Engine surge w/ ac on

shadow stang · 05-29-2005, 11:09 PM

I have a 2004 GT, 5-speed. I've noticed that when I have my AC on and at a stop, the engine will sure past 1000prm up to about 1500 or so. But it only happens when the fan kicks on from the AC. I have a 75mm TB and new Plenum. Could this be related? I have other mods also. Any help or suggestions would be appreciated. Thanks in advance.

silentbullitt · 05-29-2005, 11:48 PM

My cobra did that when ever I would turn on the A/C. It winded up being that one of my A/C lines was kinked up pretty good because of the installation of my tubular k-member. Found out to late though, cost me new line and compressor before I sold it.

**bighoss88lx** · 05-29-2005, 11:49 PM

Quote:

Originally Posted by shadow stang

I have a 2004 GT, 5-speed. I've noticed that when I have my AC on and at a stop, the engine will sure past 1000prm up to about 1500 or so. But it only happens when the fan kicks on from the AC. I have a 75mm TB and new Plenum. Could this be related? I have other mods also. Any help or suggestions would be appreciated. Thanks in advance.

I had an '03 GT at work that would surge and die when the fan cut on for the A/C and was hell to start. It ended up being the crank sensor. Dunno if that has any relation to your problem or not.

shadow stang · 05-30-2005, 01:58 PM

Thanks for the info guys. What's weird though, is when the AC is off and I hit the gas, you can hear a whoosh noise from the TB when it opens up. BUT, I popped the hood open, turned the AC on, and listened the the TB. When the fan kicks on from the AC, you can hear a whoosh also then goes away when the fan kicks off.

**TrueBlueVenom** · 05-30-2005, 02:12 PM

hit an Auto Zone and have them run codes for you. if it's the crank sensor (per Hoss' thoughts), there will be a specific error for it (I forget that error code).

Here's some links that I've posted on AAS that are useful (would make nice for a new stickied thread.

):

OBD and DTC info
Codes and general issue descriptions:
http://proficientmustang.com/ecm_codes.htm
http://forums.stangnet.com/showthread.php?mode=hybrid&t=421143

Breakdown description of codes:
http://www.fordforums.com/showthread.php?t=81076

Here's an all inclusive PDF (codes, meanings, possible issues/resolutions):
http://minivanmadness.com/pdf/files/obd2%20codes%20and%20troubleshooting.pdf

shadow stang · 06-03-2005, 04:17 PM

Well, turns out the condenser went out. It's at the dealership right now being fixed. Good thing it's covered under warranty. After that, I have to run it up to the shop to have my TB adjusted. Anyways, thanks for the info guys. I sure do appreciate your help. :jeff:

fastang7 · 06-11-2005, 06:59 PM

75mm might be to large if you are stock or are near enough to stock. 75mm would be good for a cams/headworked engine

Zylone · 06-11-2005, 10:13 PM

One other thing to look at is if you have an under the hood CAI installed, with the filter just hangin there, you could get fan wash that will screw with the MAF... just something to think about if that is the case...

shadow stang · 06-13-2005, 02:09 PM

I have an appointment with CCS to get my car working right. :jeff:
I go on the 25th.

shadow stang · 06-22-2005, 11:30 AM

Well took a drive down to CCS on 6/18 just to see where it was at. Jim was there. I was amazed when he asked if I had time that day to get it done! I was supposed to go this Saturday the 25th. That really meant a lot to me for him to work on my car sooner. Car is running better and feels stronger than it did with the other tune. Big thumbs up to Jim. What a guy, knows his shit, and he has great customer service!! Pretty much, it was the tune I had before that was causing problems. Jim did not stop until it was fixed. I just wanted everyone to know my experience and how much I greatly appreciated his service and the work he did to my car!! Thanks Jim!!! :jeff:

05-29-2005, 11:09 PM	#1
shadow stang Registered User Join Date: Jan 2004 Location: San Antonio Posts: 218 Trader Rating: (0)	Engine surge w/ ac on I have a 2004 GT, 5-speed. I've noticed that when I have my AC on and at a stop, the engine will sure past 1000prm up to about 1500 or so. But it only happens when the fan kicks on from the AC. I have a 75mm TB and new Plenum. Could this be related? I have other mods also. Any help or suggestions would be appreciated. Thanks in advance.

