Big T
Well-Known Member
OK, finally finished installing the new exhaust. Also got the crossover pipe back in with the temp probe on the driver's side just below the manifold. Gotta say, this was a major PITA to get back in. It was one piece and near impossible to line the bolts back in correctly. Twice I've installed one piece crossovers and I've never had problems like this. This was further complicated by the fact that the truck was parked in the backyard and we're experiencing torrential rains. Yep, I laid out vinyl coated drift chutes from my boat and donned the foul weather gear to roll around in the mud to get this done. Had to as I don't have the option to do it during the week due to travel. I ultimately had to drop M8 bolts through from the back side of the exhaust manifold and use nuts and washers to complete the installation. Several trips to Home Depot to get the right bolts.
I also had Bill Heath revise my GL 4 programming for the ATT in the hopes that my DTC 1656 code would disappear.
Recall that the downpipe sheared off at the junction to the original exhaust section:
Also recall that the original exhaust section came replete with the factory clearance restricitions:
The rest of the exhaust was also shot:
So I broke down and bought the Diamond Eye 4" kit from the downpipe back. Downpipe was sort of a bitch to get in place and connecting the rest of the exhaust was not the most intuitive and could have used better, more specific instructions. As mine is a '99, I have a year to cut in a soot trap to pass smog. I have two, one from the '95 and the gutted one from the '99 (nice that it was gutted, but to minimal effect given the prior clearance restriction). I'll have to modify one so that it's 4" in and out.
Some here said that the new exhaust should result in noticeable changes. Well it definitely did. Go back to my initial reaction posts to this '99 and I said it was noticeably louder from the engine compartment than my (now my son's) '95. That is virtually gone and it's all coming out the pipe, including the turbo whistle. I'm thinking that noise was back pressure from the clearance restriction in the stock section of pipe.
After doing the security clearance cycles (twice, and did not clear the light), I did the one minute koko thing with the accelerator pedal so the ECM could relearn the timing. Time to take it for a spin.
Wow, this truck is now a real beast. It's raining like hell here, so streets are slick. However, if I step on it, particularly in a turn, when the turbo really kicks in it gets loose and very squirrely. Also noted that it's running a tick cooler on the gauge, not that it ever ran hot to begin with. Very impressed.
Now the bummer is I'm still getting the DTC 1656 code and the security light keeps popping up. I'll deal with those later. At least now I have my truck back, as I need it for some fishing over the holidays.
I also had Bill Heath revise my GL 4 programming for the ATT in the hopes that my DTC 1656 code would disappear.
Recall that the downpipe sheared off at the junction to the original exhaust section:
Also recall that the original exhaust section came replete with the factory clearance restricitions:
The rest of the exhaust was also shot:
So I broke down and bought the Diamond Eye 4" kit from the downpipe back. Downpipe was sort of a bitch to get in place and connecting the rest of the exhaust was not the most intuitive and could have used better, more specific instructions. As mine is a '99, I have a year to cut in a soot trap to pass smog. I have two, one from the '95 and the gutted one from the '99 (nice that it was gutted, but to minimal effect given the prior clearance restriction). I'll have to modify one so that it's 4" in and out.
Some here said that the new exhaust should result in noticeable changes. Well it definitely did. Go back to my initial reaction posts to this '99 and I said it was noticeably louder from the engine compartment than my (now my son's) '95. That is virtually gone and it's all coming out the pipe, including the turbo whistle. I'm thinking that noise was back pressure from the clearance restriction in the stock section of pipe.
After doing the security clearance cycles (twice, and did not clear the light), I did the one minute koko thing with the accelerator pedal so the ECM could relearn the timing. Time to take it for a spin.
Wow, this truck is now a real beast. It's raining like hell here, so streets are slick. However, if I step on it, particularly in a turn, when the turbo really kicks in it gets loose and very squirrely. Also noted that it's running a tick cooler on the gauge, not that it ever ran hot to begin with. Very impressed.
Now the bummer is I'm still getting the DTC 1656 code and the security light keeps popping up. I'll deal with those later. At least now I have my truck back, as I need it for some fishing over the holidays.
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