Engine Running stock plugs in my aluminum heads

[7991LXnSHO]

I do not how you did the smoke test. I figure you tried smoking through an manifold inlet or hose and watched for smoke out of the PCV valve socket.

I’ve never heard of this test, but here is a brainstorm. How about about doing a low pressure leak down test of the crank case? Do not go nuts and blow out the China rails seal or other gasket. But blocking off the PVC socket, and with a sealing oil cap, the crank case ought to hold 7 psi. If it is leaking, that should make a good hiss or breeze in the intake. If your valve covers or main seals are leaking, it might show that, too. But the hiss or breeze or holding pressure is what will be the tell.

 

[rockyracoon]

I don't remember if you posted already but what is your timing set at?
Timing can have an affect on vacuum.

Around 12 deg

 

[rockyracoon]

I do not how you did the smoke test. I figure you tried smoking through an manifold inlet or hose and watched for smoke out of the PCV valve socket.

I’ve never heard of this test, but here is a brainstorm. How about about doing a low pressure leak down test of the crank case? Do not go nuts and blow out the China rails seal or other gasket. But blocking off the PVC socket, and with a sealing oil cap, the crank case ought to hold 7 psi. If it is leaking, that should make a good hiss or breeze in the intake. If your valve covers or main seals are leaking, it might show that, too. But the hiss or breeze or holding pressure is what will be the tell.

Ok that's a thought. Yeah I capped off the pcv and plugged the throttle body ,also plugged the line going to the booster. But the idle seems fine until it reaches operating temp.

 

[rockyracoon]

You said the car is a 95, have you had it tuned?

No no tune as of yet.

 

[7991LXnSHO]

Ok that's a thought. Yeah I capped off the pcv and plugged the throttle body ,also plugged the line going to the booster. But the idle seems fine until it reaches operating temp.

The TB line snd the brake booster line go to the intake, not the crank case. So pressurizing that will not help with a pressure test or smoke test that tests for leaks on the sides of the intake gaskets you cannot see.
I’m leaning to a problem that shows when the computer goes into closed loop, and that would be sensor, electrical or tuning.

The high RPM could be as frustrating as a small tear it crack in the connecting stuff between the MAF and the TB.

Back to the back to the vac leak idea - Is the needle (fairly) steady or does it have a bounce?
Jrichker has a diagram on other posts that while described for a carb is helpful. Here is a link to an article that might also help.

Mastering the Basics--Reading A Vacuum Gauge | MOTOR

www.motor.com

 

[rockyracoon]

No you may have misunderstood me I was saying that I put a plug in the throttle body and I also blocked off the brake booster line. It's been a while since I pulled that vacuum reading so I'll have to recheck it and see if the needle is jumping I think I remember it was jumping slightly. If I remember correctly it was jumping from like 10 to about 13 HG

 

[96pushrod]

No no tune as of yet.

A 94/95 is kind of expected to run like with aftermarket cams until it’s tuned.

 

[rockyracoon]

Yes I understand but since it idles good until it gets to operating temp.im still thinking something else is wrong. As stated once it gets up over 180* or so it starts idling rough.
Im gonna smoke test it once it's warmed up and see if I can see any smoke getting into the crank case. I think when I smoke tested it before the motor was cold.

 

[96pushrod]

Yes I understand but since it idles good until it gets to operating temp.im still thinking something else is wrong. As stated once it gets up over 180* or so it starts idling rough.
Im gonna smoke test it once it's warmed up and see if I can see any smoke getting into the crank case. I think when I smoke tested it before the motor was cold.

Does the car idle high? Does it run lean? This would be happening at all points, not just when it gets to 180*. If you’ve replaced intake gaskets 4 times with no change, I’d be pretty hard pressed to think that was your problem. Assuming the faying surface was a good match.

