$50 To help solve this problem
#1
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$50 To help solve this problem
1999 trans am
390, turbo , 4L80e
Here's the issue I accelerate and at right around 5500 rpm the pcm does a reset with the swing of the gauges and the trip meter reset, also my wideband looses power and resets.
I attached a short datalog, frame 195 is where it does the reset, if you look at the afrs you can see how they drop down to 10 that's the wideband powering back up.
I'm thinking it's somewhere in the electrical, I datlogged the voltage and it does it everytime.
If someone knows what's causing this I will gladly paypal you $50. Worth every penny to get this resolve.
thank You
390, turbo , 4L80e
Here's the issue I accelerate and at right around 5500 rpm the pcm does a reset with the swing of the gauges and the trip meter reset, also my wideband looses power and resets.
I attached a short datalog, frame 195 is where it does the reset, if you look at the afrs you can see how they drop down to 10 that's the wideband powering back up.
I'm thinking it's somewhere in the electrical, I datlogged the voltage and it does it everytime.
If someone knows what's causing this I will gladly paypal you $50. Worth every penny to get this resolve.
thank You
#3
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Check all of you grounds on the block and heads before you go any further. Tug on them lightly to verify they are strong I have seen these cars many times break a ground wire inside the insulation where it is not visible but will stretch like spaghetti when you lightly tug on it. Then grab the harness with the engine running in the area where it crosses over the top of the air box to the passenger side valve cover wrench and stretch and pull in the drip loop area I have also seen them break various sensor and power wires in the insulation in the same manner as above in this area. Last but not least double check your pcm connectors to make sure they are clean and snug. Look for wires burned against headers and or hot side turbo piping. Check the battery cables to make sure they are tight and all of the block to body body to frame grounds.
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Lets play shots in the dark on the internet. lol - your log file scares me for a turbo car anyway but
ok, if it happens every time at 5500 and your voltage is dipping out - and you've changed the alternator...
what I see is a voltage drop @ about 4400 - you have too many things running on the scanner to spot when it actually drops. So things to check-
The grommet on the back of the alternator that covers the + positive terminal from possibly grounding out as the engine starts to Rev up @ 4400 u can see it makes 13.3V right before it startrs to dip. So next I would check things that are requiring an increased draw at this point. Recheck the voltage at the coils, their connections and grounds AGAIN. Check the fuel pumps wiring, I would be inclined to assume that the pump has insufficient power or grounding.
It really has to be a bad wire somewhere- loose connection on the pump or something silly like that. Not knowing everything about the car makes this kinda thing hard.
Does the car have AC? maybe the alternator belt is slipping once you pass the stock AC clutch disengaging value of 4,294, . Are there signs of belt wear or slippage showing? Possibly check the tension and idler pulley, maybe the whole system is getting too tight under that kind of load.
P.S.
Wtf is with your fuel trims being 6% different side to side. I hope your wide band is on the driver side of the motor, or this issue wont be your last.
ok, if it happens every time at 5500 and your voltage is dipping out - and you've changed the alternator...
what I see is a voltage drop @ about 4400 - you have too many things running on the scanner to spot when it actually drops. So things to check-
The grommet on the back of the alternator that covers the + positive terminal from possibly grounding out as the engine starts to Rev up @ 4400 u can see it makes 13.3V right before it startrs to dip. So next I would check things that are requiring an increased draw at this point. Recheck the voltage at the coils, their connections and grounds AGAIN. Check the fuel pumps wiring, I would be inclined to assume that the pump has insufficient power or grounding.
It really has to be a bad wire somewhere- loose connection on the pump or something silly like that. Not knowing everything about the car makes this kinda thing hard.
Does the car have AC? maybe the alternator belt is slipping once you pass the stock AC clutch disengaging value of 4,294, . Are there signs of belt wear or slippage showing? Possibly check the tension and idler pulley, maybe the whole system is getting too tight under that kind of load.
P.S.
Wtf is with your fuel trims being 6% different side to side. I hope your wide band is on the driver side of the motor, or this issue wont be your last.
#11
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Buffjoey the fuel trims is something new with pcm resets.
I'll check the fuel pump wiring and grounds, no A/C thanks for the input. I've been running Trick 114 in the car.
I'll check the fuel pump wiring and grounds, no A/C thanks for the input. I've been running Trick 114 in the car.
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Check the battery cable connection at the power distribution center on the drivers side wheel well. I've seen that terminal get loose and or burn out of the PDC. You can run a 8 gauge jumper from the battery to the PDC as a process of elimination.
Drop the panel under the column and make sure someone in the past did not put in a alarm that interupts the pink ign wire coming out of the ign switch.
Drop the panel under the column and make sure someone in the past did not put in a alarm that interupts the pink ign wire coming out of the ign switch.
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Check the battery cable connection at the power distribution center on the drivers side wheel well. I've seen that terminal get loose and or burn out of the PDC. You can run a 8 gauge jumper from the battery to the PDC as a process of elimination.
Drop the panel under the column and make sure someone in the past did not put in a alarm that interupts the pink ign wire coming out of the ign switch.
Drop the panel under the column and make sure someone in the past did not put in a alarm that interupts the pink ign wire coming out of the ign switch.
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You could always get real ghetto and run a set of jumper cables from the battery to the alternator and from the batter ground to the engine block. If that doesn't change anything run the jumper cable to the alternator / battery , and the other to battery+ and power + distribution on the passenger side.
#16
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You could always get real ghetto and run a set of jumper cables from the battery to the alternator and from the batter ground to the engine block. If that doesn't change anything run the jumper cable to the alternator / battery , and the other to battery+ and power + distribution on the passenger side.