A4 slipping into neutral
03-11-2013, 06:31 PM
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A4 slipping into neutral So I was driving the TA the other day, and did some WOT pulls and one time it hung in neutral between shifts so I clipped the rev limiter a bit 
Anyway I was driving it again yesterday and now it's doing it between any shift at random times and one time just slipped into neutral without a shift being needed. Any ideas what would be causing this?
Also that converter won't lock anymore once up to speed. It'll lock the first time you accelerate past 40 mph and then never again after that, and if you cruise at 60+ mph it'll just randomly come unlocked and not lock back in.
Anyway I was driving it again yesterday and now it's doing it between any shift at random times and one time just slipped into neutral without a shift being needed. Any ideas what would be causing this?Also that converter won't lock anymore once up to speed. It'll lock the first time you accelerate past 40 mph and then never again after that, and if you cruise at 60+ mph it'll just randomly come unlocked and not lock back in.
03-11-2013, 08:45 PM
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I'd look to fluid level, for intermittent shifting.
The lockup may be an immature slip code, if it gets
better after a key-cycle and then craps out again.
But the slip probably has a single cause.
The lockup may be an immature slip code, if it gets
better after a key-cycle and then craps out again.
But the slip probably has a single cause.
03-11-2013, 08:55 PM
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As Jimmyblue mentioned, the no-lockup problem is probably due to a code; scan the PCM for engine and trans codes. Let us know of any codes and we will go from there.
03-12-2013, 08:11 PM
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So you're saying it locks fine that first time but then may be throwing a fault that is not allowing converter lock up? It used to be after the car warmed up it would lock up fine, but occasionally un-lock at highway speed. Now, ever sense the neutral thing started, it's been doing the lock up once and quit.
Ok, so this code wouldn't throw a SES light? I figured all the codes would throw that light. I'll stop by Autozone and scan it, if that doesn't pick it up I was contemplating getting a copy of HPTuners soon so this will just serve as my excuse.
03-12-2013, 09:11 PM
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When I had converter problems (TCI, B&M Trick Shi(f)t
juice, bad idea) I'd get a bit of clutch flare and then the
converter would quit locking from a P1870 immature code.
This one will reset the action on every key-on and takes
several successive times to set a light.
My second converter install, sent me away a couple of
quarts low and all kinds of misbehavior, slipping, strange
shifting, etc. were the result, until I checked & filled it.
juice, bad idea) I'd get a bit of clutch flare and then the
converter would quit locking from a P1870 immature code.
This one will reset the action on every key-on and takes
several successive times to set a light.
My second converter install, sent me away a couple of
quarts low and all kinds of misbehavior, slipping, strange
shifting, etc. were the result, until I checked & filled it.
03-17-2013, 02:09 PM
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When I had converter problems (TCI, B&M Trick Shi(f)t
juice, bad idea) I'd get a bit of clutch flare and then the
converter would quit locking from a P1870 immature code.
This one will reset the action on every key-on and takes
several successive times to set a light.
My second converter install, sent me away a couple of
quarts low and all kinds of misbehavior, slipping, strange
shifting, etc. were the result, until I checked & filled it.
juice, bad idea) I'd get a bit of clutch flare and then the
converter would quit locking from a P1870 immature code.
This one will reset the action on every key-on and takes
several successive times to set a light.
My second converter install, sent me away a couple of
quarts low and all kinds of misbehavior, slipping, strange
shifting, etc. were the result, until I checked & filled it.
Ok I'll check that out, haven't gotten a chance to check the fluid yet. The car has just been sitting since last week.
I don't get any SES codes, some have speculated the clutch packs in the transmission could be going? Doesn't make much sense since it was rebuilt about 10k-15 miles ago.
03-17-2013, 03:43 PM
#7
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Primarily the 2-3 shift depends upon the weak 3-4 clutch pack.
However that would not have any effect on the 1-2 shift.
When you said "any shift", we are assuming that includes the 1-2 shift.
Take it to a trans shop to have the line pressure measured; it might be low which would give similar symptoms as low fluid level.
