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Irregular idle on Deceleration

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Old 12-02-2010, 10:01 PM   #81
Simon1
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Quote:
Originally Posted by hammeron View Post
you are welcome and we're all happy to help get this sorted out. i think
simon1 is on the right track with thinking about dashpot function. i've started
looking at the service manual for clues and also my advantage III help files, which
explain quite well how idle is managed. i just have to let it sink in for awhile
before i can make heads or tails of it.
I hope it is correct. Only someone with a data log or better yet a tune in hand for the car could really change it around. I am surprised Brenspeed is not wanting more datalogs and trying seperate tunes just to see.

Is the OP close enough to have a good tuner go voer his car on a dyno?

I know for a fact that there are times when Ford will send regular vehicles out to get custom tuned. Not for performance, but for drivability, fuel trims mileage, etc.

Adam Montague (owner/operator of ST Motorsports in San Bernardino) told me he was over at the Ford delaershi ona regular basis disgnosing and fixing drivability issues.
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Old 12-05-2010, 08:31 PM   #82
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Originally Posted by Simon1 View Post
I hope it is correct. Only someone with a data log or better yet a tune in hand for the car could really change it around. I am surprised Brenspeed is not wanting more datalogs and trying seperate tunes just to see.

Is the OP close enough to have a good tuner go voer his car on a dyno?

I know for a fact that there are times when Ford will send regular vehicles out to get custom tuned. Not for performance, but for drivability, fuel trims mileage, etc.

Adam Montague (owner/operator of ST Motorsports in San Bernardino) told me he was over at the Ford delaershi ona regular basis disgnosing and fixing drivability issues.


Brenspeeds attitude towards it now is "we do hundreds of these tunes every year and we see no reason why yours would be any different". and that was after I purchased another tuner from them. Their main custom tune guy Dave was fired or quit a few months ago and he was the main person helping me with it. After he left the little interest that was in my car went away.


I have had the car looked at by a shop with a tuner and a dyno but they looked over the fuel trims, o2s and how the cylinders were firing and said they looked fine. After that it didnt get looked into much more than that and I was in the process of moving so now if I want a shop to look at it I would have to find another one in my new area.
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Old 12-05-2010, 10:30 PM   #83
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Brenspeeds attitude towards it now is "we do hundreds of these tunes every year and we see no reason why yours would be any different". and that was after I purchased another tuner from them.

What did they think you were lying or something?
This is weird because Brenspeed is known for being good at
customer service.

Another thing... it should not make a difference how many tunes they do a year.
Every car is different and can react different ways to a tune.
They know this.

I really DOUBT that they have never heard of a idle issue.
In fact I KNOW they have heard of it because when I had their tune
I called them myself and asked about it.
PLUS if they did not have any idle issues they would not have a video
up on their site on cleaning the TB and it saying that was their
number one issue for idle problems.

Am I saying the problem is the tune? No.
But I am saying that it very well could be and that.
Brenspeed has a great customer service rep and I'm sorry you got with a guy
that was fired. But if I were you I would get back on the phone with them.
They seem to always be willing to help.
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Old 12-06-2010, 07:21 AM   #84
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Just be aware that Brenspeed is just one of many tuners out there. I have run a number of tunes from different tuners at this point, including Brenspeed - ALL have had the same issue. It seems our Stangs just have an inherent love to search for that perfect idle as it hunts, overshoots, and eventually decides on a spot.
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Old 12-06-2010, 08:07 PM   #85
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Quote:
Originally Posted by simplexdesign View Post
Brenspeeds attitude towards it now is "we do hundreds of these tunes every year and we see no reason why yours would be any different". and that was after I purchased another tuner from them. Their main custom tune guy Dave was fired or quit a few months ago and he was the main person helping me with it. After he left the little interest that was in my car went away.


