Modification to the air flow
10-18-2010, 11:06 PM
#11
Thread Starter
Join Date: Oct 2010
Location: Texas
Posts: 15
It wouldn't make that much of a difference the computer would be able to adjust like it is supposed. You most likely didn't put it back together right. Did u connect the hose on the back of the plenum? Will it run fine at engine speed? Mine did that for like a day and then i realized i was dumb and missed the connection.
what i did realized was that the first time i installed the plenum, there was a gasket close to the IAC but had no wholes so that made the car to consume more gas, as well the "service engine soon" light turned on. for that i made a small whole according to the ones that are made in the IAC valve and even more aceleration was obtained. But again the "service engine soon" turned back on"
10-19-2010, 05:51 AM
#12
Did you use a new IAC gasket. Those gaskets tend to dry up and don'y seal properly if re-used. Also check all the electrical connections and vacum lines. Plastic vacum lines tend to break easy with age.
10-19-2010, 07:30 AM
#13
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
Check the code(s) again to make certain it is the same.
Have you performed the IAC test indicated in the shop manual link I provided above? Unplug the electrical connector with the engine hot and idling, the engine speed should drop or perhaps even stall.
If it doesn't then check the resistance across the IAC terminals, it should be 6Ω to 13Ω; if it is not replace the IAC. If it is 6Ω to 13Ω then check the resistance between each pin and the IAC body, it should be 10kΩ or better; if not replace the IAC.
If the resistances check out then check the voltage at the red wire (pin 1) of the IAC harness connector with the key on and engine off. It should be >10.5V; if not there's an open or short in the harness--more likely an open as the that power comes from the same fuse that supplies the injectors--fuse #2 in the Central Junction Box (under the dash).
Have you performed the IAC test indicated in the shop manual link I provided above? Unplug the electrical connector with the engine hot and idling, the engine speed should drop or perhaps even stall.
If it doesn't then check the resistance across the IAC terminals, it should be 6Ω to 13Ω; if it is not replace the IAC. If it is 6Ω to 13Ω then check the resistance between each pin and the IAC body, it should be 10kΩ or better; if not replace the IAC.
If the resistances check out then check the voltage at the red wire (pin 1) of the IAC harness connector with the key on and engine off. It should be >10.5V; if not there's an open or short in the harness--more likely an open as the that power comes from the same fuse that supplies the injectors--fuse #2 in the Central Junction Box (under the dash).
Last edited by cliffyk; 10-19-2010 at 05:59 PM. Reason: added KOEO for clarity
10-19-2010, 05:20 PM
#15
Thread Starter
Join Date: Oct 2010
Location: Texas
Posts: 15
Check the code(s) again to make certain it is the same.
Have you performed the IAC test indicated in the shop manual link I provided above? Unplug the electrical connector with the engine hot and idling, the engine speed should drop or perhaps even stall.
If it doesn't then check the resistance across the IAC terminals, it should be 6Ω to 13Ω; if it is not replace the IAC. If it is 6Ω to 13Ω then check the resistance between each pin and the IAC body, it should be 10kΩ or better; if not replace the IAC.
If the resistances check out then check the voltage at the red wire (pin 1) of the IAC harness connector, it should be >10.5V; if not there's an open or short in the harness--more likely an open as the that power comes from the same fuse that supplies the injectors--fuse #2 in the Central Junction Box (under the dash).
Have you performed the IAC test indicated in the shop manual link I provided above? Unplug the electrical connector with the engine hot and idling, the engine speed should drop or perhaps even stall.
If it doesn't then check the resistance across the IAC terminals, it should be 6Ω to 13Ω; if it is not replace the IAC. If it is 6Ω to 13Ω then check the resistance between each pin and the IAC body, it should be 10kΩ or better; if not replace the IAC.
If the resistances check out then check the voltage at the red wire (pin 1) of the IAC harness connector, it should be >10.5V; if not there's an open or short in the harness--more likely an open as the that power comes from the same fuse that supplies the injectors--fuse #2 in the Central Junction Box (under the dash).
there is something i observed and i would like to inform. When i hit ignition with the electrical cable connected to the IAC, is like if someone hit the gas for a couple of seconds and then it restores, then i turn it off. Then I tried turning the engine on with the cable off, and the engine started but no aceleration was performed. Is there something related with the problem????