However that would not have any effect on the 1-2 shift.
When you said "any shift", we are assuming that includes the 1-2 shift.
Take it to a trans shop to have the line pressure measured; it might be low which would give similar symptoms as low fluid level.
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03-24-2013, 04:39 PM
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Primarily the 2-3 shift depends upon the weak 3-4 clutch pack.
However that would not have any effect on the 1-2 shift.
When you said "any shift", we are assuming that includes the 1-2 shift.
Take it to a trans shop to have the line pressure measured; it might be low which would give similar symptoms as low fluid level.
However that would not have any effect on the 1-2 shift.
When you said "any shift", we are assuming that includes the 1-2 shift.
Take it to a trans shop to have the line pressure measured; it might be low which would give similar symptoms as low fluid level.
Can you see line pressure with HPTuners? I was already mulling over getting a copy, and now is as good a time as any.
Last edited by xXSilencerXx; 03-24-2013 at 04:49 PM.
03-24-2013, 07:47 PM
#9
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NO, HP Tuners does NOT show your actual line pressure; it only (kinda) shows what the PCM is asking for, but if your trans has problems there may be little correspondence. You need a real trans pressure gauge which is only $45 on ebay.
The tune selects a pressure value between 0 and 96 which typically corresponds to a line pressure between 50 and 200psi (bit higher with a shift kit.)
Tell us your SES code and we will go from there.
The tune selects a pressure value between 0 and 96 which typically corresponds to a line pressure between 50 and 200psi (bit higher with a shift kit.)
Tell us your SES code and we will go from there.
03-26-2013, 07:22 AM
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Ok, good to know. Thanks for the help so far. Once I can get the code scanned I'll post it up. Ijust have to find a scanner or something since I can't really risk having the car get stranded trying to go to Autozone or Advance.
I'll look into the pressure gauges as well.
I'll look into the pressure gauges as well.
03-26-2013, 07:52 AM
#11
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Ok, good to know. Thanks for the help so far. Once I can get the code scanned I'll post it up. Ijust have to find a scanner or something since I can't really risk having the car get stranded trying to go to Autozone or Advance.
I'll look into the pressure gauges as well.
I'll look into the pressure gauges as well.
With a 11mm or 7/16" wrench, remove the pressure cap on the driver's side of the trans, put the right thread adapter on the hose and screw it in, not overly tight. Use tie-wraps or other method to ensure the hose doesn't touch exhaust. I tie the gauge to my outside mirror, visible from inside.
Then start the car and check the pressure. In Park/Neutral at idle, the pressure should be 50-75psi. Blip the throttle and it should jump over 150psi. Put it in Reverse and pressure should be much higher than in Park/Neutral. (With different shift kits and boost valves/springs, I've seen between 125 and 195 in Reverse at idle.)
The auto stores typically give you a free rental on the scanner after you pay the deposit, which might be $400, but fully refunded when you return it.
03-26-2013, 09:12 AM
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Search ebay for "transmission pressure gauge 5550" and select a seller; typically $40 plus shipping. The gauge includes a 6ft hose.
With a 11mm or 7/16" wrench, remove the pressure cap on the driver's side of the trans, put the right thread adapter on the hose and screw it in, not overly tight. Use tie-wraps or other method to ensure the hose doesn't touch exhaust. I tie the gauge to my outside mirror, visible from inside.
Then start the car and check the pressure. In Park/Neutral at idle, the pressure should be 50-75psi. Blip the throttle and it should jump over 150psi. Put it in Reverse and pressure should be much higher than in Park/Neutral. (With different shift kits and boost valves/springs, I've seen between 125 and 195 in Reverse at idle.)
The auto stores typically give you a free rental on the scanner after you pay the deposit, which might be $400, but fully refunded when you return it.
With a 11mm or 7/16" wrench, remove the pressure cap on the driver's side of the trans, put the right thread adapter on the hose and screw it in, not overly tight. Use tie-wraps or other method to ensure the hose doesn't touch exhaust. I tie the gauge to my outside mirror, visible from inside.
