I just finished replacing all of the oil metering vacuum hoses because one of them broke, and now my car won't idle below 2000rpm when it's warmed up. This is an 87 Turbo II. The car runs perfectly smooth and starts and revs like normal now that the vacuum leak(s) are fixed, but I can't get it to idle down. Any suggestions?

 

Sounds like you still have a vacuum leak. Did you spray around the intake with it running and notice running differences?

 

Yes, and I couldn't find anything. I used my boost leak tester and all I could hear was a hissing coming from the turbo, which I'm assuming is coming from the exhaust port.

 

It's also idling really rich, right around 12:1.

 

A high idle could be caused by a throttle cable that is too tight, a cruise control cable doing the same thing, throttle plates sticking, fast idle cam not set properly, AFM door sticking open, BAC stuck open, dash pot incorrectly set, air bypass valve that continues to bypass air, TPS incorrectly set and a vacuum hose connected to the wrong spot.

W/the engine idling high press 'upwards' on the front throttle linkage and see if the idle drops.

 

It's definitely a vacuum leak. I sprayed brake cleaner under the intercooler, right where the three vacuum nipples are that get capped during the emissions delete, and it idled down until I stopped spraying.

So, what is in that area that can leak vacuum? Is it possible the vacuum caps I bought aren't sealing? I'll pull the intercooler off and see what I can find later.

 

I pulled the intercooler off and checked everything out. All three vacuum caps are tight and in good shape. None of the oil metering vacuum lines were pulled off. I guess I'll have to pull the UIM off again and look for anything else that could be leaking.

 

or..... make a cheap smoke tester. I have a vid. Paint can, 3/8ths nipples and a couple o rings and smoke bombs etc etc. Hook one end to a compressor/tire inflate, the other to the brake booster hose. pressurize to like 5 psi ish and you will find the leak with the TB opening blocked off.

Granted you have a turbo... so procedure may vary slightly.

Edit: welcome to go exploring however, I learned this way at one point as well.

 

I used my boost leak tester and found that it's coming from the oil metering vacuum system. I'll be pulling the UIM back off and re-checking everything.

 

I finally found my leak. One of my oil metering lines broke.



My next question is, is air supposed to come out of the oil side of the oil injector?

And finally, can you still buy replacement OMP lines?

 

I'm going to be running new lines, so no worry there, but I'm concerned that that oil injector might be bad. Is there a way to test it? I don't feel like air should be getting into the oil supply line like it currently is.

 

The oil injector is not really an injector at all. Honestly all it is, is a threaded nipple that screws into the intake and rotor housings. You have the OMP that pushes oil to the oil injector, and as the rotor passes by, the vacuum created by the rotor helps suck the oil into the engine.

Hence why since your line broke, you have a vacuum leak, because your engine is sucking in more air than it should be and messing with the air/fuel ratio

 

That's good to know. I'm still going to remove them all and soak them in carb cleaner just to be safe. I don't want to have to take the UIM off again for anything.

 

not gonna hurt you one bit.

But, out of curiosity, your first post you said you replaced all the OMP lines, the picture you supplied was an old hose, so what happened here? lol

 

I had replaced all of the OMP vacuum lines, not the oil lines. Either I didn't notice the broken oil line when I did it the first time, or I bumped into it during reassembly.

 

Ahh i see. Its one of those thing when your in there, do it all in one shabang, that way headaches later are less likely

 

Did you replace the upper intake gasket when you reinstalled it?

Did you use any gasket sealant (ie hylomar, or the like)?

That omp line is not your problem. When I pulled my n/a engine to swap with a turbo engine I found that I had a line that looked almost identical to yours, brittle, broken, and no longer attached. My car ran, idled, and had no problems.

 

That oil line was definitely the leak. When I supplied 6 psi of pressure to the vacuum hose it blew air out of the oil side. I used a fresh gasket with a slight coating of black RTV on both sides when I reinstalled the UIM.

 

A little update from today:

I rebuilt the OMP and made new lines. The car now idles like it should, maybe a little low, and AFR looks perfect. After a quick drive to fully warm the car up, I'm not getting oil up the lines. One line has oil about half way up, but it just sends air bubbles. My guess is 1) My hose clamps didn't seal properly, or 2) I shouldn't have reused the copper washers on the pump. I guess I could have somehow messed up on rebuilding the OMP, but I followed the instructions step for step.

 

Since its a hydrolic system, i would think you would have to bleed it before complete assembly, but i could be wrong, i removed mine and started premixing

 

I looked at it again today. The clamps are pinching the lines, causing an air leak on all 4 fittings at the OMP. I'm going to assume that all 4 oil injector fittings are leaking as well. I'm going to order more hose and clamps (and another intake gasket) and try again. :/

 

If you've barely ran on a new gasket, you could probably reuse it with RTV and be good