I've had the same problem for awhile and have never been able to find any leaks.
Block Learn Question
Thread Starter
Safety Car
Joined: Sep 2003
Posts: 3,598
Likes: 23
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
Block Learn Question
87 vette, 383 mini ram, custom PROM (probably the cause of my problems):
The car is running extremely rich - the plugs carbon foul very quickly. Last time I scanned it, the block learn value was 160 (integrator values also much higher than 128), indicating that the ECM "thinks" the car is running very lean, and is adding as much fuel as it can. This in turn (i believe) is causing the car to ACTUALLY run very rich, fouling the plugs.
What would cause the ECM to "think" the car is running lean, when the plugs clearly tell me it is running rich? (the answer probably lies in the PROM tuning, I just wanted to hear what you guys thought).
Thanks!!
Dan
The car is running extremely rich - the plugs carbon foul very quickly. Last time I scanned it, the block learn value was 160 (integrator values also much higher than 128), indicating that the ECM "thinks" the car is running very lean, and is adding as much fuel as it can. This in turn (i believe) is causing the car to ACTUALLY run very rich, fouling the plugs.
What would cause the ECM to "think" the car is running lean, when the plugs clearly tell me it is running rich? (the answer probably lies in the PROM tuning, I just wanted to hear what you guys thought).
Thanks!!
Dan
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Typically when the BLMs are pegged at 160, it indicates a leak - either vacuum leak after the MAF in the plenum, which introduces air into the motor that the MAF has not taken into account.
Or a leak in the exhaust from loose headers, which in turn the 02 interprets the incoming air as lean, and dumps fuel.
It could also be a BAD 02, that has died on the lean side. I would first verify that you the 02 works, which you should see it swing some, if its dead ( the millivolts are not moving) I would replace, with a heated 02. If that is working, I would bet you have a leak,,.,that is usually tougher to locate.
Or a leak in the exhaust from loose headers, which in turn the 02 interprets the incoming air as lean, and dumps fuel.
It could also be a BAD 02, that has died on the lean side. I would first verify that you the 02 works, which you should see it swing some, if its dead ( the millivolts are not moving) I would replace, with a heated 02. If that is working, I would bet you have a leak,,.,that is usually tougher to locate.
Thread Starter
Safety Car
Joined: Sep 2003
Posts: 3,598
Likes: 23
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
during the last scan, the O2 sensor voltage was definitely fluctuating properly, and the cross count # was steadily increasing.
i've tried several times to locate a vacuum leak, but haven't found anything (doesn't mean it isn't there). i even plugged off everything i could just to eliminate as many possibilities as i could. which is why i was thinking it could be the PROM tune. i don't have a lot of confidence that it was done correctly.
i've tried several times to locate a vacuum leak, but haven't found anything (doesn't mean it isn't there). i even plugged off everything i could just to eliminate as many possibilities as i could. which is why i was thinking it could be the PROM tune. i don't have a lot of confidence that it was done correctly.
Thread Starter
Safety Car
Joined: Sep 2003
Posts: 3,598
Likes: 23
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
forgot to ask:
could high knock counts (false knock counts) cause or intensify this condition? i know i am probably picking up a lot of false knock from the "rocks in a can" noise from the ZF 6 speed (w/ single mass flywheel) and other places (roller rockers, exhaust, etc.).
thanks for the help!
Dan
could high knock counts (false knock counts) cause or intensify this condition? i know i am probably picking up a lot of false knock from the "rocks in a can" noise from the ZF 6 speed (w/ single mass flywheel) and other places (roller rockers, exhaust, etc.).
thanks for the help!
Dan
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by byebyeL98
off everything i could just to eliminate as many possibilities as i could. which is why i was thinking it could be the PROM tune. i don't have a lot of confidence that it was done correctly.
Thread Starter
Safety Car
Joined: Sep 2003
Posts: 3,598
Likes: 23
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
unfortunately, i don't. 
i posted a week or two ago regarding the equipment needed to get started (laptop, cable, etc.) and received great information. i just haven't been able to find a good used laptop yet (and definitely can't afford a new one). i'll cruise e-bay this weekend and see if i can come up with something.
what software is used to retrieve the bin file from the PROM?
thanks again for your help!
i posted a week or two ago regarding the equipment needed to get started (laptop, cable, etc.) and received great information. i just haven't been able to find a good used laptop yet (and definitely can't afford a new one). i'll cruise e-bay this weekend and see if i can come up with something.
what software is used to retrieve the bin file from the PROM?
thanks again for your help!
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by byebyeL98
unfortunately, i don't.
i posted a week or two ago regarding the equipment needed to get started (laptop, cable, etc.) and received great information. i just haven't been able to find a good used laptop yet (and definitely can't afford a new one). i'll cruise e-bay this weekend and see if i can come up with something.
what software is used to retrieve the bin file from the PROM?
thanks again for your help!
i posted a week or two ago regarding the equipment needed to get started (laptop, cable, etc.) and received great information. i just haven't been able to find a good used laptop yet (and definitely can't afford a new one). i'll cruise e-bay this weekend and see if i can come up with something.
what software is used to retrieve the bin file from the PROM?
thanks again for your help!
http://cgi.ebay.com/ws/eBayISAPI.dll...771983868&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll...771510780&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll...770757445&rd=1
For software, I use Craig Moates ECM software, it will also do a dump of your PROM.
I pointed out the Toshibas because I know they will work without any issues. I have tried 3 or 4 different models of them and never had any problems.
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Thread Starter
Safety Car
Joined: Sep 2003
Posts: 3,598
Likes: 23
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
Originally Posted by Morley
Check these http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW
http://cgi.ebay.com/ws/eBayISAPI.dll...771983868&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll...771510780&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll...770757445&rd=1
For software, I use Craig Moates ECM software, it will also do a dump of your PROM.
I pointed out the Toshibas because I know they will work without any issues. I have tried 3 or 4 different models of them and never had any problems.
http://cgi.ebay.com/ws/eBayISAPI.dll...771983868&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll...771510780&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll...770757445&rd=1
For software, I use Craig Moates ECM software, it will also do a dump of your PROM.
I pointed out the Toshibas because I know they will work without any issues. I have tried 3 or 4 different models of them and never had any problems.
thanks again - i really appreciate it!! wish me luck bidding this weekend...