10-19-2010, 05:52 PM
#16
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Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
10-19-2010, 05:58 PM
#17
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
i unplugged the cable and the speed did not droped. i will have to perform the second test.
there is something i observed and i would like to inform. When i hit ignition with the electrical cable connected to the IAC, is like if someone hit the gas for a couple of seconds and then it restores, then i turn it off. Then I tried turning the engine on with the cable off, and the engine started but no aceleration was performed. Is there something related with the problem????
there is something i observed and i would like to inform. When i hit ignition with the electrical cable connected to the IAC, is like if someone hit the gas for a couple of seconds and then it restores, then i turn it off. Then I tried turning the engine on with the cable off, and the engine started but no aceleration was performed. Is there something related with the problem????
Most likely the IAC is bad, however you should perform the electrical tests, particularly the KOEO (Key On Engine Off) voltage test to check for 10.5V at the red wire in the IAC harness end connector.
10-25-2010, 11:49 PM
#18
Thread Starter
Join Date: Oct 2010
Location: Texas
Posts: 15
I have found the solution and u will not beleive what it was.
I whent with another friend who helped me intal the plenum. after doing all the tests u guys provided me we found that the valve was ok
and ecu as well but we never thought that this error was a unnoticible mistake.
u might say that it was mere luck that we found the problem. so the issue was in the aceleration device that is in the pelnum. We found out that the last owner maybe folded a small part of this device to increase aceleration. this is like a silver base piece that is held by a small screw. so we unfolded this silver base piece, disconnected the battery cable, waited for 5 to 8 minutes, ignitioned the car and the error light did not turned on...
After several laps we made in the car the light has not turned on yet, so it is kind of a funny situation.
But i do recognize the hard effort u guys implemented in my comment and it is greatly appreciated, i just hope this info can help somebody else
I whent with another friend who helped me intal the plenum. after doing all the tests u guys provided me we found that the valve was ok
and ecu as well but we never thought that this error was a unnoticible mistake.
u might say that it was mere luck that we found the problem. so the issue was in the aceleration device that is in the pelnum. We found out that the last owner maybe folded a small part of this device to increase aceleration. this is like a silver base piece that is held by a small screw. so we unfolded this silver base piece, disconnected the battery cable, waited for 5 to 8 minutes, ignitioned the car and the error light did not turned on...
After several laps we made in the car the light has not turned on yet, so it is kind of a funny situation.
But i do recognize the hard effort u guys implemented in my comment and it is greatly appreciated, i just hope this info can help somebody else
10-26-2010, 06:37 AM
#19
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
I have found the solution and u will not beleive what it was.
I whent with another friend who helped me intal the plenum. after doing all the tests u guys provided me we found that the valve was ok
and ecu as well but we never thought that this error was a unnoticible mistake.
u might say that it was mere luck that we found the problem. so the issue was in the aceleration device that is in the pelnum. We found out that the last owner maybe folded a small part of this device to increase aceleration. this is like a silver base piece that is held by a small screw. so we unfolded this silver base piece, disconnected the battery cable, waited for 5 to 8 minutes, ignitioned the car and the error light did not turned on...
After several laps we made in the car the light has not turned on yet, so it is kind of a funny situation.
But i do recognize the hard effort u guys implemented in my comment and it is greatly appreciated, i just hope this info can help somebody else
I whent with another friend who helped me intal the plenum. after doing all the tests u guys provided me we found that the valve was ok
and ecu as well but we never thought that this error was a unnoticible mistake.
u might say that it was mere luck that we found the problem. so the issue was in the aceleration device that is in the pelnum. We found out that the last owner maybe folded a small part of this device to increase aceleration. this is like a silver base piece that is held by a small screw. so we unfolded this silver base piece, disconnected the battery cable, waited for 5 to 8 minutes, ignitioned the car and the error light did not turned on...
After several laps we made in the car the light has not turned on yet, so it is kind of a funny situation.
But i do recognize the hard effort u guys implemented in my comment and it is greatly appreciated, i just hope this info can help somebody else
There is no such device in a stock, or reputable after market plenumą-- it must be some silly after market thing that should likely be removed...
----------------------------------------------
ą - There is one after market plenum, which was from NOT a reputable vendor, that has a vane inside to allegedly "improve flow". It was originally sold by Granatelli, however it's design and implementation were so lame that they apparently sold off the whole lot--they turned up on eBay for as little as $30.
Does it look like this?
It's the same casting as used by C&L:
But, lobotomised to make it look "trick" by reducing interior volume and therefore air flow.
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