dammit I am MAXING my MAF
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dammit I am MAXING my MAF Did a few ATAP runs today and lit off the MIL lamp. went into codes and found a couple of High voltage to MAF codes.
Went into freeze frame data and found I was
maxing the MAF (stock decscreened)
58.1lb/min at 6450rpm in second gear.
I didnt get this code before as my power wire to the MAF was severed. Now that it is hooked back up and working properly I am maxing it out in second gear.
What are the side effects of maxing the MAF?
What can I do about this? Does it affect my timing maps (switching to low octane etc) at all?
I dont really want to put in a ported unit as that was causing AF problems for me before. (Now I am at a nice 13:1 AF right across the board pretty much.)
Any suggestions welcome!
Thanks,
Chris
Went into freeze frame data and found I was
maxing the MAF (stock decscreened)
58.1lb/min at 6450rpm in second gear.
I didnt get this code before as my power wire to the MAF was severed. Now that it is hooked back up and working properly I am maxing it out in second gear.
What are the side effects of maxing the MAF?
What can I do about this? Does it affect my timing maps (switching to low octane etc) at all?
I dont really want to put in a ported unit as that was causing AF problems for me before. (Now I am at a nice 13:1 AF right across the board pretty much.)
Any suggestions welcome!
Thanks,
Chris
Re: dammit I am MAXING my MAF Chris
When you max the MAF, you can't deliver fuel properly. So there goes your flat 13:1 A/F <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
The 98's have a shorter MAF table than 99+, so you run into issues on extending the table. I don't recall if there is a flat lined portion of the table that can be moved up like the 99+ cars.
You can use a MAFT to shift the frequency from the sensor down, and shift the table in the PCM to match using LS1 Edit. That should let you get to the next limit of 67 lb/min and not hit the end of the table at 11250 kHz from the sensor.
When you max the MAF, you can't deliver fuel properly. So there goes your flat 13:1 A/F <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
The 98's have a shorter MAF table than 99+, so you run into issues on extending the table. I don't recall if there is a flat lined portion of the table that can be moved up like the 99+ cars.
You can use a MAFT to shift the frequency from the sensor down, and shift the table in the PCM to match using LS1 Edit. That should let you get to the next limit of 67 lb/min and not hit the end of the table at 11250 kHz from the sensor.
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Re: dammit I am MAXING my MAF </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris ARE 360:
<strong>Did a few ATAP runs today and lit off the MIL lamp. went into codes and found a couple of High voltage to MAF codes.
Went into freeze frame data and found I was
maxing the MAF (stock decscreened)
58.1lb/min at 6450rpm in second gear.
I didnt get this code before as my power wire to the MAF was severed. Now that it is hooked back up and working properly I am maxing it out in second gear.
What are the side effects of maxing the MAF?
What can I do about this? Does it affect my timing maps (switching to low octane etc) at all?
I dont really want to put in a ported unit as that was causing AF problems for me before. (Now I am at a nice 13:1 AF right across the board pretty much.)
Any suggestions welcome!
Thanks,
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Chris, you are probably just maxing it on the shift. This is not unusual with 6spd cars. Log a run through second gear up to the rev limiter without shifting. I'd guess your highest #'s will be around 44-48 lb/min. On a N/A setup with a descreened MAF, you should be nowhere near peaking, unless you are making over 550 RWHP.
Just raise the maf limit value to 14000khz
<strong>Did a few ATAP runs today and lit off the MIL lamp. went into codes and found a couple of High voltage to MAF codes.
Went into freeze frame data and found I was
maxing the MAF (stock decscreened)
58.1lb/min at 6450rpm in second gear.
I didnt get this code before as my power wire to the MAF was severed. Now that it is hooked back up and working properly I am maxing it out in second gear.
What are the side effects of maxing the MAF?
What can I do about this? Does it affect my timing maps (switching to low octane etc) at all?
I dont really want to put in a ported unit as that was causing AF problems for me before. (Now I am at a nice 13:1 AF right across the board pretty much.)
Any suggestions welcome!
Thanks,
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Chris, you are probably just maxing it on the shift. This is not unusual with 6spd cars. Log a run through second gear up to the rev limiter without shifting. I'd guess your highest #'s will be around 44-48 lb/min. On a N/A setup with a descreened MAF, you should be nowhere near peaking, unless you are making over 550 RWHP.
Just raise the maf limit value to 14000khz
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Re: dammit I am MAXING my MAF Problem is I shift at 6600 when the shiftlight comes on.
The maxing of the MAF starts at 6450rpm according to ATAP. (Unless ATAP is reading slow for some reason)
Maybe I should do a run in fourth on the highway to the 7000rpm redline and see what the MAF sensor reads then. (and pray I dont get a ticket hehe <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> )
Does the tripping of this code cause any timing map changes? Will I default to the low octane map?
Harlan how would I adjust the program in LS1 edit to compensate for setting the MAFT base setting to -15 for example?
Thanks again,
Chris
The maxing of the MAF starts at 6450rpm according to ATAP. (Unless ATAP is reading slow for some reason)
Maybe I should do a run in fourth on the highway to the 7000rpm redline and see what the MAF sensor reads then. (and pray I dont get a ticket hehe <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> )
Does the tripping of this code cause any timing map changes? Will I default to the low octane map?
Harlan how would I adjust the program in LS1 edit to compensate for setting the MAFT base setting to -15 for example?
