flucuating RPMs

GrayMatter · August 3rd, 2010, 05:01 PM

so today i hooked my Sct tuner and loaded my 91 custom race tune.
i noticed while i was idling my rpms would jump back and forth between 500 and 1000rpm. can anyone tell me why this is or if its normal?
its a 2004 auto v6

Rich J · August 3rd, 2010, 05:22 PM

I guess I will beat everyone at saying the same thing. Clean your IAC, if that don't help clean your MAF and TB.

Mr. Red Pony · August 3rd, 2010, 05:43 PM

Do you have 91 in the tank and lines?

Mr. Red Pony · August 3rd, 2010, 05:44 PM

It could be doing that if it doesn't have 91 through it. Mine did that when I got my tuner. The tank was half half with 93 and 87 on a 93 tune.

GrayMatter · August 3rd, 2010, 05:49 PM

alright thanks i'll clean them when i got off work.
and yeah it has 91 in the tank already

Mr. Red Pony · August 3rd, 2010, 05:52 PM

Have you been running 91 for a while before the tune?

GrayMatter · August 3rd, 2010, 05:59 PM

yea i was running 91 for like a week or two getting ready for the tune. and my car never idled like that before.

Rich J · August 3rd, 2010, 06:55 PM

Doesnt somewhere with the tuner or on AM or somewhere say before uploading a tune make sure you have a clean MAF, IAC, TB and such? I heard that somewhere having a dirty one of those could give some issues...

Mr. Red Pony · August 3rd, 2010, 11:17 PM

Set it to stock and see if it still does it. If not, then clean those, and re-tune.

GrayMatter · August 11th, 2010, 02:51 PM

i cleaned both the iac and maf and set it back to stock for a couple days(2) and rpms still jumped a bit but now much it threw codes P0171 P0174, I re-tuned it to 91Race and it and the CEL turned off now.

goren813 · August 11th, 2010, 06:40 PM

Tune issue not so much the IAC or other air sensors ... contact tuner, try to do some datalogging. Who did tune?

mustangmike! · August 11th, 2010, 07:00 PM

i have the same car w/ 93 tune, sometimes it will bump up like 100-200 rpm for a sec then go back to normal. But that is normal i believe tune or not. When I put my gears in I bumped my idle rpm up like 150 or so just for the hell of it

August 3rd, 2010, 05:01 PM	#1
GrayMatter Regular 2004 MustangV6 Vert Sllow Join Date: May 2010 Location: SanJoze.CA Posts: 51 iTrader: 0 reviews	flucuating RPMs so today i hooked my Sct tuner and loaded my 91 custom race tune. i noticed while i was idling my rpms would jump back and forth between 500 and 1000rpm. can anyone tell me why this is or if its normal? its a 2004 auto v6 __________________ AM CAI, Custom H-pipe, 40 flows......yea thats it..give me a couple more months And SCT 91Race Tune

August 3rd, 2010, 05:22 PM	#2
Rich J I'm doing it wrong 04 Grand Cherokee Join Date: Mar 2010 Location: South Eastern, Mass Posts: 5,211 iTrader: 0 reviews	I guess I will beat everyone at saying the same thing. Clean your IAC, if that don't help clean your MAF and TB. __________________ Formerly known as Demon_54 "I feel the same way about disco as I do about herpes." - Hunter S. Thompson

August 3rd, 2010, 05:43 PM	#3
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,789 iTrader: 10 reviews	Do you have 91 in the tank and lines? __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

August 3rd, 2010, 05:44 PM	#4
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,789 iTrader: 10 reviews	It could be doing that if it doesn't have 91 through it. Mine did that when I got my tuner. The tank was half half with 93 and 87 on a 93 tune. __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

August 3rd, 2010, 05:49 PM	#5
GrayMatter Regular 2004 MustangV6 Vert Sllow Join Date: May 2010 Location: SanJoze.CA Posts: 51 iTrader: 0 reviews	alright thanks i'll clean them when i got off work. and yeah it has 91 in the tank already __________________ AM CAI, Custom H-pipe, 40 flows......yea thats it..give me a couple more months And SCT 91Race Tune

