4L60E w/ vacuum modulator = Code P0748
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From: Orange Park, FL
4L60E w/ vacuum modulator = Code P0748 Have a 5 OHM resistor in the pan, coming off the C and D connectors that used to read the Pressure Control Solenoid. I'm getting DTC P0748 and its preventing shift adapts and a 2-3 at WOT. Has anyone here gone vacuum modualted and had this problem?
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From: Sacramento, CA
Re: 4L60E w/ vacuum modulator = Code P0748 Mine has the code also. It seems to shift perfect though I have a Yank 4L60E. The code is for a bad solenoid right?
One of my buddies cars had the same problem but his trans blew up before we could check out the problem. We originally thought it was a batch of bad resistors. When did you buy your kit? And from who?
One of my buddies cars had the same problem but his trans blew up before we could check out the problem. We originally thought it was a batch of bad resistors. When did you buy your kit? And from who?
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From: Chi-Town
Re: 4L60E w/ vacuum modulator = Code P0748 hmm...maybe the resister is faulty
i've installed a few of them when i worked at a trans shop and none of them threw a code
the only thing i think would throw a code is if that resister isn't correct
i've installed a few of them when i worked at a trans shop and none of them threw a code
the only thing i think would throw a code is if that resister isn't correct
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From: Wichita, KS - 1400' above sea level ;-)
Re: 4L60E w/ vacuum modulator = Code P0748 Yes. I have double-checked both the resistance
(5 ohm) and connection. If you want to have some fun you might try a DIFFERENT resistor as that one does not seem to be exactly what the LS1 PCM likes to see.
That is a SOFT code, though (does not set check engine light, at least on my car) nor does it cause any shifting malfunction.
(5 ohm) and connection. If you want to have some fun you might try a DIFFERENT resistor as that one does not seem to be exactly what the LS1 PCM likes to see.
That is a SOFT code, though (does not set check engine light, at least on my car) nor does it cause any shifting malfunction.
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From: From the Bowels of Hell!!! You want some of me bitch?!?!?!
Re: 4L60E w/ vacuum modulator = Code P0748 I have a vacuum modulator kit in mine, but I honestly don't think we installed a resistor of any sort in the tranny, or anywhere else. Mine shfts fine and no codes.
Tim
Tim
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From: Orange Park, FL
Re: 4L60E w/ vacuum modulator = Code P0748 Thanks for the replies guys. We took the eng/trans wire harness out of the loop by cutting the wires by the PCM and putting in different resistors. We tried 5 Ohm and 4.5 Ohm but neither worked. Finally ended up putting a Pressure Control Solenoid (VERY tired of dropping the pan and wasting money on fluid) up by the PCM and the code went away. Unfortunately the 2-3 shift at WOT still isnt happening. I really was hoping it was related to the code!! <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> Oh well the troubleshooting continues....
Re: 4L60E w/ vacuum modulator = Code P0748 </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris99WS6PWTMET:
<strong> Unfortunately the 2-3 shift at WOT still isnt happening. I really was hoping it was related to the code!! <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> Oh well the troubleshooting continues....</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Mine never did make the 2-3 shift at WOT after the vacuum kit install and the tranny blew 2 days after, under normal driving conditions. I had the code as well.
<strong> Unfortunately the 2-3 shift at WOT still isnt happening. I really was hoping it was related to the code!! <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> Oh well the troubleshooting continues....</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Mine never did make the 2-3 shift at WOT after the vacuum kit install and the tranny blew 2 days after, under normal driving conditions. I had the code as well.
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From: From the Bowels of Hell!!! You want some of me bitch?!?!?!
Re: 4L60E w/ vacuum modulator = Code P0748 Why are ya'll putting resistors in the pan and/or by the PCM? Mine works perfect without all that crap. My vacuum modulator makes ALL my shifts firm and quick.
Tim
Tim
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Verdad Gallardo Re: 4L60E w/ vacuum modulator = Code P0748 It's an o-ring resistor and yours has it as well or you are running around town with a flashing ses light. Either that or you had the code removed with custom pcm programming. It's part of the kit.
