Tuner says bad converter??
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From: Commerce Twp, MI
Tuner says bad converter?? A friend of mine just put a TCI SSF 3500 stall in his '99 Z (along with a cc224/224 .581/.581 cam) and had it dyno tuned. Now he has problems with the car surging when he goes to slow down. The tuner told him the converter is not working right with the engine (doesn't allow the motor to slow the car down correctly?) and that he needs to get rid of it. He mentioned something about deceleration tables in LS1Edit I think.?.?. Has anyone had any problems like this when they installed their converters? Any ideas what my friend can do to resolve this? Any help would be greatly appreciated. Thanks in advance.
**EDIT** Oh, my friend also thinks the converter is not locking on the highway. He didn't do gears, but his revs seem higher at part throttle. Any ideas?
**EDIT** Oh, my friend also thinks the converter is not locking on the highway. He didn't do gears, but his revs seem higher at part throttle. Any ideas?
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From: Atlanta, GA
tuner suxors.
only time i surge is when i do stupid stuff like lockup at 900rpm's which is really too low.
the misfires probably causing unlocks on the freeway (see sticky at top)
go find a hptuner
and use it
only time i surge is when i do stupid stuff like lockup at 900rpm's which is really too low.
the misfires probably causing unlocks on the freeway (see sticky at top)
go find a hptuner
and use it TECH Addict
Joined: Sep 2003
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From: Atlanta, GA
and my dfco doesnt work well after the cam, i mean come on you went from a 54lb converter to a lightweight, there are going to be mass changes that will effect things.
do a search on "cruise control" in this forum and you'll see your not alone...
(now tci is good but yah there could be a problem with it, but im guessing if the dude is trying to deal with dfco he needs to show some logs)
do a search on "cruise control" in this forum and you'll see your not alone...
(now tci is good but yah there could be a problem with it, but im guessing if the dude is trying to deal with dfco he needs to show some logs)
Run, do not walk, to a qualified tuner. The TCI should be lighter than stock and a little looser. This requires the tuner to fine tune the IAC through the amount of TB air and IAC settings & timing. If they can't do this on a 224 cam; they should not be anywhere near your car.
Converter may unlock on the highway if the random misfires code was not turned off. Did they missed this too?
Converter may unlock on the highway if the random misfires code was not turned off. Did they missed this too?
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Joined: Sep 2003
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From: Atlanta, GA
I've found there are great m6 tuners but the finesse and road tuning necessary for an A4 is quite a bit more. Not to say the tuner isn't great, but sometimes they need more experience or road-time to get an a4 right.
Of course that isn't always profitable now is it?
Of course that isn't always profitable now is it?
I have an excellent tuner. My car was idle stable with a Midwest "tight" feeling 4000 stall. Put in a PT4400 and my car surges coming to stops. He has made it better but hasn't had much time with it. I also have no lock up - for sure, but attribute that directly to the converter. It either never had it or it's gone now! Bought it used.
I don't mind no lock up but it does keep the rpms around 3000 cruising when before it would lock down to 2300 or so. I rather enjoy the revs right where power is!
And no pesky lock/unlock at part throttle. It's old school flash and go like this!
As far as surge - yup, lots of converter guys get it from the weight change on the crank. Some get tuned out, some live with a small amount.
I'll get mine tuned out but it's not hard to hold the tach at 1300 coming to a light until stopped. I have no "cruise control" issues while driving. Hope this helps.
I don't mind no lock up but it does keep the rpms around 3000 cruising when before it would lock down to 2300 or so. I rather enjoy the revs right where power is!
And no pesky lock/unlock at part throttle. It's old school flash and go like this!
As far as surge - yup, lots of converter guys get it from the weight change on the crank. Some get tuned out, some live with a small amount.
I'll get mine tuned out but it's not hard to hold the tach at 1300 coming to a light until stopped. I have no "cruise control" issues while driving. Hope this helps.
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From: Arlington, TX Congestion City
If you have no lock up at all then I beg to differ with the statement about you having an excellent tuner. My PT4000 locks @ 40 MPH everytime. Locks on highway with no issues. Bought mine used too. Guy sprayed the **** out of it. I've had no issues since installation 10K ago.
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The lighter rotating mass is more of a challenge to get
stable against the IAC's natural loop frequency I believe,
things that affect idle loop response have to be tuned
tighter. That's all. It's a normal tendency, and if the
guy wants to blame the hardware instead of tuning then
I'd drive off before he gets a chance to demonstrate the
total extent of his ignorance. But I guess it's a bit late
for that. Before throwing any more money at this "pro"
though, your buddy ought to check out the option of
doing it hisself next time, with HPTuners (or other but
I don't expect he'll find anything close). If the price is
too much he could find another couple of '99 F-body
dudes and form a syndicate.
Dyno tuning does not come anywhere close to exercising
the A4 operating envelope.
stable against the IAC's natural loop frequency I believe,
things that affect idle loop response have to be tuned
tighter. That's all. It's a normal tendency, and if the
guy wants to blame the hardware instead of tuning then
I'd drive off before he gets a chance to demonstrate the
total extent of his ignorance. But I guess it's a bit late
for that. Before throwing any more money at this "pro"
though, your buddy ought to check out the option of
doing it hisself next time, with HPTuners (or other but
I don't expect he'll find anything close). If the price is
too much he could find another couple of '99 F-body
dudes and form a syndicate.
