Northstar Engines and System Technical Discussion Discussion, Intake manifold in Cadillac Engine Technical Discussion; I just found out the reason of rough idle - intake manifold gasket has a leak.
I want to change ...
I just found out the reason of rough idle - intake manifold gasket has a leak.
I want to change the gasket my self. I would like to know if there is something else i could do in addition to this. Is there something else i could clean/change/check considering that i have to take the manifold out?
Any tips of how to do it without any complication? What else should i buy besides the gasket?
I drive a Deville 98 108.000 mi
How's the starter? If it's original, you might consider replacing it since it's right there under the intake manifold. If you want tips, do a search here for changing the starter as it's a very similar process to changing the intake manifold gasket. Also check the cable to the starter for corrosion.
get a fuel line fitting disconnect tool. and push down on the line, not up on the fuel rail. that may sound odd but you cannot lift the steel fuel rail. took me a few times to figure that out. i changed my intake gaskets and it made no difference in idle. than i cracked the intake and had to change that. maybe my new intake is warped like the old one? or maybe NS motors just don't idle well.
a first timer probably will take 2hrs. i reused my old intake gaskets when i pulled the heads. they were flat but i like making extra work for myself. i had no miss before the head job but a slight miss after. so i yanked the intake to do the gaskets. i am surprised they seal based on how the intake feels when you first bolt it down. the gaskets just seem funky. give me the old paper gaskets any time. i have read about warped intakes. mine seems flat but the 2nd intake is used so who knows? maybe it is not really flat. i used a straightedge but come on, its a flipping plastic intake.
96 STS. 110k miles. i have owned it for 8yrs. it is in great shape. i don't put many miles on it now. i watch the coolant level carefully and it never goes down but i do not like the exhaust vapor when it is cold. it just seems to make a little bit more than other cars around me.
I just changed the intake gaskets this weekend. Now my car idles how is supposed to. Cold or warm doesn’t make a difference on how it sounds(just the RPM, normally, is different). It took me close to 4h including running to the store to buy a EGR gasket, cleaning the EGR valve, not the TB (I did that before), took a couple of cigarettes break ,,, etc.
It was a pretty straight job. I torque all nuts at 78in/lb (7f/lb ) , I consider that too much, I actually cracked one corner of the manifold - I don’t know if it was a bit damaged before or the screw was oily. I left that one tighten less than the specifications.
Thank you all for all instructions posted - it helped a lot
Everything is smooth right now. I still don’t know what to do with the stupid P0741 code (TCC stuck off). Does it make any difference if I change the transmission fluid?
Thanks, this is a very cool forum and makes owning a Caddy a lot cheaper.
I think I’ve read almost everything was posted for this code. I just want to make sure I’m not missing anything.
I thought maybe there is something stuck in the torque converter and changing the fluid might help somehow.
Thank you for the quick reply.