Hey folks;

Almost got the old L98 running nice. Just rebuilt and cleaned up the throttle body, reinstalled, replaced a few hoses and, wow what a difference. No more crazy idle and hesitation, well almost.

2 problems

1. I went to replace the PCV valve and hose. The hose was chewed up where it connects to the tube that ultimately connects to the intake. I went to put the new hose on and the fitting on the tube broke off. Crap! I removed the tube and it looks like it was already broke. previous owner tried to fix with what looks like RTV. There were globs of it all over.

So, question one, is this tube something I have to replace, or is there a better solution. All it is is a flare fitting on the end that goes to the intake on one end, at the other is another barb fitting that a hose connects to ( I think off to the EVAP system) and in the middle is a barb fitting for the PCV. Simple enough, but couldn't find one at the usual corvette supply places..

problem 2. So I stuck my finger over the leak to listen to the smooth running engine and heard a hissing sound. another leak? jeeze, no wonder this thing ran so crappy. Long story short, there's a rubber hose fitting that connects to the EGR solenoid. One side goes to the throttle body while the other goes to the EGR valve. It looks like the rubber thing converts the hose size for the solenoid to a smaller diameter for the TB and EGR valve. Well, this little rubber thingie was split on one on one side. So, all it was ding was sucking air. I'm guessing this was causeing the EGR not to function properly and contributed to my roaming idel.

Question - where can I get one of these things, or can I get diffent hoses so they fit on both ends? Couldn't find it in the usual Corvette places.

I'm going to take a ride to Autozone at lunch to see if they can help, but I'm usually not successful with those guys unless it's on the shelf.

Thanks folks for any help. After this, I'm hoping Im done chasing these bugs.

Bob

 

if you had a few plumbers tools you could make that using the old flare fitting, if you cant get it any where else take it to a plumbing shop ,with a box of donuts of course, they'll probably do it for free

 

You may want to examine very carefully the vacuum diagram (if it is still there) sticker on the radiator to ensure vacuum lines are routed correctly and the appropriate components are there that they operate/rely on. The prior owner may have done some additional DIY stuff that is not exactly right based on your description of what you have.

For example, the tube from the EGR valve should be connected to the EGR control solenoid and the solenoid should have a line going to the manifold port on the bottom of the throttle body with a tee fitting in there that goes up to the EVAP stuff I believe.

Use the correct vac diagram for your car to verify before hooking up the lines to ensure proper operation.

 

Though I haven't had to look for awhile, that elbow was available at most Discounters along with assorted vacuum connectors and vacuum line.

 

If you can't find that little 3 way rubber plug you're talking about, you can fix it with silicon. Force the crack open and totally clean it with alcohol then use black silicone to fill the crack and a little on top. The original purpose of the stuff is for rubber, RTV stands for 'room temperature vulcanizing', it's made to fuse rubber without heat.

Greg

 

Not on 85/86





Later TPI had that T you mention

 

Yeah, I'm considering just recreating the thing with some plumbing tubing. I'm checking on line first to see if I can pick one up via salvage. When I get a minute, I'll also check the usual auto places on line, though at a quick glance, I didn't find anything. Just have to hang the wife's cieiling fan before I try to reconstruct the vacuum tuve or I'll never hear the end.

I did find some fittings that would replace the little rubber thing that plugs into the egr solenoid. If they don't do the trick, I'll definately fix it. I didn't think of the RTV solution.

Oh, and I did verify all the vaccume lines. It looks like al my lines are correct, just some of them aren't completely leak free. I also found a dry rotted line at the cruise control cervo. replaced that as well. I think once I have these last couple of lines fixed, at least my vacuum leaks should be solved. Then I can time it, set the idle and (fingers crossed) I should be in business.

Thanks again for the responses.

 

I may have that aluminum tube for PCV/Purge, as I couldn't use it with my Super Ram. I may also have the EGR part.
I'll have a look after work.

 

Found the tube, no luck with any EGR parts.