Wierd P1514 and a P0101
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From: Armpit of East TX
Wierd P1514 and a P0101 Here is an email I sent about this problem (copied and pasted):
'Ever since I got the computer flashed at the dealership
it's been doing this. Anytime the engine is running and you open it up, as
soon as the TB gets to WOT, it will go into limp mode. It will loose
connection with the TB, which lets it go back to rest (19% TPS). It acts
like there is nothing registering in the PCM like MAF or anything else that
makes changes because it goes way lean and won't do anything.
I have replaced the TB, so that rules that out. I will try a new TAC
controller this weekend out of another truck. I am almost starting to think
that the problem is related to tuning. Is there any way I could get you to
send me a new PCM. I'm guessing, the reason I couldn't get into that other
one is because the PCM didn't have the same serial number in it. Is there
anyway I can get the serial number out of mine and give it to you to let you
put it in the new PCM ???'
Flashing the computer at the dealership equates to getting the latest GM flash. I then edited that with a file with all the info I've worked/had worked on.
The P0101 is a little different. This one is on a hard acceleration at the top of 2nd, it kinda falls on it's face and cuts out. Doesn't turn on the SES light, but it does through the P0101 code.
When it goes WOT, it will throw a P1 and go directly into Reduced Power Mode.
Someone please help me out on this. I am stumped and ready to get my truck running right. It's a roots type blown 5.3 with a 216/220 cam in it. I think it also has my tuner stumped too.
'Ever since I got the computer flashed at the dealership
it's been doing this. Anytime the engine is running and you open it up, as
soon as the TB gets to WOT, it will go into limp mode. It will loose
connection with the TB, which lets it go back to rest (19% TPS). It acts
like there is nothing registering in the PCM like MAF or anything else that
makes changes because it goes way lean and won't do anything.
I have replaced the TB, so that rules that out. I will try a new TAC
controller this weekend out of another truck. I am almost starting to think
that the problem is related to tuning. Is there any way I could get you to
send me a new PCM. I'm guessing, the reason I couldn't get into that other
one is because the PCM didn't have the same serial number in it. Is there
anyway I can get the serial number out of mine and give it to you to let you
put it in the new PCM ???'
Flashing the computer at the dealership equates to getting the latest GM flash. I then edited that with a file with all the info I've worked/had worked on.
The P0101 is a little different. This one is on a hard acceleration at the top of 2nd, it kinda falls on it's face and cuts out. Doesn't turn on the SES light, but it does through the P0101 code.
When it goes WOT, it will throw a P1 and go directly into Reduced Power Mode.
Someone please help me out on this. I am stumped and ready to get my truck running right. It's a roots type blown 5.3 with a 216/220 cam in it. I think it also has my tuner stumped too.
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From: Armpit of East TX
Oh ... Things I have tried:
Used the tables from a known good tune, not THE tune though since it is a different segment1 ID.
Replaced TB (03 trucks are electronic throttle body)
Replaced with a known good MAF
Replaced with a known good TAC module
Increased values on the original P1514 and P0101 tables
What do the values in the P0101 table represent, mine say it is gms/sec vs gms/sec, doesn't make any sense to me.
Used the tables from a known good tune, not THE tune though since it is a different segment1 ID.
Replaced TB (03 trucks are electronic throttle body)
Replaced with a known good MAF
Replaced with a known good TAC module
Increased values on the original P1514 and P0101 tables
What do the values in the P0101 table represent, mine say it is gms/sec vs gms/sec, doesn't make any sense to me.
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From: Dallas
Flyer, I think you are talking about the Max Air ETC table when you say the P0101 table. Whoa, I went and checked Edit v1.3 and there it was DTC P0101 Allowed Error. This table has disappeared from Edit v1.4. weird. 
Anyway, my understanding of the tables is as follows:
- DTC0101 Allowed Error to me looks like gms/sec vs torque. Maybe max allowed error in gms/sec between MAF reading and some calculated airflow value (maybe from Calc Airflow table?).
- Max Air ETC appears to be the max g/cyl that the PCM will allow at a given RPM (should be gms/cyl vs RPM). It kinda looks like a VE or tq curve. I think parish had his Ethrottle closing on him at WOT due to this table. I would look at your max logged gms/cyl and multiply this table so that the peak is say 10-20% higher.
- Calculated Airflow (P1514) also looks like it might be a version of gms/cyl. Maybe gms/cyl * 1000. If you look at the 96%tps column of this table, it appears very similar to the Max Air ETC curve of g/cyl vs rpm. I would suggest making the peak value in the table about 20% higher than 1000*your highest logged g/cyl value.
I suspect perhaps this table is similar to a VE table... %tps relates to MAP, just not linearly. So this table could be plotted as MAP vs RPM if you did the %tps to MAP conversion.
Hope this helps. Good luck figuring this one out.
Anyway, my understanding of the tables is as follows:- DTC0101 Allowed Error to me looks like gms/sec vs torque. Maybe max allowed error in gms/sec between MAF reading and some calculated airflow value (maybe from Calc Airflow table?).
- Max Air ETC appears to be the max g/cyl that the PCM will allow at a given RPM (should be gms/cyl vs RPM). It kinda looks like a VE or tq curve. I think parish had his Ethrottle closing on him at WOT due to this table. I would look at your max logged gms/cyl and multiply this table so that the peak is say 10-20% higher.
- Calculated Airflow (P1514) also looks like it might be a version of gms/cyl. Maybe gms/cyl * 1000. If you look at the 96%tps column of this table, it appears very similar to the Max Air ETC curve of g/cyl vs rpm. I would suggest making the peak value in the table about 20% higher than 1000*your highest logged g/cyl value.
