Bird still flying low!

fixmysc

Registered User
Hi folks;
I'm starting a new thread about my '95 bird with the rebuilt engine that won't idle well at all. Thanks for all your previous input. A couple of updates, and some more question as I try to get this bird to fly "straight".
I've now replaced both O2 sensors, reconnected and checked all plugs and wires (plugs are very black), tried to put propane over most of the vacum lines with no effect, checked (visually) the crank sensor, and put some injector cleaner in the tank. So far everything seems in order, but it still idles very, very rough with lots of popping.
However, CEL light is not coming on, but after driving it around the neighborhood for 20+ minutes (no plates or hood!) this evening, I pulled into my shop to check the transmission fluid with it running in neutral. The passenger side catalytic converter was very bright orange, glowing, even with my shop lights on! I immediately checked the drivers side cat and it was normal, no color change. What does this mean, I mean, it was almost liquid hot!
Next, I would like to check for vacum leaks, so I bought a regulator for my air compressor, but I'm not sure how to do this without air just going into a cylinder and out an exhaust valve. I've search here, but can't seem to locate directions on how to pressurize as to check for leaks.
Thanks, still enjoying the journey, and all the help!
Art
 
what do you mean by popping - where

what temp does the motor run

the cats get hot but i dont think they should glow or be almost liquid hot
maybe there clogged

black plugs -running rich ,fouling ,oil -what gap are they -how old are they
what wires and there age

whats the vacum gauge read at idle

cheers
 
I think glowing cats is a sure sign of running very rich. Do you have an extra set of injectors that you can throw in, as you may have one stuck full open on the pax side.
 
i dont even think clogged cats would make them glow red hot.

check your spark plug wire order............and then check it again
 
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Problems at idle

what do you mean by popping - where

what temp does the motor run

the cats get hot but i dont think they should glow or be almost liquid hot
maybe there clogged

black plugs -running rich ,fouling ,oil -what gap are they -how old are they
what wires and there age

whats the vacum gauge read at idle

cheers

Thanks for the response. I've been through most of these concerns on the previous ('bird flies again sort of') post. But to recap, when the motor is popping, it sounds like a typical backfire, which seems to be in the S/C tubes. Tubes are tight and were sealed with permatex gasket maker before assembly. However, I've ordered some teflon gaskets to be certain.
After 20 minutes of driving around the neigborhood, the temperature gets to about 1/4, I've not run it longer than this yet.
As far as the plugs are concerned, I'm using new, autolite xp 5144, gapped at .53, new autolite wires, and have checked the order several times using diagrams posted here to ensure I have it right.
The vacum gauge stays pretty much at zero, except when I rev it up when it will deflect to about 10. While driving, the acceleraltion is very sluggish, but will eventually kick in showing a small amount of boost on the gauge. Keep in mind, by the time it does kick in, I'm at the end of the block. As I mentioned previously, I have very little brakes and have to stand on them with both feet to stop, no lights are coming up on the dash while driving.

How does one do a proper test for vacum leaks? I have an air compressor and regulator, but how do you keep air from just rushing out the exhaust valves?
Also, can I use a tire gauge to check the pressure on the fuel rail? Would that reveal much about the injectors?
Thanks for the help,
Art
 
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if the popping is out the exhaust id say check the firing order of the wires one of them is wrong (mix-up) -most likely on the drivers side -that happen to me after doing the head gaskets

the gauge for vacum/boost -at idle should read 20-22psi vacum
for fun -regap the plugs to 035 - 045 -i use 045 and seems to work well
wire tie off the vacum hose so there on tight

as for the no brakes -hard pedal -id say be extremely careful ,sometimes keeping the master cyl full of fuild might help
,but you know something will have to be done about that soon -i have that problem ...a leak ...and when the fuild level is to low -here come the hard pedal (stand on the brake's) ,not a good feeling ,if you know what i mean -this is my next project on the car -my brakes ,as long as there is enough fuild they seem to work ,i check this before driving it away -keep fuild with you ,but none the less this is bad

cheers

cheers
 
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i know this is rough but should work
 

