo controller. If you care - the ECT sensor is a negative tempco thermistor - the ECU runs a constant voltage across a resistive divider with the thermistor and reads the resulting voltage. You'd need to tap into that wire with a high-impedance amp and use a comparator to set the switch point.
Unfortunately, tapping into the stock fan controller won't work very well; the cooling fans don't turn on until 203 degrees - often times they're off during normal driving.
:cool:
Fast idle?
Fritz, if ECT/CTS is available, is there anyway we can try using that as a signal to turn off the solenoid?
Well, sure, but that would involve basically just building a thermo controller like the ones for the fan.
Unless you're really into electronics, its probably far more reliable, and not much more expensive to buy an off-the-shelf automotive thermo controller. If you care - the ECT sensor is a negative tempco thermistor - the ECU runs a constant voltage across a resistive divider with the thermistor and reads the resulting voltage. You'd need to tap into that wire with a high-impedance amp and use a comparator to set the switch point.
Unfortunately, tapping into the stock fan controller won't work very well; the cooling fans don't turn on until 203 degrees - often times they're off during normal driving.
:cool:
MARKUSIUDIUS
02-20-2002, 01:15 AM
posted Fritz
If you're gonna be in the LA area, that would be cool - shoot me an email when you know when you're gonna be in town.
We are coming in mid October for a friends wedding in vegas so we will speak before then.
posted Fritz
All you need to do is hook the 'positive type' controller to the coil of an automotive relay. Then put the NC (normally closed) relay contacts in series with the voltage supply to the solenoid.
Will try for sure as it sounds easy.
posted Fritz
Easy.
I hope so otherwise I will send you the bill;)
If you're gonna be in the LA area, that would be cool - shoot me an email when you know when you're gonna be in town.
We are coming in mid October for a friends wedding in vegas so we will speak before then.
posted Fritz
All you need to do is hook the 'positive type' controller to the coil of an automotive relay. Then put the NC (normally closed) relay contacts in series with the voltage supply to the solenoid.
Will try for sure as it sounds easy.
posted Fritz
Easy.
I hope so otherwise I will send you the bill;)
fritz_269
02-20-2002, 04:08 PM
Originally posted by MARKUSIUDIUS
I hope so otherwise I will send you the bill;)
Right after you pay the consulting fee. ;)
I hope so otherwise I will send you the bill;)
Right after you pay the consulting fee. ;)
MARKUSIUDIUS
02-21-2002, 02:00 AM
If i get time this weekend I'll pop down to the local auto elect and see what we can rumage.
posted fritz_269
Right after you pay the consulting fee.
Send me yours and then I'll send mine. Thanks for the free help.:flash:
posted fritz_269
Right after you pay the consulting fee.
Send me yours and then I'll send mine. Thanks for the free help.:flash:
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