05-30-2005, 02:12 PM	#5
TrueBlueVenom in a happy place Join Date: Jun 2003 Location: San Antonio Posts: 5,825 Trader Rating: (0)	hit an Auto Zone and have them run codes for you. if it's the crank sensor (per Hoss' thoughts), there will be a specific error for it (I forget that error code). Here's some links that I've posted on AAS that are useful (would make nice for a new stickied thread. ): OBD and DTC info Codes and general issue descriptions: http://proficientmustang.com/ecm_codes.htm http://forums.stangnet.com/showthread.php?mode=hybrid&t=421143 Breakdown description of codes: http://www.fordforums.com/showthread.php?t=81076 Here's an all inclusive PDF (codes, meanings, possible issues/resolutions): http://minivanmadness.com/pdf/files/obd2%20codes%20and%20troubleshooting.pdf __________________ -John 2001 Cobra #443, 1 of 316 L2 coupes, born: 4/11/01 Mod Notes: #1 - Per LSS Classified Rules, please post asking price(s) or the thread(s) will be closed. #2 - Please do not hijack threads. Take off-topic or personal inquiries to PMs. This includes For Sale items that you "feel" are priced too high.

06-11-2005, 06:59 PM	#7
fastang7 sarcasm IS art Join Date: Jan 2005 Location: huntsville Posts: 835 Trader Rating: (0)	75mm might be to large if you are stock or are near enough to stock. 75mm would be good for a cams/headworked engine __________________

06-11-2005, 10:13 PM	#8
Zylone 5.ohhh Join Date: Jun 2003 Location: San Antonio, Tx. Posts: 1,121 Trader Rating: (0)	One other thing to look at is if you have an under the hood CAI installed, with the filter just hangin there, you could get fan wash that will screw with the MAF... just something to think about if that is the case... __________________ #1 swamp donkey

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05-29-2005, 11:48 PM	#2
silentbullitt Registered User Join Date: May 2005 Location: san antonio Posts: 547 Trader Rating: (0)	My cobra did that when ever I would turn on the A/C. It winded up being that one of my A/C lines was kinked up pretty good because of the installation of my tubular k-member. Found out to late though, cost me new line and compressor before I sold it.

05-30-2005, 01:58 PM	#4
shadow stang Registered User Join Date: Jan 2004 Location: San Antonio Posts: 218 Trader Rating: (0)	Thanks for the info guys. What's weird though, is when the AC is off and I hit the gas, you can hear a whoosh noise from the TB when it opens up. BUT, I popped the hood open, turned the AC on, and listened the the TB. When the fan kicks on from the AC, you can hear a whoosh also then goes away when the fan kicks off.

06-03-2005, 04:17 PM	#6
shadow stang Registered User Join Date: Jan 2004 Location: San Antonio Posts: 218 Trader Rating: (0)	Well, turns out the condenser went out. It's at the dealership right now being fixed. Good thing it's covered under warranty. After that, I have to run it up to the shop to have my TB adjusted. Anyways, thanks for the info guys. I sure do appreciate your help. :jeff:

06-13-2005, 02:09 PM	#9
shadow stang Registered User Join Date: Jan 2004 Location: San Antonio Posts: 218 Trader Rating: (0)	I have an appointment with CCS to get my car working right. :jeff: I go on the 25th.

06-22-2005, 11:30 AM	#10
shadow stang Registered User Join Date: Jan 2004 Location: San Antonio Posts: 218 Trader Rating: (0)	Well took a drive down to CCS on 6/18 just to see where it was at. Jim was there. I was amazed when he asked if I had time that day to get it done! I was supposed to go this Saturday the 25th. That really meant a lot to me for him to work on my car sooner. Car is running better and feels stronger than it did with the other tune. Big thumbs up to Jim. What a guy, knows his shit, and he has great customer service!! Pretty much, it was the tune I had before that was causing problems. Jim did not stop until it was fixed. I just wanted everyone to know my experience and how much I greatly appreciated his service and the work he did to my car!! Thanks Jim!!! :jeff: