Need Input on KA with Vac Leak

[Burnsey]

okay ... my car is a NON TURBO ... KA24DE ... why did I post it in KA-T? ... read on.

Okay I've had a project car for coming up on a year now, anyways I've replaced a lotta stuff and yada yada yada ... I have even deleted all the vac/emissions junk and its come down to a leak, I finally got a hold of my brothers boost leak tester he uses on his SRT-4 ... so I took the MAF off and hooked it up and tried pumping it to 4-6 psi in order to find my leaks. so I found a few and its finally going up to about 6 psi ... but leaking still ... I had my hand down around where the oil pan meets the block and sure enough

So I guess what I need to know ... is

A.) Should the pressure be reaching down to the oil pan or is that normal

B.) Is this a sign of worn rings? ...

C.) Am I even testing it correctly? ...

I'm not very mechanically inclined and usually have a member (KATwo40) around to help but wasn't able to talk to him today ... Anyways I'm on the brink of finally driving this thing and gettin on with the turbo kit so any help/input would be awesome... I have searched and can't really find anything concrete, plus I'm really tired and worn out after all the work on the car today.

Car is:1989 240sxDOHC (OBD I - 1991 engine)Manual transmission

Thanks in advance.

[C-Kwik]

To clarify, you do not have a turbo? If not, then is the breather tube from the valve cover attached to the intake? Pressurizing the intake with this connected would surely pressurize the crankcase, which you should not be doing.

If you have a turbo, this line would normally be connected in front of the turbo, but defintely, never to any part of the intake that sees pressure.

Sounds like you may have damaged the oil pan seal by doing this. Possibly other seals as well.

[Burnsey]

well haha you got it! thanks man.

[jmwenick]

I've had to boost leak test without a turbo also, just hook it up straight to the throttle body, then open the throttle and pressurize, you'll find the leak.

[Burnsey]

...is the breather tube from the valve cover attached to the intake? Pressurizing the intake with this connected would surely pressurize the crankcase, which you should not be doing.

whoops ... I did <-- told you I wasn't mechanically inclined!

...Sounds like you may have damaged the oil pan seal by doing this. Possibly other seals as well.

the engine is a DOHC which I've replaced everything on except for o2 sensor, and internals (pistons, rings, etc) ... when I start it up ... it smokes a lot and also goes into the limp mode (getting a new MAF might fix that ... but I've already been through 1 new one already) ... anyways I'm thinking the rings might be worn because it smokes so badly? and ... I prolly didn't help things pressurizing the crankcase, eh? haha - whoops.

I've had to boost leak test without a turbo also, just hook it up straight to the throttle body, then open the throttle and pressurize, you'll find the leak.

I guess I'll try and reseal the oil pan and go at this .... Would I need to take it off all the way you think, or maybe just jam some sealant in there and hope for the best (I don't have my engine hoist at my house to pull up/out the engine)

[WDRacing]

When I tested my car for leaks, I only tested the IC and plumbing. I didn't have the motor hooked up. To many variables involved with the motor, valves open or closed etc.

WD

[Burnsey]

When I tested my car for leaks, I only tested the IC and plumbing. I didn't have the motor hooked up. To many variables involved with the motor, valves open or closed etc.

WD

I don't have an intercooler or plumbing yet

As soon as I get the mr2 as my daily driver ... the 240 (which will hopefully be running) will receive a few more suspenion upgrades followed by the turbo.

[Edub1]

What do you mean "replaced everything"?

Smoke on startup is often a sign of bad valve guide seals. I just did a write up on replacing them. But going into limp mode, that doesn't sound good.

Can you give more info on what you did and what is happening?

[Burnsey]

Like water pump, radiator, radiator hoses, revised intake manifold via FIZNAT's write up (which was a HUGE help, thanks), all new vac/heater lines, thermostat, head gasket, intake gasket, exhaust gasket, throttle body gasket, IACV gasket, EGR seal/block off plate, front and rear seals, valve cover, timing chain - guides - and tensioners, new intermediate sprocket, spark plug wires, MAF, intake, cat was clogged so I gutted it, changed out all the interior, replaced with black mint condition interior, took out all sound deadening and put new deadener in place, new (used) tachometer, new clutch kit, took off clutch fan and mounted two 12" electric fans with adjustable thermo to the radiator, new tie rods innner and outter, new lower control arms on the way, I'm sure there's more I'm missing .... I mean I've replaced A LOT of stuff on the car ... except for ...

the o2 sensor - which seemed to still be in great shape

and I haven't replaced any pistons, rings, etc (haven't touched the internals) - although i think we looked over the engine with valve cover and oil pan removed etc. -- KAtwo40 can correct me if I'm wrong (he's my mechanic sorta haha)

This car is a 1989 fastback and I have swapped in a 1991 Manual ECU transmission with engine --- all of which had ~100,000 miles on it. (did all the work to it after i got it)

and i KNOW all my wiring is done properly for the swap's sake so its not an error there ... it starts up ... just does not properly

[Neejay]

What do you mean "replaced everything"?

Smoke on startup is often a sign of bad valve guide seals. I just did a write up on replacing them. But going into limp mode, that doesn't sound good.

Can you give more info on what you did and what is happening?

Is the guide for SOHC or DOHC? And can you give the link to it? I tried searching for it, but couldn't find it.

[Edub1]

zerothread?id=200681

Both motors should be the same but you will need 8 exhaust seals for the DE.

[Edub1]

No valve job? Have you tested compression? How much smoke?

Limp mode is something though. A bad MAF or perhaps other sensor will do that. I'd consult the online mechanic or at least scour the FSM. a bad vacuum leak might do that too. You have messed with so much...

[Burnsey]

No valve job? Have you tested compression? How much smoke?

Limp mode is something though. A bad MAF or perhaps other sensor will do that. I'd consult the online mechanic or at least scour the FSM. a bad vacuum leak might do that too. You have messed with so much...

Yeah I tested compression, all came out good ... i think it was 160's or 180's ... can't remember haha ... just know it was good accross all 4 cylinders

I'll be sealing the oil pan up tomorrow (hopefully) ... and then be testing my car using a different MAF (s14 stock MAF) from a friend that's here in town, but that'll be saturday.When you say ... "messed with so much" ... do you mean in a bad way?

[Burnsey]

okay ... apparently the S14 and S13 have different plug types for the MAF ... therefore I will not be able to use that one.... I'm going to try and get one for the s13 tomorrow to try out real quick.

[KATwo40]

I have a good S13 MAF for you.

[Edub1]

The more things done the more things to suspect.

You should really study the FSM diagnostic proceedures and see what you can do with a digital volt meter. You should be able to test the MAF and all the wires without actually replacing it.

[Burnsey]

I have a good S13 MAF for you.

Tried it out today. still runs like poop. I left you a message on ur cell. do you think you could come over and take a look at the cam sprocket tonight?

[Burnsey]

FIXED ... this part at least haha ...

Problem WAS --> The cam sprockets were off by a tooth or so. fixed that ... now it runs and the airhorn type noise is gone, and revs up to redline, beautifully.

However a new one has risen... When i took it around the block a time or two it was pulling strong and what not. it was doing awesome. when I pulled back in the driveway to park it ... it RANDOMLY revs full blast (up/beyond redline) - or tried to until i shut it off immediatly.

I went to the engine bay to check the TB and it was closed all the way ... and now whenever I try to start the car ... it does that? ... the gas pedal is not pushed down/stuck ... its up in its normal position.

any ideas on that one?