Lloyd Elliot le2 problems with car loading up and running rough
#1
Lloyd Elliot le2 problems with car loading up and running rough
Ok guys so here's what I have !
I have a 94 z28 auto and have the le2 h/c package done with all the bolt ons to compensate for the kit. So here's the issue I had the pcm tuned by Jeff Creech from Carolina auto masters and the car runs good for a little while and starts acting like it's loading up but if I punch the gas pedal down it will hesitate then clear out and then go back to running rough! Please if anyone has heard of or had this issue please help or give me an idea of what it can possibly be. Thanks a lot
I have a 94 z28 auto and have the le2 h/c package done with all the bolt ons to compensate for the kit. So here's the issue I had the pcm tuned by Jeff Creech from Carolina auto masters and the car runs good for a little while and starts acting like it's loading up but if I punch the gas pedal down it will hesitate then clear out and then go back to running rough! Please if anyone has heard of or had this issue please help or give me an idea of what it can possibly be. Thanks a lot
#2
Re: Lloyd Elliot le2 problems with car loading up and running rough
Doesn't sound like an "LE2" problem, as indicated in the topic. Sounds like a tune problem, or something in the A/F ratio control system.
Did the engine every run correctly after the tune? Or has it been a problem since day 1?
Did you ask the tuner about the problem? Did he ask you for a data log of the PCM when this problem is happening?
Is this a closed-loop tune? If so, does the problem seem to start when the PCM goes into closed loop (about 3.5 minutes from startup, coolant above 140*F and O2 sensors hot enough to work)?
Have you done basic checks, like checking for PCM codes or checking the fuel pressure?
Have you checked the rubber inlet elbow for tears, or the bottom of the elbow not being fully on the throttle body?
Has the MAF sensor been cleaned?
Did the engine every run correctly after the tune? Or has it been a problem since day 1?
Did you ask the tuner about the problem? Did he ask you for a data log of the PCM when this problem is happening?
Is this a closed-loop tune? If so, does the problem seem to start when the PCM goes into closed loop (about 3.5 minutes from startup, coolant above 140*F and O2 sensors hot enough to work)?
Have you done basic checks, like checking for PCM codes or checking the fuel pressure?
Have you checked the rubber inlet elbow for tears, or the bottom of the elbow not being fully on the throttle body?
Has the MAF sensor been cleaned?
#3
Re: Lloyd Elliot le2 problems with car loading up and running rough
Doesn't sound like an "LE2" problem, as indicated in the topic. Sounds like a tune problem, or something in the A/F ratio control system.
Did the engine every run correctly after the tune? Or has it been a problem since day 1?
Did you ask the tuner about the problem? Did he ask you for a data log of the PCM when this problem is happening?
Is this a closed-loop tune? If so, does the problem seem to start when the PCM goes into closed loop (about 3.5 minutes from startup, coolant above 140*F and O2 sensors hot enough to work)?
Have you done basic checks, like checking for PCM codes or checking the fuel pressure?
Have you checked the rubber inlet elbow for tears, or the bottom of the elbow not being fully on the throttle body?
Has the MAF sensor been cleaned?
Did the engine every run correctly after the tune? Or has it been a problem since day 1?
Did you ask the tuner about the problem? Did he ask you for a data log of the PCM when this problem is happening?
Is this a closed-loop tune? If so, does the problem seem to start when the PCM goes into closed loop (about 3.5 minutes from startup, coolant above 140*F and O2 sensors hot enough to work)?
Have you done basic checks, like checking for PCM codes or checking the fuel pressure?
Have you checked the rubber inlet elbow for tears, or the bottom of the elbow not being fully on the throttle body?
Has the MAF sensor been cleaned?
#4
Re: Lloyd Elliot le2 problems with car loading up and running rough
Did you ask the tuner about the problem? Did he ask you for a data log of the PCM when this problem is happening?
You can produce a data log of the PCM, showing what happens when the PCM transitions from open loop to closed loop. That's when the O2 sensors come into play. While the best person to look at the data log would be the tuner, there are a couple of us here that can look for problems in the system. I suspect Jeff is a reliable LT1 tuner, so it's important to look for problems in your setup .... faulty sensor(s), etc.
Go to the "sticky" in the "Computer Diagnostics and Tuning" forum, and look at the thread for Scan9495. Free download, you will need to buy a cable (ready made is best, the D-I-Y cables suffer from crappy Chinese made parts/quality control).
If you have problems downloading or getting it to run, the author of the software (GaryDoug) is a member here and is always willing to help.
You can produce a data log of the PCM, showing what happens when the PCM transitions from open loop to closed loop. That's when the O2 sensors come into play. While the best person to look at the data log would be the tuner, there are a couple of us here that can look for problems in the system. I suspect Jeff is a reliable LT1 tuner, so it's important to look for problems in your setup .... faulty sensor(s), etc.
Go to the "sticky" in the "Computer Diagnostics and Tuning" forum, and look at the thread for Scan9495. Free download, you will need to buy a cable (ready made is best, the D-I-Y cables suffer from crappy Chinese made parts/quality control).
