locking/unlocking NOT from misfire
locking/unlocking NOT from misfire Performabuilt Stage 2 4L60E w/ billet 2800 stall. It has less than 1000 miles on it so far. I was driving from Jacksonville to Tampa and it started to unlock on me. I have disabled misfire detection through HP Tuners (maxed the tables, and increased the temperature requirement so high that it won't turn misfire detection on).
Tranny temp was not high, and no misfires were detected when I was scanning it. Performabuilt said that a TPS sensor could cause that, so would that show up on the scan? I attached one of the scans. At time 24.36.261 it unlocks. In the other file it unlocks around 15.53, and there is no misfire detected. Please advise.
Also, if I need to be scanning with different parameters, please let me know. My PCM is a 98 though, so I'm limited to the 24bits...
Tranny temp was not high, and no misfires were detected when I was scanning it. Performabuilt said that a TPS sensor could cause that, so would that show up on the scan? I attached one of the scans. At time 24.36.261 it unlocks. In the other file it unlocks around 15.53, and there is no misfire detected. Please advise.
Also, if I need to be scanning with different parameters, please let me know. My PCM is a 98 though, so I'm limited to the 24bits...
yeah im serious, mine would do that **** and i changed the solenoid and chased all kinds of stuff trying to figure it out. turns out the switch on the brake pedal was close enough if i hit a bump just so it would trip. worst was washboards on gravel! on-off-on-off constantly. I had recently had the brakes unhooked and the air in the lines let the pedal drop some
When I first read your response I thought you were just being sarcastic. Then I thought about it and it actually makes sense.
I did notice it unlock when I hit some bumps a couple of times. Not every time, but once or twice. That'd be nice if that's what my problem is
*fingers crossed*
I did notice it unlock when I hit some bumps a couple of times. Not every time, but once or twice. That'd be nice if that's what my problem is
*fingers crossed*
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If it's an aftermarket converter with a higher stall, it will have a different rotational mass than the stock stall, and the pcm detects this as misfire (something like that from what I've read on here).
Anyone with a flash tuning program can take care of it for you by maxing out the values for misfire detection in the PCM.
Anyone with a flash tuning program can take care of it for you by maxing out the values for misfire detection in the PCM.
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Verdad Gallardo Grr: if it's the brake pedal switch, wouldn't cruise control disengage? I haven't tightened the pedal, but I experimented with it today. I was on the highway (it seems to unlock only at higher speeds) and had cruise engaged. I placed my left foot under the brake pedal and held it up for 5-10min until the converter unlocked. Cruise stayed engaged and my foot/the pedal hadn't dropped any.
I did notice though that when I turn my AC on (before the compressor even engages) that all of my gauges will jump, so I think I have a ground loose. I also noticed my speedometer ticking with my blinker today.... You think that could be a cause of the problem?
I did notice though that when I turn my AC on (before the compressor even engages) that all of my gauges will jump, so I think I have a ground loose. I also noticed my speedometer ticking with my blinker today.... You think that could be a cause of the problem?
yes thats likely, just the other day i had the main power wire to the starter burn on the header, it was fine just driving but if I got over 30% throttle the whole car would cut out, guages would sweep, etc. took about 3 hours to figure that one out. it is definately electrical if its doing as you describe
Real-time lock-ublock-lock is misfires or maybe electrical.
But unlock and stay unlocked could also be an immature
slip code, like from the converter not being given enough
line to hold tight.
But unlock and stay unlocked could also be an immature
slip code, like from the converter not being given enough
line to hold tight.
Well, I found the loose ground 
It was on the passenger side. It didn't seem too loose, but it was enough to be tightened, and now my gauges are acting normal again. I haven't had a chance to drive it on the highway again yet.
By "lock and stay unlocked," you mean like unlocked for 5min or so? B/c when it acted up the past few times it would stay unlocked for only 9 seconds or so, then lock again. I'll get some highway driving in tomorrow, but not much. I'll post up what happens *fingers crossed*
And thank you for the responses so far guys.
It was on the passenger side. It didn't seem too loose, but it was enough to be tightened, and now my gauges are acting normal again. I haven't had a chance to drive it on the highway again yet.By "lock and stay unlocked," you mean like unlocked for 5min or so? B/c when it acted up the past few times it would stay unlocked for only 9 seconds or so, then lock again. I'll get some highway driving in tomorrow, but not much. I'll post up what happens *fingers crossed*
And thank you for the responses so far guys.
Thats exactly what mine is doing.I just bought HPtuners now I just have to figure out how to use it.
Performabuilt Stage 2 4L60E w/ billet 2800 stall. It has less than 1000 miles on it so far. I was driving from Jacksonville to Tampa and it started to unlock on me. I have disabled misfire detection through HP Tuners (maxed the tables, and increased the temperature requirement so high that it won't turn misfire detection on).
I set Min ECT to 284, Max ECT to 0.
I did nothing with the tables.
I also set lockup speed to 55 mph 4th only. 12.5% TPS. Unlock to 50. Works perfect now.
Mine has less than 500 miles on it, I just got the car running.
I contacted Performa to ask about the PWM settings since they disable this feature internally. I have gotten no response in 5 days. Frank used to reply pretty promptly. I wonder what is up with that?
With the B&M cooler I'm running, I have yet to see trans temps above 160, even with 90+ ambient.
Ron
Well, I drove for about 20min on the highway today, and it didn't unlock once 
So I think that lose ground may've been the culprit. I'm still trying to not get my hopes up too quick though.
RonSSNova: What kind of gear are you running in the rear? I have 3.73s and mine is currently set to lock & unlock at 40mph, depending on the throttle amount. When it 1st locks it at 40mph it will sometimes bog, but only for a moment. Usually I'm too into the throttle for it to lock at 40mph though
Have you tried calling Frank again? I always seemed to get a prompt reply. I'm running the cooler that came with the tranny, but I saw the temp get up to 200 at one point. I'm wondering if it'd be a good investment to buy a larger one when I get some funds.
Swoop: if it's the TPS sensor, wouldn't that show a change on the VCM Scanner when data logging?
01wss6: ? You mean if you are cruising and the converter is locked, then you let off the gas it will unlock (like it should). But when you apply throttle again it won't lock up unless you tap the brake???
So I think that lose ground may've been the culprit. I'm still trying to not get my hopes up too quick though. RonSSNova: What kind of gear are you running in the rear? I have 3.73s and mine is currently set to lock & unlock at 40mph, depending on the throttle amount. When it 1st locks it at 40mph it will sometimes bog, but only for a moment. Usually I'm too into the throttle for it to lock at 40mph though
Have you tried calling Frank again? I always seemed to get a prompt reply. I'm running the cooler that came with the tranny, but I saw the temp get up to 200 at one point. I'm wondering if it'd be a good investment to buy a larger one when I get some funds.
Swoop: if it's the TPS sensor, wouldn't that show a change on the VCM Scanner when data logging?
01wss6: ? You mean if you are cruising and the converter is locked, then you let off the gas it will unlock (like it should). But when you apply throttle again it won't lock up unless you tap the brake???
That's kind of like saying "There is a solution to your problem, but that's all I'm going to share"
For future reference, what would they be? I have HPTuners, so I use that scanner. Are they custom PIDS that you input, or default ones? Before I found the loose ground I logged misfire counts, TTC Mode, and Slip Rpm. I didn't see a line pressure one. Info is appreciated
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Joined: Apr 2002
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From: So.Cal.
they are standard GM-provided pids (can be seen by OTC, Tech2, AE, others); line pressure is there also (but it may be called something else);
since I've never used HPT I wouldn't know if it supports those pids... why don't you fire it up and take a look.