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Air filter by NiotaFiero
Started on: 09-25-2013 09:30 AM
Replies: 15 (266 views)
Last post by: NiotaFiero on 09-27-2013 08:55 AM
NiotaFiero
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Report this Post09-25-2013 09:30 AM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
Will not having an air filter installed affect the idle rpm's?
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Report this Post09-25-2013 09:44 AM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Generally, no, it won't. It does however, greatly increase the chances of you sucking dirt into the intake, and the dirt and dust particles being sucked in, can get stuck in the throttle body and idle air inlet, creating blockages and preventing air from getting in.

Most likely causes of idle issues are TPS or IAC, or vacuum leaks. Describing the exact symptoms of your idle issues would make it much easier to give advice on where to look.
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NiotaFiero
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Report this Post09-25-2013 10:12 AM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
I tried the aluminum between the EGR tube and the upper intake and it reduced the idle somewhat so I guess I need to remove the tube and check it out. What confuses me is that someone said to remove the snorkel and block the hole in the floor of it and if that made it idle down then the IAC was bad. I did this and it reduced the idle down to about 900 rpm's, so is the IAC bad?
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NiotaFiero
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Report this Post09-25-2013 10:17 AM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post

NiotaFiero

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Sorry didn't mean to double post and don't know how to delete.

[This message has been edited by NiotaFiero (edited 09-25-2013).]

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carbon
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Report this Post09-25-2013 10:36 AM Click Here to See the Profile for carbonSend a Private Message to carbonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NiotaFiero:

I tried the aluminum between the EGR tube and the upper intake and it reduced the idle somewhat so I guess I need to remove the tube and check it out. What confuses me is that someone said to remove the snorkel and block the hole in the floor of it and if that made it idle down then the IAC was bad. I did this and it reduced the idle down to about 900 rpm's, so is the IAC bad?


No, 900RPM means you have a vacuum leak. The idle should get ugly and drop to like 500RPM when you plug the IAC hole, most Fieros can only run like this if they are good and warm... at that point the idle is based on only what air can get around the closed throttle plate (which was set at the factory for a minimum air position, don't mess with it), or any other leak in the system.

 
quote
Originally posted by NiotaFiero:

Sorry didn't mean to double post and don't know how to delete.



It's ok... don't be scared. It happens to all of us at some point...

[This message has been edited by carbon (edited 09-25-2013).]

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Report this Post09-25-2013 10:46 AM Click Here to See the Profile for carbonSend a Private Message to carbonEdit/Delete MessageReply w/QuoteDirect Link to This Post
You can reset the IAC by jumping the AB terminals in the ALDL connector and turning on the ignition... you should hear the IAC clicking rapidly, trying to close itself. This is one of the reasons that idle quality isn't very great when you are setting the timing.

If you are sitting at 900RPM with the IAC port blocked, and the EGR block off plate wasn't definitive, you're gonna have to dig deeper for a vacuum leak. What was the idle speed that initially caused you to look into the issue in the first place? Where did you start?

Another behavior to be aware of is that in normal function, blocking the IAC port will cause the ECM to fully open the IAC to try to restore normal idle, if it's low... when you uncover it, the engine will speed up momentarily while the ECM races to close the IAC to get back to normal idle.

If blocking the IAC port doesn't seem to make much difference, then the ECM already had it mostly closed in a futile fight to bring the idle down against the will of the vacuum leak.

[This message has been edited by carbon (edited 09-25-2013).]

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Report this Post09-25-2013 10:47 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NiotaFiero:

I tried the aluminum between the EGR tube and the upper intake and it reduced the idle somewhat so I guess I need to remove the tube and check it out. What confuses me is that someone said to remove the snorkel and block the hole in the floor of it and if that made it idle down then the IAC was bad. I did this and it reduced the idle down to about 900 rpm's, so is the IAC bad?


With everything good, you can block the IAC hole and stall the car....or very nearly stall the car. When you blocked your IAC, the car was running because there was air getting into the intake from some other place. So you do not know for sure if your IAC is bad or good yet....but what you do know is that there is still a leak somewhere.
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NiotaFiero
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Report this Post09-25-2013 11:00 AM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by carbon:

You can reset the IAC by jumping the AB terminals in the ALDL connector and turning on the ignition... you should hear the IAC clicking rapidly, trying to close itself. This is one of the reasons that idle quality isn't very great when you are setting the timing.

If you are sitting at 900RPM with the IAC port blocked, and the EGR block off plate wasn't definitive, you're gonna have to dig deeper for a vacuum leak. What was the idle speed that initially caused you to look into the issue in the first place? Where did you start?

Another behavior to be aware of is that in normal function, blocking the IAC port will cause the ECM to fully open the IAC to try to restore normal idle, if it's low... when you uncover it, the engine will speed up momentarily while the ECM races to close the IAC to get back to normal idle.

If blocking the IAC port doesn't seem to make much difference, then the ECM already had it mostly closed in a futile fight to bring the idle down against the will of the vacuum leak.