If you have problems downloading or getting it to run, the author of the software (GaryDoug) is a member here and is always willing to help.
#5
Re: Lloyd Elliot le2 problems with car loading up and running rough
Did you ask the tuner about the problem? Did he ask you for a data log of the PCM when this problem is happening?
You can produce a data log of the PCM, showing what happens when the PCM transitions from open loop to closed loop. That's when the O2 sensors come into play. While the best person to look at the data log would be the tuner, there are a couple of us here that can look for problems in the system. I suspect Jeff is a reliable LT1 tuner, so it's important to look for problems in your setup .... faulty sensor(s), etc.
Go to the "sticky" in the "Computer Diagnostics and Tuning" forum, and look at the thread for Scan9495. Free download, you will need to buy a cable (ready made is best, the D-I-Y cables suffer from crappy Chinese made parts/quality control).
If you have problems downloading or getting it to run, the author of the software (GaryDoug) is a member here and is always willing to help.
You can produce a data log of the PCM, showing what happens when the PCM transitions from open loop to closed loop. That's when the O2 sensors come into play. While the best person to look at the data log would be the tuner, there are a couple of us here that can look for problems in the system. I suspect Jeff is a reliable LT1 tuner, so it's important to look for problems in your setup .... faulty sensor(s), etc.
Go to the "sticky" in the "Computer Diagnostics and Tuning" forum, and look at the thread for Scan9495. Free download, you will need to buy a cable (ready made is best, the D-I-Y cables suffer from crappy Chinese made parts/quality control).
If you have problems downloading or getting it to run, the author of the software (GaryDoug) is a member here and is always willing to help.
#7
Re: Lloyd Elliot le2 problems with car loading up and running rough
Ok I might need some help I've never done any scanning or stuff like that but I'm wanting to learn as pretty good at picking up on things pretty easy and what is ftp site ?
Last edited by Bignasty85; 03-02-2015 at 09:00 AM. Reason: Addition to post
#8
Re: Lloyd Elliot le2 problems with car loading up and running rough
A place where you can upload files, and other can go there and download them.
I though you might already have a file, per your comments. If it makes it easier, I'll send you my e-mail address in a Private Message, and you can e-mail the file as an attachment.
Scan9495 is better than anything else.
I though you might already have a file, per your comments. If it makes it easier, I'll send you my e-mail address in a Private Message, and you can e-mail the file as an attachment.
Scan9495 is better than anything else.
#9
Re: Lloyd Elliot le2 problems with car loading up and running rough
A place where you can upload files, and other can go there and download them.
I though you might already have a file, per your comments. If it makes it easier, I'll send you my e-mail address in a Private Message, and you can e-mail the file as an attachment.
Scan9495 is better than anything else.
I though you might already have a file, per your comments. If it makes it easier, I'll send you my e-mail address in a Private Message, and you can e-mail the file as an attachment.
Scan9495 is better than anything else.
18 injector circuit
33 map sensor circuit
43 knock sensor circuit
44 left O2 sensor circuit
48 MAF sensor circuit
50 system voltage low
65 right O2 sensor circuit
All codes saying circuit means maybe caused by faulty pcm
This is what he wrote down so I just put exactly what he said if tht might help
#11
#12
Re: Lloyd Elliot le2 problems with car loading up and running rough
The Innova has a faulty DTC code table for the 94/95 LT1 engines. It gives you about 8 codes, some of which aren't even valid, when in fact you have no codes at all. Your list is slightly different than what pops up on the Innova. Sounds like he may have used a Snap-On "brick".
I have the factory manual for the 94 F-Bodies, and am relatively familiar with all of the codes, having owned by 94 Formula for 21 years.
Scan9495 is the best thing to use. Gary has put a lot of work into making it the most useful scanner for the OBD-1 LT1's.... and he doesn't even have an LT1. It reads the PCM,l the EBCM and the air bag system. Nothing else can touch it in that respect. Well.... maybe the GM dealer Tech-1 or Tech-2, but if you want to go that route, Gary found a low $$$ Chinese clone of the Tech-1, and has found it to be fairly reliable.
I have the factory manual for the 94 F-Bodies, and am relatively familiar with all of the codes, having owned by 94 Formula for 21 years.
Scan9495 is the best thing to use. Gary has put a lot of work into making it the most useful scanner for the OBD-1 LT1's.... and he doesn't even have an LT1. It reads the PCM,l the EBCM and the air bag system. Nothing else can touch it in that respect. Well.... maybe the GM dealer Tech-1 or Tech-2, but if you want to go that route, Gary found a low $$$ Chinese clone of the Tech-1, and has found it to be fairly reliable.
Last edited by Injuneer; 03-03-2015 at 08:04 AM.
#13
Re: Lloyd Elliot le2 problems with car loading up and running rough
The alternative is that the battery supply voltage to the PCM, which dropped low enough to set the code DTC 50 (< 8.0V) tripped all those codes, because they all rely on voltage readings.
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