Need Help w/Data
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Need Help w/Data
Using Datamaster, I've driven my car around looking at some data and have a few questions. This is a 1993 383 LT1 6spd Coupe.
Spark Advanace varies from 30 to 40 degrees on average. This ok? Seems high? Or is it low?
It ran for closed loop for a few seconds and then switched to open loop. Which one is which. Is closed loop going off sensor data or is it the other way around.
At idle(~1000rpm), the Map sensor is reading 12.86 "Hg, does that sound right?
I've been having some running issues. Backfiring, stalling when trying to idle, rough accel and I'm trying to pinpoint the problem. Ignition is good, motor is new, so I'm figuring it's in the programming somewhere.
P.S. I'm running a chip from PCMForless.
Spark Advanace varies from 30 to 40 degrees on average. This ok? Seems high? Or is it low?
It ran for closed loop for a few seconds and then switched to open loop. Which one is which. Is closed loop going off sensor data or is it the other way around.
At idle(~1000rpm), the Map sensor is reading 12.86 "Hg, does that sound right?
I've been having some running issues. Backfiring, stalling when trying to idle, rough accel and I'm trying to pinpoint the problem. Ignition is good, motor is new, so I'm figuring it's in the programming somewhere.
P.S. I'm running a chip from PCMForless.
Racer
Joined: Jun 2000
Posts: 469
Likes: 0
From: Norfolk VA
Re: Need Help w/Data (kman0066)
Hello, the spark advance looks ok. Closed loop is where the vehicle uses the O2 sensors and the long and short term BLM's to correct the fueling while on the fly. If your car is going into closed loop and then coming back out it is not normal. How are your O2 sensors? Your MAP seems a little low, but I may be wrong. WRT the backfiring and such, I am not a fan of mail order tunes.
RJ
[Modified by HJV11, 6:27 AM 6/4/2004]
[Modified by HJV11, 6:27 AM 6/4/2004]
RJ
[Modified by HJV11, 6:27 AM 6/4/2004]
[Modified by HJV11, 6:27 AM 6/4/2004]
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Need Help w/Data (HJV11)
Right, I'm not counting on the mail-order chip to give me everything, but I was hoping it would run good enough to make sure all my equipment was working as it should before I take it to a dyno to get it properly tuned.
I'll check into my 02 sensors, I was noticing only one seemed to be fluctuating. I'll get back after I check out the o2 sensors. Still though, full thorttle can be quirky too, well, later.
I'll check into my 02 sensors, I was noticing only one seemed to be fluctuating. I'll get back after I check out the o2 sensors. Still though, full thorttle can be quirky too, well, later.
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: (scorp508)
Well, I replaced the o2 sensors and it runs much better. Still though, it trys to die at idle and with A/C on, it does die. Cruising at low rpms also creates an unstable feel to the power.
I'm trying to think of what I told PCMforless to tune it with. I was planning on getting a 52mm throttle body so do think that if someone tuned for a 52mm throttle body it would create idle problems for using a 48mm(stock) TB. I still plan on getting the 52mm TB but for now I'd like to find the problem before buying more perf. parts. If I had to say something, I'd say it's running rich at idle, and everywhere else for that matter. I get a bit of fuel smoke on startup and full throttle. I'm sure it's fuel.
I'm trying to think of what I told PCMforless to tune it with. I was planning on getting a 52mm throttle body so do think that if someone tuned for a 52mm throttle body it would create idle problems for using a 48mm(stock) TB. I still plan on getting the 52mm TB but for now I'd like to find the problem before buying more perf. parts. If I had to say something, I'd say it's running rich at idle, and everywhere else for that matter. I get a bit of fuel smoke on startup and full throttle. I'm sure it's fuel.
Racer
Joined: Mar 2002
Posts: 498
Likes: 21
From: Maine
Re: Need Help w/Data (kman0066)
Can you post your Datamaster log(s) so we can look at them. BTW I had a PCMFORLESS chip and it was horrible. My advice would be to invest in the equipment/software and learn to tune it yourself.
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Need Help w/Data (kman0066)
Alright, I have a log to send, now how do I post it? Or should I just e-mail it to who will look at it?
Lets try this, http://colingast.tripod.com/forumtest.uni
Alright, it worked, right click, save target as, then save to a .uni file rather than a html file.
Not the three full throttle runs towards the end. The first one the traction control hit because I forgot to turn it off, hence the 100%, 0%, 100% throttle fluctuations. However, that time it felt like the engine had just gained double the horspower. The next 2 runs it felt like the engine was bucking and bogging and I couldn't even get it to the 6400 rpm redline.
I have noticed one problem I need to fix, the EGR is still working, I need to get that turned off since I don't have it, unless it's taking air from the AIR system which is still hooked up.
[Modified by kman0066, 5:04 PM 6/10/2004]
[Modified by kman0066, 5:12 PM 6/10/2004]
Lets try this, http://colingast.tripod.com/forumtest.uni
Alright, it worked, right click, save target as, then save to a .uni file rather than a html file.
Not the three full throttle runs towards the end. The first one the traction control hit because I forgot to turn it off, hence the 100%, 0%, 100% throttle fluctuations. However, that time it felt like the engine had just gained double the horspower. The next 2 runs it felt like the engine was bucking and bogging and I couldn't even get it to the 6400 rpm redline.
I have noticed one problem I need to fix, the EGR is still working, I need to get that turned off since I don't have it, unless it's taking air from the AIR system which is still hooked up.
[Modified by kman0066, 5:04 PM 6/10/2004]
[Modified by kman0066, 5:12 PM 6/10/2004]
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Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Need Help w/Data (kman0066)
Driving around more, it really has a large flat spot in the upper rpms, starting at 4500-5000rpms. Before that, it feels like the car is about to take off, at 5k rpms, it feels like I am pulsating the throttle right above idle. So, here comes the plea, anybody out there with a 383 and LT4 hot cam copy a chip for me? I'll pay for your troubles. I need the EGR turned off as well since it is not hooked up.
I'd really like to see the car run well before I take it to a dyno for proper tuning. I don't see how anything else could be wrong, but spending a large deal of money on the dyno to find out that it's something else would suck.
I'd really like to see the car run well before I take it to a dyno for proper tuning. I don't see how anything else could be wrong, but spending a large deal of money on the dyno to find out that it's something else would suck.
Thread Starter
Burning Brakes
Joined: May 2000
Posts: 1,160
Likes: 10
From: Nashville TN
Re: Need Help w/Data (93Blackrose)
Eh, it's not like I have wideband o2 sensors anyways. The engine appears to be running fine other than the EGR trying to work when it can't since there is no tube. The problem I'm sure lies in that it is running too rich or lean at high rpms. It's weird though, it feels like I'm hitting a temporary rev limiter at 5k+ rpms. I actually made it to 6k today but I don't want to do it again, it really didn't seem to want to get there.
One question though, the injector DC reaches 105 at certain points, what is that? Didn't the injectors could go past 100%, is this a problem?
As to the file(did you save it as a .uni file?) It automatically saves as a .htm file for some reason if you don't specify when saving.
[Modified by kman0066, 11:02 PM 6/12/2004]
One question though, the injector DC reaches 105 at certain points, what is that? Didn't the injectors could go past 100%, is this a problem?
As to the file(did you save it as a .uni file?) It automatically saves as a .htm file for some reason if you don't specify when saving.
[Modified by kman0066, 11:02 PM 6/12/2004]