The reason I started hunting solutions is that the engine was idling at 2000 RPM.When I slide the aluminum in place it drops to around 900-1100 rpm's as measured by my tach. Without the aluminium in place and covering the IAC port I get the same reduction in idle RPM's--900-1100. I have read that when I cover the IAC port ,it should idle down so low that it could kill the engine, but it doesn't, it just drops to 900 RPM's minimum.

[This message has been edited by NiotaFiero (edited 09-25-2013).]

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TopNotch
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Report this Post09-25-2013 12:35 PM Click Here to See the Profile for TopNotchClick Here to visit TopNotch's HomePageSend a Private Message to TopNotchEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you put a plate on your EGR valve, and the idle RPM drops significantly, it doesn't mean you have a bad EGR tube, it means you have a leaking EGR valve. If the tube is leaking, RPM's will be high with or without the plate.
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NiotaFiero
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Report this Post09-25-2013 02:00 PM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by TopNotch:

If you put a plate on your EGR valve, and the idle RPM drops significantly, it doesn't mean you have a bad EGR tube, it means you have a leaking EGR valve. If the tube is leaking, RPM's will be high with or without the plate.

The plate I put on is between the EGR tube and the plenum. Does your reply still apply?
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Report this Post09-25-2013 02:33 PM Click Here to See the Profile for carbonSend a Private Message to carbonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NiotaFiero:

The plate I put on is between the EGR tube and the plenum. Does your reply still apply?


He is saying move the plate to the other end of the tube to isolate the pipe from the valve... The holes are shaped the same so your plate should work on either end.

If blocking the EGR system at the plenum and plugging the IAC port results in 900RPM from 2000RPM, you most definitely have a problem with your EGR system. However, because your idle is still high with the IAC blocked, you have at least one other leak.

[This message has been edited by carbon (edited 09-25-2013).]

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NiotaFiero
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Report this Post09-25-2013 02:41 PM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by carbon:


He is saying move the plate to the other end of the tube to isolate the pipe from the valve... The holes are shaped the same so your plate should work on either end.

If blocking the EGR system at the plenum and plugging the IAC port results in 900RPM from 2000RPM, you most definitely have a problem with your EGR system. However, because your idle is still high with the IAC blocked, you have at least one other leak.

Thanks, I'll move my plate and check it out that way.

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NiotaFiero
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Report this Post09-26-2013 04:24 PM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NiotaFiero:

[QUOTE]Originally posted by carbon:


He is saying move the plate to the other end of the tube to isolate the pipe from the valve... The holes are shaped the same so your plate should work on either end.

If blocking the EGR system at the plenum and plugging the IAC port results in 900RPM from 2000RPM, you most definitely have a problem with your EGR system. However, because your idle is still high with the IAC blocked, you have at least one other leak.

Thanks, I'll move my plate and check it out that way.
[/QUOTE]
So, I moved the plate to the other end of the tube and then the idle went to minimum 1500 rpm's. Then I moved it back to between the tube and plenum and rpm's drop to 1000. If I pull the snorkel and plug the hole in the base of it then rpm drops to around 600-700 rpm's.
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NiotaFiero
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Report this Post09-26-2013 04:33 PM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NiotaFiero:

[QUOTE]Originally posted by carbon:


He is saying move the plate to the other end of the tube to isolate the pipe from the valve... The holes are shaped the same so your plate should work on either end.

If blocking the EGR system at the plenum and plugging the IAC port results in 900RPM from 2000RPM, you most definitely have a problem with your EGR system. However, because your idle is still high with the IAC blocked, you have at least one other leak.

Thanks, I'll move my plate and check it out that way.
[/QUOTE]
So, I moved the plate to the other end of the tube and then the idle went to minimum 1500 rpm's. Then I moved it back to between the tube and plenum and rpm's drop to 1000. If I pull the snorkel and plug the hole in the base of it then rpm drops to around 600-700 rpm's.
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Report this Post09-27-2013 08:21 AM Click Here to See the Profile for carbonSend a Private Message to carbonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NiotaFiero:
So, I moved the plate to the other end of the tube and then the idle went to minimum 1500 rpm's. Then I moved it back to between the tube and plenum and rpm's drop to 1000. If I pull the snorkel and plug the hole in the base of it then rpm drops to around 600-700 rpm's.


So you found your problem... EGR system. The stock idle is around 900-1000, so if blocking the IAC drops it to 600-700, the IAC is probably fine. Check that EGR pipe! Even though there was a 500RPM change between having the block off plate on one side or the other, I think just the manipulation of the EGR pipe to move it around could make the crack open up or pinch shut.
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NiotaFiero
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Report this Post09-27-2013 08:55 AM Click Here to See the Profile for NiotaFieroClick Here to Email NiotaFieroSend a Private Message to NiotaFieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by carbon:


So you found your problem... EGR system. The stock idle is around 900-1000, so if blocking the IAC drops it to 600-700, the IAC is probably fine. Check that EGR pipe! Even though there was a 500RPM change between having the block off plate on one side or the other, I think just the manipulation of the EGR pipe to move it around could make the crack open up or pinch shut.


Thanks for the reply, EGR Tube-coming off!!!--for closer look.

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