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Spark plug order

i know this is rough but should work

Thanks for the diagram, but I'm certain its incorrect. I'll show you the one I have been using. Just to be certain, I changed the plug order to the one you indicated and it really ran bad. It would appear that your diagram has the drivers side cylinders 5 and 6 backward. So I'm even more certain now that my plugs are in the correct order

This page won't allow me to reload the image for my current configuration because its already on the post: "the bird flies again sort of"

How do I do a leak test for the air system, ie., S/C and vacum lines ?
Can I check the fuel pressure rail with a tire pressure gauge?
 
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i went out and looked but at any rate this is the one i meant to put up....sorry

cheers

question ,the popping -is it at the exhaust -like its mis-firing ?
 
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The vacuum gauge stays pretty much at zero, except when I rev it up when it will deflect to about 10.

Something is really not right there! The gauge should read somewhere around 18-20 in/hg at idle. When you say 10, do you mean +10 PSI boost?

For the record: vacuum (left side of the gauge) is measured in in/hg (inches of mercury) and boost (right side of the gauge) in PSI.

Was just the cat glowing or the exhaust manifolds as well? If the entire manifolds were glowing, it's likely running lean. If just the cat was glowing, then it's likely running rich.

Sorry if this info was in your other thread, but can you give us some details: Is this a fresh rebuild? Did it ever run well? Who put the engine together? Does it have a good balancer?

BTW: Fix the vacuum issue and I bet your brakes will start working a ton better :)

Vince
 
i went out and looked but at any rate this is the one i meant to put up....sorry

cheers

question ,the popping -is it at the exhaust -like its mis-firing ?

Thanks for clearing that up because the diagram you've just posted now is exactly the same diagram that I'm using, and yes my wires and plugs are exactlly as shown. The popping apears to be in the S/C tubes and not the exhaust, sounds like backfiring or "popcorn" going off in the tubes.

At idle I mean to say, 10 in/hg of vacum only when reved up otherwise its pretty much at zero. I understand this is atypical, but how do I do a pressure test of the system without loosing air down the exhaust valves?

It is only the cat on the passenger's side that was glowing, not the manifold. I know its running rich because when I check the plugs, they are black and sooty.
Thanks, Art
 
You know, its really beginning to look like a or some intake valve(s) are not closing completely and your getting backfiring into the intake.

Who did the heads etc and did they set everything up right for the valves?
 
The rest of the story

Something is really not right there!
Sorry if this info was in your other thread, but can you give us some details: Is this a fresh rebuild? Did it ever run well? Who put the engine together? Does it have a good balancer?

BTW: Fix the vacuum issue and I bet your brakes will start working a ton better :)

Vince

I bought the 95 sc from an elderly gentleman who took very good care of his car and managed 200, 000Km on regular gas, didn't know otherwise! He spun a bearing and the crank was toast. Everything else on the car except the cruise was in good working order. Next I bought a '94 longlock with heads from a member here with only 12,000 km on a rebuild before the car was written off (bent unibody). I stripped the motor pretty much completely except for the heads to make sure it was indeed relatively fresh. Everything looked good and I cleaned and repainted all parts as I reassembled. The seller assured me the engine was running well in the written-off 94 before selling to me.
So I've rechecked the balancer, crank sensor, plugs and wires, all the obvious stuff, but still it runs rough at idle. I never touched the cam position sensor during my clean-up
How do I check for vacum leaks without loosing air through the valves?
I sure hope this is also related to the brake condition also.

P.S. I included several pics on the other post.
Hope this helps, thanks
Art
 
At idle I mean to say, 10 in/hg of vacum only when reved up otherwise its pretty much at zero. I understand this is atypical, but how do I do a pressure test of the system without loosing air down the exhaust valves?

