Idle air controller stuck?
Idle air controller stuck?
How can I check this? If that is the case, would it not also cause a problem with the MAF connected?Originally Posted by crzy8mnky
Thx!
I would grab the IAC of your old throttle body and swap it out. Might also be a tune issue, maybe someone fat fingered the idle settings. As for the MAF, if the tune is not calibrated for the difference MAF then it will not run right because there is a difference in the amount of air that is actually coming in vs what the computer thinks is coming in. I ran into this issue when I reused my MAF from my 5.7, it was calibrated differently than the 5.3 MAF and caused run issues. If the calibration is was off then it definitely could cause it to not run.
Hmmm. I decided to pull the intake elbow off and plug the idle air port off, and it fired right up, and stayed at a high but reasonable 1400 rpm. Didn't feel like a lot of suction on my finger, so I remove and nothing changes to the idle. I go ahead and played with the TB (which looked fully closed) and was able to push it in slightly more closed and the idle dropped a bit (say 1100 rpm). I decided to let it run that way for a bit to get it to operating temp and make sure fans are working. But then I decide to put the elbow back on while running and connect the MAF. I do that, and no immediate change, and then periodically it would stumble really bad (like trying to make the maf work) and then it would go back to its 1400 rpm. Kept it going for several minutes; temp got up to 212 and then efans kicked on and temp dropped back down. Put it in gear (but did not move it) and the trans loaded, put it back in park and then turned off. Went out a few minutes later (w/MAF still hooked up) and it started the same as before, w/intermittent stumbles but it didn't die. I think it may be able to go over to the lift now and start building an exhaust!
I took out the complete harness so Lextec could integrate LS wires, and I can't remember which side is which WRT the O2 sensors. One of them was mounted to a bracket. Anybody know where this bracket mounts; which side is it on?
Thx!O2 sensor.jpg
Looks like passenger side, mounted on the two bell housing bolts on the side.
I just pulled a 2000 4.8 today and it didn't have that. It does appear to be untouched.
Well, after two days I've completed fabbing the exhaust. Probably should have just taken it to the local muffler place, but I'm happy w/the results. All is now quiet on the western front. Now to get it to the tuner and start driving this thing!
Well, a big fiasco over the weekend. My oil cooler lines that I had fabbed up (marrying the LSx oil cooler hard line w/stock tahoe hard lines going into the radiator) were joined w/Parker compression fittings, because I couldn't get anyone to make the factory hard crimp style. One of them started leaking like a sieve. I think the compression piece that fits over the hard line had not dug into the line when tightening. So oil went everywhere. And the line is under the motor mount and the bolt holding it to the block is almost impossible to get to. I spent 5 hrs yesterday getting it off--I won't put it back on since I can't trust that fitting to work; I put a block off plate on for now. But I was able to finally get it into the tuner last nite. I think he'll have it a few days as he is swamped. Can't wait to get it back running right.
Definitely sub'd to this thread! I don't think you mentioned mating your LQ9 with your trans. Do you have the 4L60E and did you have to make any changes? My LQ9 is going into my '98 ECSB Silverado Z71. Also, did you use the same A/C compressor that was on the 5.7 or the one from the 6.0?
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