bad news here, could use help diagnosing

[Austin06]

Well, after having some issues with my car not running or ideling....did some standard tests and this is what I found...
Compression test was done on a cold engine, since I couldn't run the car long enough to get it to operating temp..........
Cylinder 1 - 4..........120-125-105-140

Not good, I know. so now on the leak down... I used the compression tester hose, removed the sharder, and feed in roughly 20 psi through each cylinder, with all plugs removed. Set cam timing to TDC and went from there, and this is what happened..

Cllinder 1 - 4

1: had air leaking out the oil cap
2: coming out the exhaust
3: the IC piping, also found a nice leak at my TB
4: out the oil cap

So, after seeing all that, i thought to myself, maybe the timing is off. But I'm pretty darm sure of myself, that the timing is right. I can post pictures is needed.
Let me know if you need more information, I just need help in solving the mistery of this thing...haha

 

[Locke]

When you do a leak down test, you must have the cylinder you are testing at TDC. Did you do this?

-Set #1 to TDC, test #1.
-Rotate the crank 180 degrees (which places #3 at TDC) and test #3.
-Rotate another 180* then test #4.
-Rotate 180* and test #2.
-One final rotation of 180* will place #1 back at TDC.

 

[schoffs4]

burnt valves but it should start with that comp readings

 

[Austin06]

I will make sure I do that this time, although I did all cylinders with #1 at TDC.

 

[fourreGsixty3]

No wonder you has air coming out the exhaust, and intake...the exhaust valve on #2 were open, and the intake valve on #3 was open, thus allowing air to escape. All the cylinder's on our engine are on different strokes. Intake stroke: piston sucks air down into the cylinder through the intake valve. Compression: piston moves upward's, and compresses the a/f mixture. Power stroke: the piston is forced down from the burnt fuel mixture. Exhaust stroke: piston moves upward's again forcing the spent gases out the exhaust valve. With compression test's they are preformed when the piston is on the compression, or exhaust strokes. With #1 either your ring's are worn( good possibility depending on mileage), or there is a hole in the piston( not probable), and same with #4. Do exactly as Locke stated...I would have told you the exact same thing. Do not be disheartend by the compression readings you have with the motor cold. The reason for them being so low is because the piston is not matched perfectly to the cylinder, it is in fact egg shaped, and the heat allow's it to expand, thus giving you an accurate reading. Also make sure you crank the engine over the same amount of times for each cylinder. Also you will want to look into ignition/fuel for your non start problem's. If you arent getting either it obviously won't start.

Hope this helps you out in clearing the air.

 

[jamisonj24]

I would'nt worry about a leakdown test yet. You should get your car running first then do a compression test with a hot engine. Your cold engine compression numbers don't mean squat, unless they were extremely low.

 

[Austin06]

No wonder you has air coming out the exhaust, and intake...the exhaust valve on #2 were open, and the intake valve on #3 was open, thus allowing air to escape. All the cylinder's on our engine are on different strokes. Intake stroke: piston sucks air down into the cylinder through the intake valve. Compression: piston moves upward's, and compresses the a/f mixture. Power stroke: the piston is forced down from the burnt fuel mixture. Exhaust stroke: piston moves upward's again forcing the spent gases out the exhaust valve. With compression test's they are preformed when the piston is on the compression, or exhaust strokes. With #1 either your ring's are worn( good possibility depending on mileage), or there is a hole in the piston( not probable), and same with #4. Do exactly as Locke stated...I would have told you the exact same thing. Do not be disheartend by the compression readings you have with the motor cold. The reason for them being so low is because the piston is not matched perfectly to the cylinder, it is in fact egg shaped, and the heat allow's it to expand, thus giving you an accurate reading. Also make sure you crank the engine over the same amount of times for each cylinder. Also you will want to look into ignition/fuel for your non start problem's. If you arent getting either it obviously won't start.

Hope this helps you out in clearing the air.

Well, unfortunately I'm not trying to sound like a newbie here, but it isn't working , because I really understand how gas/diesel engines work...I do it for a living.
But, I've never had to diagnose something of this sort before, leakdown test being one of them. I was also unable to find a good write-up on it.
Well the problem really is that it won't idle, it will start and run like shit if I keep on the throttle. Seems to backfire, pop, and small clouds of grey smoke. I've started with the obviously....plugs/wires. Both are new.

But, I can't get this out of my head....car was basically stock, before new head and gasket with ARP's, stock cylinder head, new turbo and fmic setup, and topped off with revised lifters and a set of DKS 272's. Now all I wanted to was have the car run on stcok 450's so i could set timing, then purchase what i need to run my 850's and have it tuned. Somehow I've convinced myself that, that is the problem, but I'm just not sure.
Could that be my main problem, or is it just the cams throwing things off?

