Installed Procharger, now surging in lower rpms
12-09-2013, 12:12 PM
#11
Staging Lane
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Update, I went out during my planning period and unplugged the MAF and the truck idled great. I don't think it is the throttle body and I don't think I have a vacumn leak. Tonight I am going to change the placement of the MAF to see if that fixes my problem.
12-09-2013, 01:43 PM
#12
Putting the maf sensor in a different size tube WILL throw your tune off. Something about the maf being resistance based, and the tube diameter changes the resolution of the sensor. I cant tell you the exact reason why. The maf sensor needs to be calibrated for a different diameter tube.
I ran open loop for a while when I was cam only. Had the tune dialed in, and swapped from my stock air intake to a cold air intake with a different sized tube. The truck idled at around a 17.0 AFR after the swap.
IMO it sounds like the maf needs to be calibrated. What afr is it idling at with the maf plugged in?
I ran open loop for a while when I was cam only. Had the tune dialed in, and swapped from my stock air intake to a cold air intake with a different sized tube. The truck idled at around a 17.0 AFR after the swap.
IMO it sounds like the maf needs to be calibrated. What afr is it idling at with the maf plugged in?
12-09-2013, 02:18 PM
#13
The MAF has been retuned for it. However, the MAF hz changes by over 1000 hz at idle from 1700 to 3200. Leads me to think that placement is the fix for it. Fuel trims are +/- 2 when the hz hold steady. I've tuned 5 different Procharger setups and this is the first one that has surged with me which leads me to believe its the MAF placement but if its something in the tune with the new MAF sensor that needs to change, I'm all ears.
12-09-2013, 07:50 PM
#14
Staging Lane
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Moved the MAF to the side away from the bottom and no improvement. Still surging like normal. I unplugged the MAF and everything settled down and the engine quit surging. Plugged it back in while the truck was running and it idled fine. Turned it off and cranked it back up and it started surging again. It has to be something in the tune.
12-10-2013, 01:07 PM
#17
How much boost are you planning on running? You will be OK with the MAF under 10lbs, but I would recommend you change your MAP sensor out and runs SD tune. Much better for boosted applications. That way, the only thing your MAF is used for is the IAT sensor.
12-10-2013, 01:35 PM
#18
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Mine surges from time to time also, lean rich lean rich. Some one told me to check the following fuel trims at one time or something of that nature, but i never have, do to not being super eFI live savy. Curious to see what you find out. My MAF is right at the 90 deg turn by the old intake box bracket.
12-10-2013, 06:28 PM
#19
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Went through about 8 different tunes today trying to dial it in. Still a little better but not much. When driving it today, I took it up to about 4k to 4.5k on the tach. At those rpms, the trans doesn't know if it wants to downshift, hold steady, or what. One time, it even went into neutral or atleast it felt like it did. Who knows?
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