August 3rd, 2010, 05:52 PM	#6
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,789 iTrader: 10 reviews	Have you been running 91 for a while before the tune? __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

August 3rd, 2010, 05:59 PM	#7
GrayMatter Regular 2004 MustangV6 Vert Sllow Join Date: May 2010 Location: SanJoze.CA Posts: 51 iTrader: 0 reviews	yea i was running 91 for like a week or two getting ready for the tune. and my car never idled like that before. __________________ AM CAI, Custom H-pipe, 40 flows......yea thats it..give me a couple more months And SCT 91Race Tune

August 3rd, 2010, 06:55 PM	#8
Rich J I'm doing it wrong 04 Grand Cherokee Join Date: Mar 2010 Location: South Eastern, Mass Posts: 5,211 iTrader: 0 reviews	Doesnt somewhere with the tuner or on AM or somewhere say before uploading a tune make sure you have a clean MAF, IAC, TB and such? I heard that somewhere having a dirty one of those could give some issues... __________________ Formerly known as Demon_54 "I feel the same way about disco as I do about herpes." - Hunter S. Thompson

August 3rd, 2010, 11:17 PM	#9
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,789 iTrader: 10 reviews	Set it to stock and see if it still does it. If not, then clean those, and re-tune. __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

August 11th, 2010, 02:51 PM	#10
GrayMatter Regular 2004 MustangV6 Vert Sllow Join Date: May 2010 Location: SanJoze.CA Posts: 51 iTrader: 0 reviews	i cleaned both the iac and maf and set it back to stock for a couple days(2) and rpms still jumped a bit but now much it threw codes P0171 P0174, I re-tuned it to 91Race and it and the CEL turned off now. __________________ AM CAI, Custom H-pipe, 40 flows......yea thats it..give me a couple more months And SCT 91Race Tune

August 11th, 2010, 06:40 PM	#11
goren813 MM's Official Lucifer '00 3.8L & '05 4.6L Join Date: Apr 2008 Location: Odessa, FL Posts: 3,620 iTrader: 0 reviews	Tune issue not so much the IAC or other air sensors ... contact tuner, try to do some datalogging. Who did tune? __________________ "Fast she goes...in the city of Overdose"

August 11th, 2010, 07:00 PM	#12
mustangmike! I Post Entirely Way Too Much 2004,1994,1967 14.37 @ 96 Join Date: Aug 2008 Location: Texas Posts: 6,018 iTrader: 1 reviews	i have the same car w/ 93 tune, sometimes it will bump up like 100-200 rpm for a sec then go back to normal. But that is normal i believe tune or not. When I put my gears in I bumped my idle rpm up like 150 or so just for the hell of it __________________ 227whp N/A V6 Now w/ 8th Mile 8s ! How To Jmod Your Late Model 4R70W

Remove Advertisements Sponsored Links
Ford Mustang Forum Advertisement

Threads Similar to: flucuating RPMs
Thread	Thread Starter	Forum	Replies	Last Post
RPMs?	92mustang04yfz	2.3 Mustangs	18	September 27th, 2010 09:20 PM
RPMs?	Codeman	V6 Mustangs	6	November 22nd, 2009 07:40 PM
rpms	sgrcltpunk	99-04	13	March 5th, 2008 08:39 PM
what rpms?	04Roush	99-04	9	February 5th, 2008 12:02 AM
Rpms	Mustang RacR94	99-04	9	November 23rd, 2007 10:14 PM

All times are GMT -4. The time now is 01:21 AM.
Contact Us - Modded Mustangs : Ford Mustang Forums - Privacy Statement - Top
Modded Mustangs is ©2005-2008, All Rights Reserved, And is Not Affiliated with Ford Motor Company. Forum is powered by vBulletin ©2000 - 2012, Jelsoft Ent. Ltd. & SEO by vBSEO 3.3.2 ©2009, Crawlability, Inc.