Ms2 v3.0 2.68 code. Megatune..
2JZ-NAT EDIS6 Trigger wheel.
I have been tuning my engine while driving it.. Noticed my Decel Cut light is turning on, while accelerating and in boost. Fuel is being Cut while driving. This is causing my afr's to go lean. During hard acceleration the light blips on for an instant. But on a steady highway cruise it comes on and my wideband gauge shoots up to 22.0 engine starts to stall, so I immediately let off the gas and the afr's go right down to 12.5. Engine runs normally.
I have the Decel fuel amount set at 100% in acceleration wizard, Read that this keeps fuel from being cut.
Looking for suggestions on what to try to eliminate the Decel Cut light turning on, causing Megasquirt to pull fuel. Im still researching this..
Thanks in advance
Decel Cut light coming on while cruising on freeway and accelerating
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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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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.
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Bernard Fife
- Master Squirter
- Posts: 475
- Joined: Thu Oct 29, 2009 12:54 pm
Re: Decel Cut light coming on while cruising on freeway and accelerating
dexter72,
The behaviour you see is usually due to your TPSdot threshold being too low, and as a result accel/enrichment or decel/enleanment is being triggered by noise in the TPS signal. So you will probably want to raise that parameter's value.
What you see could also be caused by the MAPdot threshold being to low, so you might need to raise that too.
There is more information on this here: http://www.megamanual.com/mt29.htm#tl
In general, posting your MSQ settings file and a datalog that illustrates the problem will get you better advice as we will be able to see what is going better on in many cases.
Lance.
The behaviour you see is usually due to your TPSdot threshold being too low, and as a result accel/enrichment or decel/enleanment is being triggered by noise in the TPS signal. So you will probably want to raise that parameter's value.
What you see could also be caused by the MAPdot threshold being to low, so you might need to raise that too.
There is more information on this here: http://www.megamanual.com/mt29.htm#tl
In general, posting your MSQ settings file and a datalog that illustrates the problem will get you better advice as we will be able to see what is going better on in many cases.
Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it.” - George Bernard Shaw
Re: Decel Cut light coming on while cruising on freeway and accelerating
Thanks Lance,
I was going through the manual and trying to find this answer, I will post a log as soon as I do one. I found a couple of posts on threads about the Tps dot and Map dot threashold. I was going to try changing it this eve but didnt get home early enough to do it.
I appreciate the response. I will repost with a log file after i make some changes and see if this is still going on..
Dexter
I was going through the manual and trying to find this answer, I will post a log as soon as I do one. I found a couple of posts on threads about the Tps dot and Map dot threashold. I was going to try changing it this eve but didnt get home early enough to do it.
I appreciate the response. I will repost with a log file after i make some changes and see if this is still going on..
Dexter
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kjones6039
- Master Squirter
- Posts: 618
- Joined: Sat Jul 22, 2006 7:02 pm
- Location: Eureka, Nevada USA
- Contact:
Re: Decel Cut light coming on while cruising on freeway and accelerating
Don't forget to post your msq along with your log, after you have made any changes.
Ken
Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
Re: Decel Cut light coming on while cruising on freeway and accelerating
Thanks kjones, Cant drive the car again until saturday morning, so i will see what happens then aftr i make the threshold changes.
Re: Decel Cut light coming on while cruising on freeway and accelerating
Thanks for the suggestions, I increased the Mapdot threshold value and the Decel Cut light is not coming on anymore during cruising or acceleration. 
Wideband readings are more steady as well.
Wideband readings are more steady as well.