PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

need some help with idle issues on my new dyno tune.

Thread Tools
 
Search this Thread
 
Old 01-21-2009 | 08:44 PM
  #1  
bigfatls6's Avatar
Thread Starter
TECH Resident

iTrader: (34)
 
Joined: Jan 2008
Posts: 899
Likes: 0
From: Houston Tx
Default need some help with idle issues on my new dyno tune.

The car is an a4 with a circle d 4c 3800-4000 converter. I just had PRC stage 2.5 5.3 heads, 230/230 598/612 111+2 cam, Fast 92/ Jantzer 92 installed. The converter was also just installed. I had the same shop dyno tune the car also. He is the question I went to pick the car up today and drove it before leaving with it. The war would basicly try to stall or die every time you go from like park to drive or reverse or what ever. the idle would start to surge and then try to die. I also noticed when driving the car down the road you could completely let off of the gas and the car would run like 35 mph at idle like the cruise control was on set at 35mph. I also noticed when you would come to a stop the car would stay ideled up t olike 1400 rpm for like 10 seconds before it would drop down to 900 rpm like it should. Can any one give me some input on this stuff so I have an Idea of whats going on and what is causing it? I don't want the tuner to just B.S. me I want to have an Idea of whats going on.
The car dynoed 422hp and 396tq on a dyno jet. I think the air/fuel was around 12.3. The car also has pacesetter long tubes with a catted TSP y pipe and a LM1 catback no cut out and a 25% under drive pulley.
Old 01-21-2009 | 08:48 PM
  #2  
gametech's Avatar
TECH Veteran
20 Year Member
iTrader: (1)
 
Joined: Sep 2004
Posts: 4,243
Likes: 548
From: Stockbridge GA
Default

That would be completely unacceptible as a "tune". You should demand a better job or a refund. That being said, I would expect that cam to have a pretty nasty idle and some low rpm surge if the converter is locked too early.
Old 01-21-2009 | 08:57 PM
  #3  
bigfatls6's Avatar
Thread Starter
TECH Resident

iTrader: (34)
 
Joined: Jan 2008
Posts: 899
Likes: 0
From: Houston Tx
Default

Originally Posted by gametech
That would be completely unacceptible as a "tune". You should demand a better job or a refund. That being said, I would expect that cam to have a pretty nasty idle and some low rpm surge if the converter is locked too early.
I left the car with them they are supposed to be working on the tune to get it better. The tuner was not there but he kind of blamed it on the 92mm throttle body. I am just trying to get some Idea of what the problem is with the tune so if they don't get it right I can have input on the situation.
Old 01-21-2009 | 09:42 PM
  #4  
gametech's Avatar
TECH Veteran
20 Year Member
iTrader: (1)
 
Joined: Sep 2004
Posts: 4,243
Likes: 548
From: Stockbridge GA
Default

Your AFR, throttle cracker and follower settings, and your idle spark are just a few of the settings that must be adjusted. There are countless others that may not have even been touched yet.
edit-- The throttle body is NOT the main problem.
Old 01-22-2009 | 05:57 AM
  #5  
nikon1999's Avatar
10 Second Club
iTrader: (22)
 
Joined: Jul 2003
Posts: 1,289
Likes: 12
From: Wellesley, MA
Default

sounds like they gave you a WOT tune, not a drive a bility tune
Old 01-22-2009 | 07:57 AM
  #6  
bigfatls6's Avatar
Thread Starter
TECH Resident

iTrader: (34)
 
Joined: Jan 2008
Posts: 899
Likes: 0
From: Houston Tx
Default

I am hopeing they get it taken care of. I really didn't want to have to spend $400 for another dyno tune some where else.
Old 01-22-2009 | 01:20 PM
  #7  
bigfatls6's Avatar
Thread Starter
TECH Resident

iTrader: (34)
 
Joined: Jan 2008
Posts: 899
Likes: 0
From: Houston Tx
Default update

The tuner just called me and said there is a problem with my Jantzer Throttle body. He sadi the blade has too much of a gap around it causing my idles issues. I am going to get with Jantzer about it and see what he says.
Old 01-22-2009 | 03:01 PM
  #8  
moehorsepower's Avatar
TECH Addict
iTrader: (3)
 
Joined: Feb 2003
Posts: 2,334
Likes: 17
From: Texas
Default

Originally Posted by bigfatls6
The tuner just called me and said there is a problem with my Jantzer Throttle body. He sadi the blade has too much of a gap around it causing my idles issues. I am going to get with Jantzer about it and see what he says.

