I am haveing a problem with the afr going very lean while driving. I have the EGO correction off and am trying to tune. What happens is that the motor will start running rough and cutting out. The afr goes very lean and I see that the PW goes up a lot. I was looking at a datalog and saw that when the afr goes really lean and the PW goes up there is a drop off on the IAC counts from the 250 that I should have at running temp to 150. I think that this is causing the lean condition and the PW goes up to try to compensate for the beg jump in the MAP reading. What would cause the IAC to make this jump and then correct itself?
Look around 1485.
Also there seem to be some strange spikes in the VBAT. Thanks. Billk
IAC making the afr go way lean
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Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0). For tuning/troubleshooting questions, please attached a datalog and your MSQ file to your post.
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The full forum rules are here: Forum Rules, be sure to read them all regularly.
Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0). For tuning/troubleshooting questions, please attached a datalog and your MSQ file to your post.
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
The full forum rules are here: Forum Rules, be sure to read them all regularly.
IAC making the afr go way lean
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MSII V3 board, 2.891 revision, 330 inch '56 Desoto Hemi in a '50 Mercury. 350 Chevy throttle body. Stepper IAC. Innovate wide band O2.
Re: IAC making the afr go way lean
I can't load the datalog because it is too large. Is there a way to cut back the datalog size by chopping off some of the early or late parts? Billk
MSII V3 board, 2.891 revision, 330 inch '56 Desoto Hemi in a '50 Mercury. 350 Chevy throttle body. Stepper IAC. Innovate wide band O2.
Re: IAC making the afr go way lean
Strangely, I have not seen the problem again. ??? Billk
MSII V3 board, 2.891 revision, 330 inch '56 Desoto Hemi in a '50 Mercury. 350 Chevy throttle body. Stepper IAC. Innovate wide band O2.