That's is not typical! As I (and others) have said, it should be somewhere around 18-20 in/hg AT IDLE. When reved, it will go towards zero (middle) and then into boost. Once you let off the accelerator, it should "snap" back to around 20 in/hg.

I've never done a pressure test so I can't comment ;) I think you count on loosing some air out the exhaust valves; you just keep the compressor hooked up while looking for leaks. You don't need a lot of pressure; I seem to remember reading about 5 PSI? That should be enough to spray some soap water and see it bubble.

How did you time (crankshaft to camshaft) the engine when you put it back together? I'm starting to think like fturner.

Can you take a video of it running and post it?

Vince
 
vacum guage readings

That's is not typical! As I (and others) have said, it should be somewhere around 18-20 in/hg AT IDLE. When reved, it will go towards zero (middle) and then into boost. Once you let off the accelerator, it should "snap" back to around 20 in/hg.

I've never done a pressure test so I can't comment ;) I think you count on loosing some air out the exhaust valves; you just keep the compressor hooked up while looking for leaks. You don't need a lot of pressure; I seem to remember reading about 5 PSI? That should be enough to spray some soap water and see it bubble.

How did you time (crankshaft to camshaft) the engine when you put it back together? I'm starting to think like fturner.

Can you take a video of it running and post it?

Vince

Hi Vince,
I know that the vacum situation is not typical, I said its atypical.
As far as the crankshaft and camshaft are concernend, I never messed with them, I merely pulled all the components of the engine, including the oil pan, sump, and windrige? (top/bottom), to inspect. But in never removed the heads, or anything related to timing (crank/cam sensors, etc.)
I am looking for a digital camera now that will allow me to shoot some video so you can have a look at how it runs.
 
also for you psi test with your air compressor if an exhaust and a intake valve are open at the same time you have a prob....

so ther is nothing to worry about with that just hook it up and do your test.. you shouldnt have any probs with leaking unless you have a vac leak..

and to me sounds like you have a very bad vac leak because like every one else said you should get 18-20in/hg and if your not seeing much boost also then that would lead to more of a vac leak(and then like someone else said thats why your brakes are hard to push...


so with this reasons i think its a vac leak
 
I know that the vacum situation is not typical, I said its atypical.

Sorry! I missed the "a" :rolleyes:

Take a look at your bypass valve. See this post:

http://www.sccoa.com/forums/showpost.php?p=646787&postcount=3

How did you check the harmonic balancer? I believe some people have had them fail, yet still look OK (not wobble). The issue is that the balancer separates from the sleeve, allowing it to spin on the crankshaft. This causes the timing to be out even though the balancer still visually looks OK.

A video would be great!

Vince
 
if im understanding you right your saying with the bypass closed that he is making boost witch is then making the gauge show 0in/hg because his blower isnt going fast enought to show +boost on the gauge..

if this is what you mean

when my bypass is unhooked it dont make the car run like crap nor does my in/hg change on my gauge so that is false.. unless my car has an issue..:confused: :eek:


Sorry! I missed the "a" :rolleyes:

Take a look at your bypass valve. See this post:

http://www.sccoa.com/forums/showpost.php?p=646787&postcount=3

How did you check the harmonic balancer? I believe some people have had them fail, yet still look OK (not wobble). The issue is that the balancer separates from the sleeve, allowing it to spin on the crankshaft. This causes the timing to be out even though the balancer still visually looks OK.

A video would be great!

Vince
 
My two cents:

Low vacuum pressure at idle is not always because of a vacuum leak! Im sorry to say this but 20" of hg is not a universal constant for our motors. For example; Mismatch wires #5 & #6 and you have instant 7-10" of lost vacuum, "smooth" idle and no acceleration.

Black plugs are not always caused by running rich either, they can be caused by a weak or mis-timed ignition. Dont believe me, do a google :).
 
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