Thanks again,
Chris
Re: dammit I am MAXING my MAF </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris ARE 360:
<strong>Does the tripping of this code cause any timing map changes? Will I default to the low octane map?
Harlan how would I adjust the program in LS1 edit to compensate for setting the MAFT base setting to -15 for example?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No and No
to match the MAFT change, you need to scale the MAF table the other way. If you go -5% on the MAFT, increase the MAF table by the same. You want to shift everything up in the PCM to match what the MAFT is feeding the PCM. That way you will see the same airflow in the PCM but at a lower frequency than w/o the MAFT. Basically, the % change outside the PCM is offset by the % change in the opposite direction inside the PCM.
<strong>Does the tripping of this code cause any timing map changes? Will I default to the low octane map?
Harlan how would I adjust the program in LS1 edit to compensate for setting the MAFT base setting to -15 for example?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No and No
to match the MAFT change, you need to scale the MAF table the other way. If you go -5% on the MAFT, increase the MAF table by the same. You want to shift everything up in the PCM to match what the MAFT is feeding the PCM. That way you will see the same airflow in the PCM but at a lower frequency than w/o the MAFT. Basically, the % change outside the PCM is offset by the % change in the opposite direction inside the PCM.
Re: dammit I am MAXING my MAF If you know the RPM when you start to hit the end of the MAF, you can richen up the mixture to compensate. Since you'll read the same airflow beyond that point you can richen up as RPM increases. To a point.
Not the best solution, but it'll work <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Not the best solution, but it'll work <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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Re: dammit I am MAXING my MAF K thanks alot guys I really appreciate it!
I will do more testing tomorrow weather permitting.
If I max out the MAF in the top of fourth I'll know it isnt shift related.
If it is maxing out I'll reduce the base of the MAFT 15% and make the change in LS1 edit like you suggested.
Thanks,
Chris
I will do more testing tomorrow weather permitting.
If I max out the MAF in the top of fourth I'll know it isnt shift related.
If it is maxing out I'll reduce the base of the MAFT 15% and make the change in LS1 edit like you suggested.
Thanks,
Chris
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Re: dammit I am MAXING my MAF You scared me their Chris.. When you posted you were seeing 58lbs for MAF rate. I was like wow...
<small>[ November 12, 2002, 12:51 AM: Message edited by: VINCE ]</small>
<small>[ November 12, 2002, 12:51 AM: Message edited by: VINCE ]</small>
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Re: dammit I am MAXING my MAF hehe if it happens at 6600rpm in third and fourth I guess Wade slipped in a solid roller/12:1 compression beast in my car when I wasnt looking <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Chris
I am hoping its shift related though hehe
I will post tomorrow if weather allows me to make a blast or two <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<small>[ November 11, 2002, 11:06 PM: Message edited by: Chris ARE 360 ]</small>
Chris
I am hoping its shift related though hehe
I will post tomorrow if weather allows me to make a blast or two <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<small>[ November 11, 2002, 11:06 PM: Message edited by: Chris ARE 360 ]</small>
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Re: dammit I am MAXING my MAF </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris ARE 360:
<strong>hehe if it happens at 6600rpm in third and fourth I guess Wade slipped in a solid roller/12:1 compression beast in my car when I wasnt looking <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Chris
I am hoping its shift related though hehe
I will post tomorrow if weather allows me to make a blast or two <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Chris if you didn't notice that "Little Change" then why don't ya pack up the beast and send it down here to TX where it'll be truly appreciated. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Good luck on getting it solved.
<strong>hehe if it happens at 6600rpm in third and fourth I guess Wade slipped in a solid roller/12:1 compression beast in my car when I wasnt looking <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Chris
I am hoping its shift related though hehe
I will post tomorrow if weather allows me to make a blast or two <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Chris if you didn't notice that "Little Change" then why don't ya pack up the beast and send it down here to TX where it'll be truly appreciated. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Good luck on getting it solved.
Re: dammit I am MAXING my MAF Chris, I have had the same problem with my car. 9 out of 10 times, the SES light will pop on when I am hitting 3rd gear at WOT. I will scan the codes and get a MAF high voltage code. I do not have edit for a-tap, so I guess I should just throw a new MAF on there?
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Re: dammit I am MAXING my MAF heheh <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I am still a hyd 360, though a badass solid roller would be nice <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'll ATAP sometime this morning and post what I find <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
thanks,
Chris
I am still a hyd 360, though a badass solid roller would be nice <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'll ATAP sometime this morning and post what I find <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
thanks,
Chris
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Re: dammit I am MAXING my MAF I tried loggin the flow rate today but ATAP crashes with an error when I try to play back. I will download the newest version and install it tonight. On a good note I cleared the codes, did a WOT run in third to 7000rpm (that was fun! <img border="0" alt="[devil]" title="" src="graemlins/gr_devil.gif" /> ) and didnt get the MAF code back again. Looks like the shift was the culprit. I will ATAP again tomorrow with the newest version of the software installed.
Cheers,
Chris
Cheers,
Chris
Re: dammit I am MAXING my MAF note on the atap problem, mine does it also, let me know if the newer version fixes it but here is what you need to do.
record like normal, when finished hit the stop button. then goto 'log', then 'open log file for playback', now open the log you just made.
if you do that it wont crash but if you just try to look at it withour reopening it it will crash and you loose the file.
record like normal, when finished hit the stop button. then goto 'log', then 'open log file for playback', now open the log you just made.
if you do that it wont crash but if you just try to look at it withour reopening it it will crash and you loose the file.