Open Loop Problem??
#1
Launching!
Thread Starter
iTrader: (13)
Join Date: May 2002
Location: Niles, Michigan
Posts: 238
Likes: 0
Received 0 Likes
on
0 Posts
Open Loop Problem??
I have a problem I've been struggling with for a few months. When I start the car it smokes, runs extremely rich, sounds like its not hitting all cylinders, pops through the exhaust and has no power. It all goes away when it warms up. Usually after driving a mile or so. I assume the car is in open loop during this time. MTI programmed the car a few years ago and nothing has changed since. So far I have done the following.
only engine code I get is 1637 Alternator L-terminal
put in new plugs, and 02 sensors.
I'm struggling with this issue. Anyone have any suggestions on where to look or what to try? I do have autotap.
When in open loop what sensors is the pcm reading? I think thats where I should start..????
only engine code I get is 1637 Alternator L-terminal
put in new plugs, and 02 sensors.
I'm struggling with this issue. Anyone have any suggestions on where to look or what to try? I do have autotap.
When in open loop what sensors is the pcm reading? I think thats where I should start..????
Last edited by TAGOES11S; 07-16-2007 at 12:57 PM.
#2
TECH Addict
iTrader: (10)
Join Date: Jun 2004
Location: Commerce Twp, MI
Posts: 2,918
Likes: 0
Received 0 Likes
on
0 Posts
The MAF is mainly responsible for fueling. However, the IAT, ECT, and MAP sensors can influence fueling some.
I'd try to find someone with a WBO2 and log a cold start with your scanner. Look for differences in commanded AFR and actual AFR, check where the spark is at, and check what the IAC is doing.
Chances are it's mechanical though if this just started happening all of the sudden.
I'd try to find someone with a WBO2 and log a cold start with your scanner. Look for differences in commanded AFR and actual AFR, check where the spark is at, and check what the IAC is doing.
Chances are it's mechanical though if this just started happening all of the sudden.
#4
Launching!
Thread Starter
iTrader: (13)
Join Date: May 2002
Location: Niles, Michigan
Posts: 238
Likes: 0
Received 0 Likes
on
0 Posts
Is there a way I can force it to stay in open loop why I check items out? I have another LS1 that I can actually swap MAF, MAP sensors, etc to try to find the problem.
#5
TECH Resident
iTrader: (3)
Originally Posted by TAGOES11S
Is there a way I can force it to stay in open loop why I check items out?
#6
Launching!
Thread Starter
iTrader: (13)
Join Date: May 2002
Location: Niles, Michigan
Posts: 238
Likes: 0
Received 0 Likes
on
0 Posts
I don't have easy access. I think the closest tuner is 2hrs away. Or is this something any shop with a good scanner could do a diagnostic on? I planned on taking the car in for a dyno tune, but didn't think they would want to spend the time trying to figure this problem out.
Last edited by TAGOES11S; 07-16-2007 at 02:52 PM.
#7
FormerVendor
iTrader: (9)
Join Date: May 2003
Location: Jacksonville, Fl
Posts: 1,573
Likes: 0
Received 0 Likes
on
0 Posts
The generator code is completely seperate from the OL fueling issue but needs to be addressed as well. In plain English, your alternator is not putting out enough juice for the total load of the vehicle's demand.
When the car is in OL you are not running off of your O2's and the tune needs to be calibrated.
When the car is in OL you are not running off of your O2's and the tune needs to be calibrated.