I suspect perhaps this table is similar to a VE table... %tps relates to MAP, just not linearly. So this table could be plotted as MAP vs RPM if you did the %tps to MAP conversion.
Hope this helps. Good luck figuring this one out.
Last edited by deezel; May 28, 2004 at 07:32 AM.
6600 rpm clutch dump of death Administrator
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From: Texas
We get 1514 errors on the Vettes since they are fly by wire. The car goes into reduced power since it sees too much air throught the MAF based on what it expects for a certain throttle position. Go look on Corvetteforum, but here is what folks are doing there.
http://forums.corvetteforum.com/zerothread?id=827311
You may want to ensure that your TPS is working correctly, and is calibrated correctly before you mod anyhting though.
http://forums.corvetteforum.com/zerothread?id=827311
With LS1-EDIT Go to ENGINE DIAGNOSTIC and click TEST PARAMETERS then click the DTC1514 table and double it. I had those issues when I modified the TB/MAF. The TB is what is doing it. The MAP sensor I believe is what the comparrison is made at by how much predicted air is supposed to be comming in.
Anyway when I ported my TB, Chris at ECS told me the fix (double that table) but I tried 150% first and it didnt work. I then doubled it and it did work. He said that it is common with FI cars or for those with MAF/TB mods..... you now fall into the latter.
-----------
P1514 Is a fail safe test for the drive by wire, Only driveby wire (vettes) have this enabled. Its a simple check to insure the driveby wire isnt going haywire.This simply uses the 1514 table and compares it to the actual MAF values. The table is Airflow (Gms/cyl)vs %tps Vs RPM. Common problem on Turbo and SC cars. Most shops will just double the values and be done with it on an big cube NA car.
------------
Bill: per our prior conversation, you may have to do more than simply scale the whole table. The reduced power events often come at small throttle openings, when the 90mm TB/intake and whatever package see much more airflow than the stock program allows. So you may well have to scale the whole table upwards and then further scale the lower throttle plate opening rows by a further ammount. This is what I had to do to gain reliability on my setup, which is similar to yours.
An alternate approach is to max the whole table: no one has posted whether that causes a different kind of error, so I've not done that.
Anyway when I ported my TB, Chris at ECS told me the fix (double that table) but I tried 150% first and it didnt work. I then doubled it and it did work. He said that it is common with FI cars or for those with MAF/TB mods..... you now fall into the latter.
-----------
P1514 Is a fail safe test for the drive by wire, Only driveby wire (vettes) have this enabled. Its a simple check to insure the driveby wire isnt going haywire.This simply uses the 1514 table and compares it to the actual MAF values. The table is Airflow (Gms/cyl)vs %tps Vs RPM. Common problem on Turbo and SC cars. Most shops will just double the values and be done with it on an big cube NA car.
------------
Bill: per our prior conversation, you may have to do more than simply scale the whole table. The reduced power events often come at small throttle openings, when the 90mm TB/intake and whatever package see much more airflow than the stock program allows. So you may well have to scale the whole table upwards and then further scale the lower throttle plate opening rows by a further ammount. This is what I had to do to gain reliability on my setup, which is similar to yours.
An alternate approach is to max the whole table: no one has posted whether that causes a different kind of error, so I've not done that.
You may want to ensure that your TPS is working correctly, and is calibrated correctly before you mod anyhting though.
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From: Armpit of East TX
Originally Posted by J-Rod
You may want to ensure that your TPS is working correctly, and is calibrated correctly before you mod anyhting though.
That's almost what it feels like though because it happens ONLY at WOT (the p1514) and will happen no other time. When it does happen it's like the TB is shut off, nothing going on with it, no movement, just a flat lined reading of 19%. The o2's start reading less than .100 and the timing drops to -2. I can put the pedal on the floor and it will go from FTC 20 to FTC 22, rpm's raise a little, and the o2's start bouncing very little.
I will try editing the tables and report back though.
6600 rpm clutch dump of death Administrator
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From: Texas
No, not necessarily.
A new TB can be wrong, is it a new stock TB, or a ported one. If its ported, then that would explain things.
But, even a new TB can have issues:
The TPS sensor could be off a bit which throws the calibration off.
You could be getting to much voltage at WOT.
These are all things you need to check with a voltmeter.
A new TB can be wrong, is it a new stock TB, or a ported one. If its ported, then that would explain things.
But, even a new TB can have issues:
The TPS sensor could be off a bit which throws the calibration off.
You could be getting to much voltage at WOT.
These are all things you need to check with a voltmeter.
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From: Armpit of East TX
It is a new stock TB, came out of a GM package. How can I check it.
It doesn't do this if the engine isn't running, That could be 2 things though, it isn't related to it being uncalibrated or the increased voltage from the altenator turning takes it over the breaking point.
It doesn't do this if the engine isn't running, That could be 2 things though, it isn't related to it being uncalibrated or the increased voltage from the altenator turning takes it over the breaking point.
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From: Armpit of East TX
Got it fixed! damn I forgot how well this thing ran! I put the whole table at 2030, I gues I need to go through and find a better value for the table,, something within reason.
Thanks soooo much for the help guys! You don't know how bad it is to have all this power on tap and not be able to use it all.
damn I forgot how well this thing ran! I put the whole table at 2030, I gues I need to go through and find a better value for the table,, something within reason. Thanks soooo much for the help guys! You don't know how bad it is to have all this power on tap and not be able to use it all.
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From: Armpit of East TX
It was impossible to drive in limp mode. The TB wouldn't move. I had to stop, get the laptop out and clear the codes. Try typing in a 12 character 9letters and numbers) password while driving down the road.
