Need to know more 'bout the Decel valve

Bruce Allert · 03:38 PM

Since puting all settings to factory for the 1.7 EB (Calif.) I am having trouble with high idle (1600-2000 rpms). Dwell set at 47, timing at 27BTDC, idle at 900 rpms. The AAR works and shuts tight! I can crimp the large hose coming from the middle of the decel valve and the idle drops to normal. All the hoses are new, all the hoses have clampes. Where can I get more info on the decel and can it be overhauled? Also, looking at the FI diagram I noticed the small vacuum hose coming from the small end of the decel attaches to a different position than mine. It goes to the hose coming from the lower port of the AAR. The larger hose coming from the middle of the decel goes to the upper port of the AAR via a "Y" which also attaches to the rubber air intake boot that the air cleaner attaches to. Could this be the culprit? Hope this explanation can be followed!

Any thoughts?
bruce

pbanders · pbanders's Garage

Remove your decel valve and try blowing through it. If you can, it's defective. AFAIK, there is no way to fix it, you've got to find another one.

Unless you're trying to pass smog, I'd suggest you simply remove the decel valve and cap the ports on the plennum and air box. It is only a secondary emissions control device, and is not essential for the car to run properly.

Bruce Allert · 11-13-2002, 08:32 PM

Thanks Brad, I'm gonna do that right now... just so I can quit try'n to figure out what AFAIK stands for!!!

If I lay awake tonight think'n 'bout them letters it's all yer fault!

Hey, thanks again man......
bruce

JWest · 11-14-2002, 04:49 AM

In case you didn't get it "As Far As I Know."

Bruce Allert · 11-14-2002, 05:16 AM

AHHHHHhhhhhhh, that's better! Sometimes that "letter speak" gets the better of me!.

Now I can go on to other things... thanks James, I feel better now.

I took the decel off last night, tried to blow thru it but it was closed so I guess it was working. It just bugs me to know there is a differeint reason for its not decelerating. After taking the decel off I had to open the idle screw to get it up to 900 RPMS. Before I did that it would hunt from 900 down to almost stall. I'll take it out today and get it nice & warm. That should tell me if I have to tinker more.
bruce

3D914 · 3D914's Garage

Bruce,

Did you get the problem with the Decel valve figured out?

From your description it sounds like its hosed up wrong. It doesn't make too much sense to have the AAR routed together with the decel valve.

I'm assuming here that the Djet config is basically the same for the 1.7 & 2.0.

The small end of the decel valve should go to a T that connects to the plenum (air) box beneath the Throttle Body. The upper hose of the decel also goes to the plenum box but above the throttle body. The larger horizontal hose also goes to the plenum box below the TB.

The AAR hoses have one coming from the air box (above the TB), and the other going to the air box (below the TB) near the cold start valve.

Hope you get things worked out.

Regards,

Bruce Allert · 11-14-2002, 07:26 PM

Thanks Gerard. I looked at an EA 1.7 (mines an EB Calif.) and it is as you described. Mine has a few more hoses prolly due to its needing more smog stuff. The small hose of the decel went into a factory fabricated "Y" just after the AAR and before the plenum. The larger center hose from the decel went into another "Y" before the AAR upper port and those hoses connected into the air filter boot. It all ran fairly well (but not much power) before I changed out the 2.0 injectors to 1.7's, did new points, cap, rotor, plugs, dwell & timing. Now I have about 40% more poop. I tooks Brads advice last night and took out the decel. It runs really good but still can only get the RPMs down to 1000. I'll replace the injector seals and the oil filler breather housing gasket along with checking all the NEW vacuum hoses again for leaks.
I'll get it one of these days. It sure is fun to drive with all this new found power! WHAT A CAR!

bruce

3D914 · 3D914's Garage

Bruce,

While you're checking things. I've been chasing down vacuum leaks since I bought this car over a year ago. Of course changing engines didn't help the equation. But I've come across a couple of spots you don't often hear about that caused me some grief.

1) Injector seals. You'll hear about this one, and since you're replacing these, make sure you use new seals.

2) Oil filler gasket. Don't rely on the bail wire to secure this thing. Use some gasket sealer on both sides of the gasket. Also check the oring under the filler tube as well.

3) Rubber seal atop the throttle body. Mine was dried out and was not sealing properly.

Good luck with the idle.

Bruce Allert · 11-16-2002, 06:18 AM

Gerard, Thanks for the extra areas to check. I'm going to the FLAPS this morning to pick up that stuff you mentioned plus a new Haynes manual that's not greasy to keep in the house (on the back of the throne!

). I discovered the gasket on the oil fill by accident. The port to which the hose connects was loose so I flipped the bail, took off the top and there was the gasket in 3 pieces. Had an old hard one that I greased up to get it softer but I think it didn't form well.
This'll be fun... I have a "grocery list" now! More reason to wander the isles of the store.....

bruce