 

[fourreGsixty3]

Bluish grey smoke mean's valve seal's, ring's, or turbo seal's. Did you have the head checked for flatness( is this a word)?

 

[Austin06]

Pretty sure it's not bluish grey, more like just grey. You can small fuel hardcore.

BTW: 4 strokes of a 4 storke engine.....suck,squeeze,bang, and blow.

 

[kenamond]

Check the CAS. Mine started acting up - would act just like you're saying. But I could get it to work again (see below). But the first time it did it, I got no CEL until AFTER the car ran normally. Don't know if the 1g is the same w.r.t. the CEL phenomenon. Anyway, the CAS is easy to access on the 1gs like it is on the 2gbs (2ga CAS is hard to get to). Link at the end of this post has pics. I found that pulling the plug, blowing hard into it (the plug, not the CAS), then reconnecting it firmly with a bit of wiggling would make it work for a day or three until I got the new CAS installed. Mine cost $80 at Autozone. Probably the easiest thing I've ever replaced on my car.

http://members.shaw.ca/dsm.1000q/Engineprimer/1G/cas.htm

EDIT: In the picture, the sensor is actually a small thing bolted to the top with the plug sticking out of it. 2 bolts on a 1g and 1 bolt on a 2gb. That plug is what I'd fiddle with.

 

[10's or bust]

Also check for boost leaks and make sure there aren't any....

 

[Austin06]

Well after squeezing in sometime to work on the car, this is what i found when i re-did the leakdown test.

I stopped with cylinder 1...

When i placed cyl. 1 at TDC according to the balancer marks, and also rechecked with a screwdriver to verify, I applied roughly 25psi in through the plug hole with the proper hose adapter and had air gushing from cyl 2.

So did I do something wrong, or is my cylinder head f'd?

 

[Locke]

Blown HG or cracked head. The head gasket will tend to go before the head, so there is a decent chance it is just the head gasket. Either way, you will find yourself removing the head for inspection and repair.

Get to it, then!

 

[Austin06]

Well the thing is that i picked the head up used from a member on this board. When I installed the head, with a new cometic head gaskets and ARP studs.

 

[cbassgsx]

did you deck it?did you check the cas for assbackwardness. that'll make it run bad and smell fuel.

 

[Austin06]

did you deck it?did you check the cas for assbackwardness. that'll make it run bad and smell fuel.

Thats a negative on the decking. I'm actually not exactly sure what you mean by that.
And I set the CAS properly according to the timing marks and whatnot.

 

[Austin06]

Well after doing some searching and reading here...

Looks like the cometic install without decking the block/head, probably didn't seal properly.

What do you think?

I think I'm just gonna swap back to the Mitsu felt gasket.

 

[adidalax]

If you got that thing used, you don't know what it's been through. Heads come off of cars warped all the time, thats why when you replace a blown head gasket, its usually a good idea to re-deck the head to assure that it will seal correctly. Aluminum can be very prone to warp if it heats up enoguh.

I'd say if you didn't have the head decked & are using that harder Cometic gasket, that's got to be the issue. Don't forget that oil passages run through the head gasket as well, so that may be why the air was escaping through the oil cap.

IMHO - it needs to be decked. Also - don't blame the head gasket, I hear great things about the Cometic's. You just need to make sure you do it right. Get the head re-decked & buy yourself another Cometic so you are sure it gets a good seal...

 

[Austin06]

If you got that thing used, you don't know what it's been through. Heads come off of cars warped all the time, thats why when you replace a blown head gasket, its usually a good idea to re-deck the head to assure that it will seal correctly. Aluminum can be very prone to warp if it heats up enoguh.

I'd say if you didn't have the head decked & are using that harder Cometic gasket, that's got to be the issue. Don't forget that oil passages run through the head gasket as well, so that may be why the air was escaping through the oil cap.

IMHO - it needs to be decked. Also - don't blame the head gasket, I hear great things about the Cometic's. You just need to make sure you do it right. Get the head re-decked & buy yourself another Cometic so you are sure it gets a good seal...

So your saying it wouldn't have anything to do with the block then?

The only reason the head even came off in the first place was because a stud snapped and took the coner off with it.

Looks like its all coming apart again.

 

[adidalax]

i'm saying the head is more likely to warp than the block, that's why its usually good measure to deck a head before you put it on - especially if it's used....

 

[Austin06]

Alright man, thanks for the info.

Looks like I know what I'm doing tonight....along with a 12 pack.