I have had the car looked at by a shop with a tuner and a dyno but they looked over the fuel trims, o2s and how the cylinders were firing and said they looked fine. After that it didnt get looked into much more than that and I was in the process of moving so now if I want a shop to look at it I would have to find another one in my new area.
WHat should have happened is the shop should have road tested the car, not a on a dyno, and did the exact tsame thing that you are doing to cause the irregular idle. A data log, plus the tuner actually experiencing whatis going on is your surest way to fix it.

As far as Brenspeed's answer to the "we do hundreds of tunes and they are fine" is ridiculous and lazy at best. I would guess that for the most part thier tune are good enough to work properly almost all the time. But they should know that there is always that one car that causes some starnge issue and needs something tweaked.

Do you have an A/F gauge? If so what does it do when you let off the throttle and coast in gear?

Describe again what happens.

Have you pulled a vacuum line and blown into it to see if you hear a leak somewhere?

Crawled under the car and looked around?
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Old 12-06-2010, 08:42 PM   #86
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Quote:
Originally Posted by Blacksmoke View Post
What did they think you were lying or something?
This is weird because Brenspeed is known for being good at
customer service.


I really DOUBT that they have never heard of a idle issue.
In fact I KNOW they have heard of it because when I had their tune
I called them myself and asked about it.
PLUS if they did not have any idle issues they would not have a video
up on their site on cleaning the TB and it saying that was their
number one issue for idle problems.

Am I saying the problem is the tune? No.
But I am saying that it very well could be and that.
Brenspeed has a great customer service rep and I'm sorry you got with a guy
that was fired. But if I were you I would get back on the phone with them.
They seem to always be willing to help.

I don't think they think I was lying but more that they weren't too interested in finding a problem because they believed/believe their tune/intake wasn't at fault and it may prove one day that it isn't but like you said it could be.

I have dealt with another guy there his name is Chandler and he is about as useful as pointing me to the url on how to clean your TB on their site and thats about it.


Quote:
Originally Posted by Simon1 View Post
WHat should have happened is the shop should have road tested the car, not a on a dyno, and did the exact tsame thing that you are doing to cause the irregular idle. A data log, plus the tuner actually experiencing whatis going on is your surest way to fix it.

As far as Brenspeed's answer to the "we do hundreds of tunes and they are fine" is ridiculous and lazy at best. I would guess that for the most part thier tune are good enough to work properly almost all the time. But they should know that there is always that one car that causes some starnge issue and needs something tweaked.

Do you have an A/F gauge? If so what does it do when you let off the throttle and coast in gear?

Describe again what happens.

Have you pulled a vacuum line and blown into it to see if you hear a leak somewhere?

Crawled under the car and looked around?


They did do a road test at ford with it and at my old performance shop but of course on those days I couldn't get it to reproduce the problem(seems like it could be worse on colder days).


I agree every car is different and for the most part Dave was nice enough to go over my fuel trims over the phone but thats as far as he really looked into it.... And that was after I bought headers and a pro chamber from them.

All vacuum lines are good on it and underneath the car is spotless. The car is really not a daily driver as it JUST hit 30k this week.
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Old 12-07-2010, 04:15 AM   #87
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I'd take it to a shop and get it custom tuned.
That way you can just get a whole read on what is going on and be done
with it.
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Old 12-07-2010, 01:58 PM   #88
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I'd take it to a shop and get it custom tuned.
That way you can just get a whole read on what is going on and be done
with it.


Yeah I am going to ask around the forum for some good shops in my new area
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Old 12-07-2010, 11:58 PM   #89
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Quote:
Originally Posted by simplexdesign View Post
Yeah I am going to ask around the forum for some good shops in my new area
Tony at Tuners Inc. He is in Florida. Great tuner.