Dyno tuning does not come anywhere close to exercising
the A4 operating envelope.
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Verdad Gallardo JUST TO BE CLEAR ON MY STATEMENTS:
My tuner has had great success getting my previous 2 converters to idle without surge. The used PT4400 has been more of a challenge mostly because I have not left him the car and we tried about 2 things in 2 drives.
As far as lock up not occuring in MY APPLICATION - it IS the converter.
I pulled out a Midwest 4000 2.5 str that locked up too much in my liking. Never bothered to tune because it was too tight as well.
Put in the used PT4400 (if that's what it is) with NO OTHER CHANGES. And the flash is great, I love the loose feel, but it never, ever locked up since installation. Checked the tune and we tried extreme lock up methods without any change on the street. My converter will not lock up. Nothing to do with my tuner. Swapping converters without any tuning I should not loose lock up completely, and I did. CONVERTER.
I wanted to share the idle surge and loss of lock up story for the original posting member to read. We all agree the lighter converter causes surge. We should all agree surge can be tuned out. I am unsure what the other members lock up issue is.
My tuner has had great success getting my previous 2 converters to idle without surge. The used PT4400 has been more of a challenge mostly because I have not left him the car and we tried about 2 things in 2 drives.
As far as lock up not occuring in MY APPLICATION - it IS the converter.
I pulled out a Midwest 4000 2.5 str that locked up too much in my liking. Never bothered to tune because it was too tight as well.
Put in the used PT4400 (if that's what it is) with NO OTHER CHANGES. And the flash is great, I love the loose feel, but it never, ever locked up since installation. Checked the tune and we tried extreme lock up methods without any change on the street. My converter will not lock up. Nothing to do with my tuner. Swapping converters without any tuning I should not loose lock up completely, and I did. CONVERTER.
I wanted to share the idle surge and loss of lock up story for the original posting member to read. We all agree the lighter converter causes surge. We should all agree surge can be tuned out. I am unsure what the other members lock up issue is.
Last edited by chief455; Sep 10, 2004 at 06:30 PM.
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From: Chicago Far Far South Subs
I have the same cam but a 3200 Vig stall. I had the same problem with the surging but my TC locked as it is suppose to.
Who ever mentioned the IAC loop hit it on the head................................
In my case I had a ported/polished and epoxied TB. The problem with my surging was that the hole for the IAC through the TB was to small 1/4",, I drilled it out to 1/2" and it smoothed the surge almost completely. I had my tuner raise the idle from 700 to 800 and it cured it completely.
The IAC (stock tuning) can not keep up with the light weight TC so it has to hunt to get there and if anything is disturbed, like in my case, then it wont respond right.
I thought this may help since it is a differant view point of the prob.
Good luck
Dave
Who ever mentioned the IAC loop hit it on the head................................
In my case I had a ported/polished and epoxied TB. The problem with my surging was that the hole for the IAC through the TB was to small 1/4",, I drilled it out to 1/2" and it smoothed the surge almost completely. I had my tuner raise the idle from 700 to 800 and it cured it completely.
The IAC (stock tuning) can not keep up with the light weight TC so it has to hunt to get there and if anything is disturbed, like in my case, then it wont respond right.
I thought this may help since it is a differant view point of the prob.
Good luck
Dave
Originally Posted by Farmer2
I have the same cam but a 3200 Vig stall. I had the same problem with the surging but my TC locked as it is suppose to.
Who ever mentioned the IAC loop hit it on the head................................
In my case I had a ported/polished and epoxied TB. The problem with my surging was that the hole for the IAC through the TB was to small 1/4",, I drilled it out to 1/2" and it smoothed the surge almost completely. I had my tuner raise the idle from 700 to 800 and it cured it completely.
The IAC (stock tuning) can not keep up with the light weight TC so it has to hunt to get there and if anything is disturbed, like in my case, then it wont respond right.
I thought this may help since it is a differant view point of the prob.
Good luck
Dave
Who ever mentioned the IAC loop hit it on the head................................
In my case I had a ported/polished and epoxied TB. The problem with my surging was that the hole for the IAC through the TB was to small 1/4",, I drilled it out to 1/2" and it smoothed the surge almost completely. I had my tuner raise the idle from 700 to 800 and it cured it completely.
The IAC (stock tuning) can not keep up with the light weight TC so it has to hunt to get there and if anything is disturbed, like in my case, then it wont respond right.
I thought this may help since it is a differant view point of the prob.
Good luck
Dave
thanks for factual input
Too much misfire will prevent TCC lockup, and lighter
smaller converters are prone to detect more misfires
(misfire is crankshaft jerk and lighter weight / smaller
diameter makes more, even with the same amount of
torque ripple). I would have a look at the misfire counts
in driving or on dyno and set the misfire detect limit to
something above what you see as "peak normal". Some
people just set up to 32000 but that eliminates the
intended drivetrain protection (soft coupled better than
hard coupled if the crank is doing a lot of jerking).
smaller converters are prone to detect more misfires
(misfire is crankshaft jerk and lighter weight / smaller
diameter makes more, even with the same amount of
torque ripple). I would have a look at the misfire counts
in driving or on dyno and set the misfire detect limit to
something above what you see as "peak normal". Some
people just set up to 32000 but that eliminates the
intended drivetrain protection (soft coupled better than
hard coupled if the crank is doing a lot of jerking).
