slight hesitation on highway?
#25
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my truck will hiccup ever so slightly when i turn the ac on, even with no belt on the compressor. it feels like the compressor is kicking on and of, which of course it isnt. i dont know if thats something in the tuning or what. its a constant thing until i turn the ac off.
There is a ignition timing table that retards the advance by 30* to 40* during A/C compresser comand on and off.
#27
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Same issue here, its a 2004 4.8. I just put tr55"s in and it seems to be a little better but my bet is that under a high load (4th gear around 60 mph light thorttle) is that one of my coils is going weak, just bought a set (well actually 7 coils) of coils from a member here, when I put them in on monday or tuesday I' will let you know.
#28
thanks. Everything on my 02 LQ9 is off the 00 4.8. So stuff is getting old. But if that was the case with the coils you'd think it wouldn't run as good stop and go. It runs great all the way up to redline.......1st gear drop from 30 will light up the rears easily
#29
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I have seen this from experience, I'm a Jaguar Tech and the older S-types 4.0 would act the same way--5th gear cruising around 55-60mph they would hesitate. Usually when we get one of these in the shop we already know that they are in need of coils, which cylinder is it? don't know since its not a dead misfire but just a weak spark under a load and it will not flag a code.
They would run awesome throughout the RPM range but once on cruise around 1800 rpms then it would happen.
Just some info-
The coils should be here on monday and I'll update you that night.
They would run awesome throughout the RPM range but once on cruise around 1800 rpms then it would happen.
Just some info-
The coils should be here on monday and I'll update you that night.