96 Upper/LIM Gasket Question
 

Hi, I'm planning on replacing the LIM gasket on my 96' 3.8L vin-K Bonneville this weekend. Reading through the post it sound to me that a lot of you have been able to replace the LIM gasket without removing the belt tensioner. Is this right? I was always taught that you lower the manifold straight down on top of the heads. Looking at this belt tensioner with it's elbow I'm going to have to lower the manifold down on an angle to make the elbow connection then set the back of the manifold into place. Doesn't this screw up the silicone in the corners? I was also wondering what Threadlocker is recommended? Red (High Strength) or the Blue (Medium Strength).

Thanks, I appreciate your help

I'm glad you brought this question up. I've been meaning to make a post on it.

I've personally done four LIM gasket jobs now (three on my or my family's cars, one helping a bud). Each time I did just what you say, "angle" in the LIM onto the elbow, then "rotate" it down onto the LIM gaskets. Of these four jobs, two wound up leaking from the elbow where it joins the LIM. I had to go back in and remove the tensioner to re-install the elbow, and that worked alot better.

From now on, I would personally recommend that the tensioner be removed during a LIM gasket job, because I found it alot easier to correctly install the elbow.

I concur..... and you want blue threadlocker.

Thanks for the replies. I did remove the tensioner but now need to get back to the dealer for another O-ring. I see the Manual also tells me to remove the tensioner but the LIM gasket set don't supply the new O-rings!

I had anti-freeze sitting on top of the LIM by all it's bolts but looking inside with it all apart looks pretty clean for 117K miles. I do see the 2 hidden bolt galleys were filled with oil and appears the Upper is coated with oil as well. Is this common? I change oil every 3K and replace the PCV every 6K. Wasn't expecting to see all this oil. I changed the Upper a few tears ago before finding this forum and didn't know about this LIM gasket problem but didn't recall see oil like this.

Puddles of oil in the corners is pretty much normal.

Well.... car back together and looks good except for 1 new thing. Now I keep receiving a "P0113" (Intake Air Temperature Circuit High Input) code. This IAT sensor is located in the hose that's between the air box and throttle body right? Is there any way to test this IAT sensor? I've wiggled the connection to make sure it's open good. Not sure what else to try.

"high input" (resistance) could be an open sensor (thermistor) or the connector, perhaps. Do you have a meter to check its resistance with the sensor unplugged, power off? You will either get some reading in ohms (good), or it won't read at all (open), which will indicate a bad sensor.

If the sensor reading is okay, it may be the wiring back to the PCM.
Check this with the sensor still unplugged, key on and check volts at the connector (across the 2 wires). If wiring is good, you should get about 5 volts.