Edge shows boost 14 PSI, it also has a map read out I will have to see what it is. When it is hot and dry outside seems to run very poorly when cool and damp runs fairly well.
Low power at low boost
- Thread starter Scarface39
- Start date
If the MAP sensor sees low pressure that doesn't match with the MAF (lookup table), it will throw a code. The smoke control/fuel limiting is almost all done on the MAF on these motors, but the baro sensor can limit things too.
It is possible your MAF sensor is intermittent, and it really did read 100 the other day, and 300 now. That could be your problem. It really sounds like you need to get someone with EFILive to get a log of your truck when it is running badly, and we can go over the hard data.
The part that gets me is you say when it is running badly, it smokes. That tells me the computer is trying to inject the right amount of fuel as if everything is fine, but something mechanical is wrong causing low power. An EFILive log will answer that, just record main fuel rate. All the diagnostics can be done with the Edge, but it is exceedingly hard to do that way.
It is possible your MAF sensor is intermittent, and it really did read 100 the other day, and 300 now. That could be your problem. It really sounds like you need to get someone with EFILive to get a log of your truck when it is running badly, and we can go over the hard data.
The part that gets me is you say when it is running badly, it smokes. That tells me the computer is trying to inject the right amount of fuel as if everything is fine, but something mechanical is wrong causing low power. An EFILive log will answer that, just record main fuel rate. All the diagnostics can be done with the Edge, but it is exceedingly hard to do that way.
Ok yesterday it wasnt smoking much at all and ran like crap, can you swap map and baro sensors out with one another, have read that there the same. What am I looking for in a normal main fuel rate?
I don't recall if the MAP and baro sensors are the same, you could look at the part number printed on them.
For main fuel rate, at idle, you want to see around 8-12 mm3 when warm (depending on if the A/C is on or off). At full throttle, it should get to around 90-92 mm3. If it never gets up that high, then the computer is limiting fueling, and we just need to figure out why. If it does go that high, the problem is probably mechanical.
For main fuel rate, at idle, you want to see around 8-12 mm3 when warm (depending on if the A/C is on or off). At full throttle, it should get to around 90-92 mm3. If it never gets up that high, then the computer is limiting fueling, and we just need to figure out why. If it does go that high, the problem is probably mechanical.
Sorry was think MAF and intake temp sensor.
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so, it does look like something is limiting fuel just need to find out what it is, might start with baro it seems that the lower the baro number the worse it runs I don't know
Okay Baro number Reads 12.6 today should read 14.7. Evidently the Baro and boost sensors cannot be interchanged ran like crap when I did swap them out. Oki artificially pumped up the Baro pressure 14.7 and it ran pretty good but still low boost at low RPM
Well never did really figure out what was limiting fueling on my lb7, got rid of edge juice and got EFI Live with dsp5 with a 486 hp hot tune and holy shit runs like a champ now . I think it had to do with timing, but I'm not a tuner who knows.