Used by magazines, tunes all types of car, mostly Fords. Does lots of Ford GTs and will be honest with his customer.
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Old 12-13-2010, 12:30 PM   #90
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He is a little far from me here in Tampa but I know there are a few around here I just have to get some shop names and make a few calls.
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Old 04-15-2013, 12:35 AM   #91
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Did this issue ever get solved? My 2005 GT has 52,000 miles on it and since last summer I have had sporadic idle problems. When I installed my ram air intake and would coast in neutral to a stop, it would nearly stall (multiple times a day). After running the intake for a few weeks I switched back to stock (and have been there since) and still have the issue although not as often or as dramatic. Usually now I get a stuck throttle at 1000 rpms sitting at a light or dipping to 4-500 when going from reverse to clutch in to go to 1st. I thought initially it might be my TB or TPS, so I got another one. Problem remained. I just bought another take off TB with TPS and the issue seemed to be solved for a few weeks and then about two weeks ago it started to come back. I have not checked the vacuum lines yet but here's where I am:

2005 Mustang GT 5-speed
52,000 miles
Multiple TB, MAF, and idle air tube cleanings
Battery has been replaced
Full off road exhaust with a tune to turn off rear O2's
Stock air box
Fuel filter at 40,000
HT Autolite plugs checked and re-gapped summer 2012

I do not remember the problem before the ram air intake install which was a month after the long tube install. The tune I am running now is not the stock tune. With the ram air intake installed, I did have the car fail safe a few times after WOT runs. I wonder if the dashpot tables are incorrect in the tunes since I have run the 91 octane ram air intake tune, 91 stock intake tune, and 87 stock intake tune (all by the same tuner but not custom for my car, just using known values) all with the same dropping idle problem while decelerating.

Anyone get a fix for this? I am planning to add delete plates, under drive pulleys, and the intake again and getting an actual dyno tune to see if this clears it up (but not before summer).
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Old 04-15-2013, 04:19 AM   #92
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Can the charge motion plates in the stock intake manifold cause this problem without throwing a code? I'm not entirely sure how they work, since mine have been removed for most of my cars life, but they are basically another throttle body.
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Old 04-15-2013, 06:25 AM   #93
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Subscribed! I get this problem with my 2010 GT. got the problem with Bama tunes and now with Steeda Tunes and they both told me "there is nothing wrong with the tune." Took it to the dealer and they said "there is nothing wrong with the car". Obviously, someone is incorrect.
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Old 04-15-2013, 07:23 AM   #94
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moose, I suppose it is possible that the plates are causing a problem but I think it is unlikely. I don't know much about how smooth the transition from open to closed (even though at closed they are ~45% open) is to know if the sudden closing causes stalling. Was hoping the ops before would post a solution. I'll keep this up to date. Seems to be a 4.6L issue.
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Old 04-15-2013, 08:45 AM   #95
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I had kind of the same problems when I installed my cams - hanging rpms, dipping rpms on decel and at idle, stalling, etc. Wasn't the throttle body (it isn't stock anyway). It was a tune problem - dashpot settings needed to be tweaked for more idle fuel and throttle closing rate.
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Old 04-15-2013, 11:03 AM   #96
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I had kind of the same problems when I installed my cams - hanging rpms, dipping rpms on decel and at idle, stalling, etc. Wasn't the throttle body (it isn't stock anyway). It was a tune problem - dashpot settings needed to be tweaked for more idle fuel and throttle closing rate.
My question is this: How can I convince a tuner to look into the settings, if they swear up and down there is nothing wrong with the tune? I've asked Steeda to look into the dashpot settings, and have been told "there is nothing to adjust, the tune is fine."
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Old 04-15-2013, 11:23 AM   #97
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Find a new tuner... try Tillman Speed or BrenSpeed
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Old 04-15-2013, 11:30 AM   #98
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Call Brenspeed and talk to Brent and explain what the car is doing. I am sure he can fix you right up
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Old 04-15-2013, 04:43 PM   #99
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brenspeed fixed my hanging rpms with the frpp throttle body. They didn't actual hang so much as they just took much longer to come down than the stock throttle body.
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Old 04-15-2013, 04:43 PM
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