It’s possible the car runs decent until it goes into closed loop

 

[rockyracoon]

I've got the idle set around 950 . It's into closed loop within 20 seconds so I doubt it's something surrounding that.. It doesn't trigger a lean code but without a wideband I've no way to tell if it's running lean other than looking at the spark plugs. In the carbureted days you could put your hands over the throttle plates and if the car died out you'd know there wasn't any vacuum leaks. My theory is it may be a vac leak as it heats up while something is expanding.

 

[General karthief]

Just bench racing here since I don't have hands on it, are the coolant tubes still connected to the egr plate? Is it possible the gaskets between the egr plate are old and crusty?

 

[96pushrod]

I've got the idle set around 950 . It's into closed loop within 20 seconds so I doubt it's something surrounding that.. It doesn't trigger a lean code but without a wideband I've no way to tell if it's running lean other than looking at the spark plugs. In the carbureted days you could put your hands over the throttle plates and if the car died out you'd know there wasn't any vacuum leaks. My theory is it may be a vac leak as it heats up while something is expanding.

I wasn’t aware cl came on as soon as 20s in for the t4m0.

I can’t say I’ve ever seen a vacuum leak develop when everything is hot. You could hook a reader up after you’ve cleared codes, then ran for a bit and see if an o2 lean condition appears. If you can get it to idle at 950 then a vacuum leak probably isn’t what you’re looking at though.

 

[rockyracoon]

I wasn’t aware cl came on as soon as 20s in for the t4m0.

I can’t say I’ve ever seen a vacuum leak develop when everything is hot. You could hook a reader up after you’ve cleared codes, then ran for a bit and see if an o2 lean condition appears. If you can get it to idle at 950 then a vacuum leak probably isn’t what you’re looking at though.

There are no codes whatsoever.
Actually I just checked and it's idling around 750-800 . So in the absence of codes what else do you think I should check? I've already swapped out the maf with no change and verified correct tps voltage. Timing is 12*. It never stalled idling in my driveway just now but as stated it will stall when turning the wheels when sitting still but since it's a 5 speed that's no biggie but doesn't seem right and it's more likely to happen when the car is warmed up.
Also the cam was stabbed in straight up.

 

[96pushrod]

There are no codes whatsoever.
Actually I just checked and it's idling around 750-800 . So in the absence of codes what else do you think I should check? I've already swapped out the maf with no change and verified correct tps voltage. Timing is 12*. It never stalled idling in my driveway just now but as stated it will stall when turning the wheels when sitting still but since it's a 5 speed that's no biggie but doesn't seem right and it's more likely to happen when the car is warmed up.
Also the cam was stabbed in straight up.

It probably just needs to be tuned. You can’t change a software problem with hardware.

Be glad it idles at all, the t4m0 in my experience is finicky with bigger cams until tunes.

 

[General karthief]

How much overlap does the can have?
It's not a stock cam right?

 

[rockyracoon]

How much overlap does the can have?
It's not a stock cam right?

It only has a couple degrees overlap. It's the TFS stage 1.

 

[vristang]

Have you capped off the pcv, and hooked a vac gauge to the crankcase? Should only get pressure, unless there is a vac leak in head/intake gasket?
Just make sure vents and all are capped off…

I thought CL didn’t trigger until full coolant temp as well, but it has been a while???

Have you looked at the PS pump/sensor?
You mentioned it likes to stall when turning…. Could be the ecu not getting the PS signal, or pump has excessive drag, and iac can’t compensate quick enough?
Might be a reach though?

 

[General karthief]

Have you looked at the PS pump/sensor?

I was not aware of a power steering pump sensor on our cars?
where would it be located?

 

[vristang]

Thought the 5.0 had them as well, but could very well have that wrong?

Edit…
You are right, the 5.0 didn’t use a ps pressure switch…

 

[Mustang5L5]

I thought CL didn’t trigger until full coolant temp as well, but it has been a while???

That’s how it is on the A9x. Took a peek at the A9x Gfub and there is a min coolant temp required to go into CL. It doesn’t tell me what that temp is, but there are also about a dozen other conditions that need to be met.