Then start the car and check the pressure. In Park/Neutral at idle, the pressure should be 50-75psi. Blip the throttle and it should jump over 150psi. Put it in Reverse and pressure should be much higher than in Park/Neutral. (With different shift kits and boost valves/springs, I've seen between 125 and 195 in Reverse at idle.)
The auto stores typically give you a free rental on the scanner after you pay the deposit, which might be $400, but fully refunded when you return it.
03-26-2013, 09:45 AM
#13
I would concur to make sure the fluid level warm is just above the cross hatch top.
Also the intermittent lockup could be engine misfire real of false and may not set a code, However low fluid level or line pressure could also be causing TCC slip to be seen causing the PCM to disable lockup.
Also the intermittent lockup could be engine misfire real of false and may not set a code, However low fluid level or line pressure could also be causing TCC slip to be seen causing the PCM to disable lockup.
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04-01-2013, 06:11 PM
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I would concur to make sure the fluid level warm is just above the cross hatch top.
Also the intermittent lockup could be engine misfire real of false and may not set a code, However low fluid level or line pressure could also be causing TCC slip to be seen causing the PCM to disable lockup.
Also the intermittent lockup could be engine misfire real of false and may not set a code, However low fluid level or line pressure could also be causing TCC slip to be seen causing the PCM to disable lockup.
HPTuners showed up today, this is what it read out.
[] P0133 - HO2S Slow Response Bank 1 Sensor 1 (SES) (Old) (History) (Current) (Immature)
[] P0135 - HO2S Heater Performance Bank 1 Sensor 1 (Immature)
[] P0300 - Engine Misfire Detected (Immature)
[] P1626 - Theft Deterrent Fuel Enable Signal Not Received (History) (Immature)
[] P1870 - Transmission Component Slipping (Old) (Immature)
Continuous Tests
Misfire: Complete
Fuel System: Complete
Comprehensive Component: Complete
Once Per Trip Tests
Catalyst: Complete
Heated Catalyst: n/a
Evaporative System: Complete
Secondary Air System: Complete
A/C System Refrigerant: n/a
Oxygen Sensor: Complete
Oxygen Sensor Heater: Complete
EGR System: Complete
04-01-2013, 06:13 PM
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I'm not sure what immature means...and that 02 sensor is a new one to me. The rears fouled a while back and I had them tuned out, but I've never had trouble with the front ones.
04-01-2013, 08:13 PM
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Ok, would that account for the incident with it feeling like it was stuck in neutral? Even if a converter is unlocked the car should still move when it's in gear if I understand how they work correctly?
As far as the misfires, could that just be a result of being a H/C car and I just need to desensitize the misfire detection a bit? Or is it more of an indication of an ill motor?
04-01-2013, 10:23 PM
#18
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Ok, would that account for the incident with it feeling like it was stuck in neutral? Even if a converter is unlocked the car should still move when it's in gear if I understand how they work correctly?
As far as the misfires, could that just be a result of being a H/C car and I just need to desensitize the misfire detection a bit? Or is it more of an indication of an ill motor?
As far as the misfires, could that just be a result of being a H/C car and I just need to desensitize the misfire detection a bit? Or is it more of an indication of an ill motor?
Unless you are really eager to pull the trans, it seems logical to to solve the engine codes first and hope for the best.
04-02-2013, 06:07 AM
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I agree that the engine codes are only consistent with no-lockup and not with it seeming to go into neutral. However if the trans really is going into neutral, that indicates a major problem and likely rebuild.
Unless you are really eager to pull the trans, it seems logical to to solve the engine codes first and hope for the best.
Unless you are really eager to pull the trans, it seems logical to to solve the engine codes first and hope for the best.
Yea I'm not super gung ho about pulling the trans right now, I'd need to gather a couple more tools to do that and set aside a weekend for it. Luckily this car is not a DD anymore so I can take my time and solve one issue at a time.
Thanks for the help in trouble shooting this so far.
