CA18DET and idle issues!

[boost_boy]

It's starting to be a constant topic with idling and driveabilty problems. Here's a winner: There's a seal between the butterfly valves that will go bad over time (been there and done that) and it sounds like the injectors are sucking air. Once this goes bad, you car will idle like garbage and you will have driveability issues out the yang-yang, but I know most wouldn't even think of that one. Check it out and make sure that this is not your issue.

Dee

[xyster]

you mean the gasket between the chamber part and runner part of the intake manifold? I'm sure those aren't the actual names...but I imagine you know what I mean. If so, I replaced that when I put the motor in.

[minutericesentra]

I think he's talking about the shaft seals, where it penetrates the runner's wall.

[boost_boy]

Quote »I think he's talking about the shaft seals, where it penetrates the runner's wall.[/quote] That's the one! Wanna do a test? Let it run and pour water in there tosee if it gets sucked-up. Thanks for clearing that up, Jon.

Dee

[minutericesentra]

Hey Dee, sorry to get off topic but I didn't think this needed it's own thread, you wouldn't happen to know if the valves in the CA16 and CA18 heads are the same would you? Reason I ask is I was checking out my DET the other day and my trashed CA18DE head was sitting there so I measured the valves out of curiousity, I find that my old *** DET has smaller intake valves then the pulsar's DE head! I was kinda pissed already since I didn't find a crank girdle hiding under the oil pan like I was expecting, I've never heard of or seen a DET without one, maybe I'll just make one when my welding skills get a little better. The cams appear to be a lower profile in the DET as well but haven't had time to measure but it's not a big deal anyways since I'm not keeping them. So, any thing else you(or anyone else) can think of that I need to look out for like valve reliefs if these pistons check out ok? that's the only other thing I can think of for now.

[boost_boy]

CA16 and CA18 valves are the same. You can actually get a crank girdle from one of the guys who have a bad DET or from a N/A RWD CA, but you will need the crank bolts as well. The DET does have valve reliefs on the piston skirts. I already knew the head was a bit different, but I'm surprised the bottom end didn't have crank girdle. And lastly, I really do think this subject needed it's own thread because not only is it a problem known to happen with CA DOHC motors, it was never discussed here before which deems this topic a candidate for an individual thread.

Dee

[minutericesentra]

Okay, I guess I'll start a thread then to let more people know about this, I gues I'll continue my questions there as well.

[boost_boy]

Quote »Okay, I guess I'll start a thread then to let more people know about this, I gues I'll continue my questions there as well.[/quote] That's one of the privileges you have especially when you're covering a topic that has never been discussed before. So go for it!

Dee