Uh, he didnt check the IAC counts when he was tuning? that would of told him a little something......
Old 01-23-2009 | 05:48 PM
  #9  
trophystock's Avatar
Staging Lane
 
Joined: Mar 2005
Posts: 85
Likes: 0
Default

That is probably just an excuse, I bet there is nothing wrong with your TB. If there is an issue with the TB letting to much air thru then the idle would NEVER come down and would idle high all the time. If the idle is "hanging" or the car is "running on" then there is an issue with the throttle cracker and follower, it is not the TB.
Old 01-23-2009 | 09:09 PM
  #10  
bigfatls6's Avatar
Thread Starter
TECH Resident

iTrader: (34)
 
Joined: Jan 2008
Posts: 899
Likes: 0
From: Houston Tx
Default

Originally Posted by trophystock
That is probably just an excuse, I bet there is nothing wrong with your TB. If there is an issue with the TB letting to much air thru then the idle would NEVER come down and would idle high all the time. If the idle is "hanging" or the car is "running on" then there is an issue with the throttle cracker and follower, it is not the TB.
I actually Talked with 99blancoSS who sells the Jantzer 92mm billet throttle bodies and he said there was a problem with the early design and he sent me out a new throttle body already that should be here the first part of next week hopefully. Great customer service from 99blancoSS they definetly stand behind their products. I guess we will see what happens. If they use the new throttle body as an excuse I will let them buy a Fast 92 and put on it and see what that does. Thats what they are wanting me to do right now. They guarantee that would fix all of the problems.
I do see what you are talking about though once you come to a complete stop in the car and wait a few seconds the idle will drop down t o900 rpm like it is supposed to.
Now I have another question what should be expected out of a ls1 car with a cam like I have as far as Idle surge or stalling? I have seen several cars where when you turn the A/C on it would surge and try to die Is that just poor tuning or is that to be expected? The cam I have is a 230/230 598/612 with a 111+2 It is actually a pretty mild cam except for the lobe seperation.
Old 01-23-2009 | 09:21 PM
  #11  
trophystock's Avatar
Staging Lane
 
Joined: Mar 2005
Posts: 85
Likes: 0
Default

Originally Posted by bigfatls6
I actually Talked with 99blancoSS who sells the Jantzer 92mm billet throttle bodies and he said there was a problem with the early design and he sent me out a new throttle body already that should be here the first part of next week hopefully. Great customer service from 99blancoSS they definetly stand behind their products. I guess we will see what happens. If they use the new throttle body as an excuse I will let them buy a Fast 92 and put on it and see what that does. Thats what they are wanting me to do right now. They guarantee that would fix all of the problems.
I do see what you are talking about though once you come to a complete stop in the car and wait a few seconds the idle will drop down t o900 rpm like it is supposed to.
Now I have another question what should be expected out of a ls1 car with a cam like I have as far as Idle surge or stalling? I have seen several cars where when you turn the A/C on it would surge and try to die Is that just poor tuning or is that to be expected? The cam I have is a 230/230 598/612 with a 111+2 It is actually a pretty mild cam except for the lobe seperation.
It might surge a little while in a lower gear below 1300 or so RPMs but other then that it should drive fine. I just finished a C5 with a mild 230 duration cam and I could drive around at 1200rpms in second gear and it was just fine. Go ahead and change throttle bodies but I donot think it will help and if the old one is leaking air then it might drive even worse with the new one. You need extra air for the motor and sometimes the IAC cannot supply enough. The final answer is to actually go in and tune the throttle follower and cracker, it takes some time but is really the only way to get it right.
Old 01-23-2009 | 09:38 PM
  #12  
bigfatls6's Avatar
Thread Starter
TECH Resident

iTrader: (34)
 
Joined: Jan 2008
Posts: 899
Likes: 0
From: Houston Tx
Default

The car is an auto. It didn't buck or any think like that while driving but it does have a 3800 rpm stall so that might not let it show any of that. If you let off of the gas while going down the road it would cruise at like 35 mph with out giving it any gas though. My old heads and cam car wouldn't do that and it had a torquer v.3 cam in it.
Old 01-28-2009 | 11:55 AM
  #13  
TLewis4095's Avatar
Banned
iTrader: (10)
 
Joined: Oct 2004
Posts: 1,265
Likes: 2
From: Bradenton, FL
Default

All big bore throttle bodies need an intial air reduction of anywhere from 20-70% in the tune, and on some you need to clock the TPS down app 1-2 degrees (have to ream out the mount holes and grind off the clocking tab).

Also, the throttle follower will need to be decreased.

Hope this helps.




All times are GMT -5. The time now is 02:24 AM.