Engine Dies While Driving - MAF Code, Not the MAF
06-14-2020, 12:19 PM
#61
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Member Since: Sep 2013
Location: Cape Coral, Florida
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Just back-probed the MAF signal at the ECM. The signal is absolutely rock-solid when driving, even when the engine stumbles. So, it's not the MAF wiring, either.
Opinions on the next step?
Retune this controller
Find a new controller and retune that
These damn things are as rare as hens teeth, it seems.
Opinions on the next step?
Retune this controller
Find a new controller and retune that
These damn things are as rare as hens teeth, it seems.
How did you read the MAF voltage ???...if you used a DVOM their refresh rate is to slow to see if the signal drops out !!!...best to use a graphing multimeter but a scope would be best.
06-14-2020, 08:05 PM
#62
Team Owner
Thread Starter
One of these:
https://cdn10.bigcommerce.com/s-7gav...722.1592179186
https://store.digilentinc.com/analog...-power-supply/
Same widget I used previously. Watching every rise & fall. The frequency changes as it should as the engine dies and motors down.
06-14-2020, 10:36 PM
#63
Tech Contributor
Member Since: Dec 1999
Location: Anthony TX
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
Are you 100% positive that your Ignition Switch (hot in run & start) output voltage isn't cutting out???? The only way to test it is to monitor the (hot in run & start) fuses that supply the BCM, PCM, TAC modules. If that voltage drops out, it is just like turning the engine off using the ignition switch. It wont leave ANY DTCs cause the modules think that you turned the car off.
On top of each fuse are two test slots. Measure then to ground. Remember that the BCM has MULTIPLE fuses and each one needs to be monitored.
Any of the Hot At ALL Times fuses are most likely fine.
Just my 2 cents.
Bill..
On top of each fuse are two test slots. Measure then to ground. Remember that the BCM has MULTIPLE fuses and each one needs to be monitored.
Any of the Hot At ALL Times fuses are most likely fine.
Just my 2 cents.
Bill..
06-15-2020, 07:13 AM
#64
Team Owner
Thread Starter
Are you 100% positive that your Ignition Switch (hot in run & start) output voltage isn't cutting out???? The only way to test it is to monitor the (hot in run & start) fuses that supply the BCM, PCM, TAC modules. If that voltage drops out, it is just like turning the engine off using the ignition switch. It wont leave ANY DTCs cause the modules think that you turned the car off.
On top of each fuse are two test slots. Measure then to ground. Remember that the BCM has MULTIPLE fuses and each one needs to be monitored.
Any of the Hot At ALL Times fuses are most likely fine.
Just my 2 cents.
Bill..
On top of each fuse are two test slots. Measure then to ground. Remember that the BCM has MULTIPLE fuses and each one needs to be monitored.
Any of the Hot At ALL Times fuses are most likely fine.
Just my 2 cents.
Bill..
06-28-2020, 08:42 AM
#65
Team Owner
Thread Starter
Looking like the ultimate solution is going to be a replacement ECM and a new tune. I'm thinking that a new mail-order tune may be the way to go for now in order to see if I can get the thing running reliably in the interim, and maybe do some diagnostics.
So... where to go for a mail-order? Suggestions?
~Dave
So... where to go for a mail-order? Suggestions?
~Dave
09-08-2021, 07:57 AM
#66
Drifting
