Will a blown head gasket do this?

[Eric Stauch]

Hey guys, I took my 87 GN out and was making a few pulls in it and it was running great. Took it home and parked it, next morning I try to crank it and it won't start. If I give it gas it will start but runs real bad. Running down the road it does great. No water in the oil, but car smells really rich. if one is blown between two cylinders could it act like this? Thanks.

 

[Major Nutz]

Sounds like a bad 02 sensor. Were you running any race gas lately?

 

[Boost231]

water could be filling the cylinders when it sits causing it to have a hard start. let it sit.over night and pull thr plugs and take a look

 

[Hotrodbuick]

If water is on top of the piston the starter would probably not start it or it would bend a rod or break a piston. Know this cuz happened to a friend last week. Got water on top of the piston an broke the rod piston an bent the crank. If its white smoking or using water most likely a blown head gasket.

 

[Eric Stauch]

o2 is less than a month old, not saying its not bad though. No race gas and no smoke of any kind.

 

[oldsracer]

How was it running while you were getting on it. What does the scanmaster say

 

[SHADOWII]

Did you check the intake hoses for looseness. Any unmetered air can cause this.

 

[getdowngranny]

Did you check the intake hoses for looseness. Any unmetered air can cause this.

X2. Had this happen to me a few months ago and it had the same exact symptoms you are having.

 

[S10xGN]

Take 20 minutes and run a compression test, that'll tell you real quick if a HG is blown...

 

[Eric Stauch]

it was running great if I really push it hard it will detonate but I don't believe I was ragging it that hard. All intake hoses are tight, I plan to run a compression test but I want to make sure it wasn't a waste of time. How many lbs should the cylinders have? Stock pistons on std. Stock heads.

 

[Ttype6]

it was running great if I really push it hard it will detonate but I don't believe I was ragging it that hard. All intake hoses are tight, I plan to run a compression test but I want to make sure it wasn't a waste of time. How many lbs should the cylinders have? Stock pistons on std. Stock heads.

Do you have a spare MAF?

 

[Eric Stauch]

I do not.

 

[Ttype6]

I do not.

I really think your MAF is bad.You should be able to get a 3" or 3.5" at a salvage yard cheap.
If you want a 3'',tell them you need a MAF for a 1996 S10 truck with a 4.3.
If you want a 3.5",tell them that you want a MAF for a 2000 Camaro with a LS1 motor.
They look the same (aluminum)with different diameters.
They both work well. I recommend the 3.5' LS1.

 

[Ttype6]

Running down the road it does great.

When you're running down the road and it's running great,does it feel like the injectors turn off completely when you let of the throttle?

 

[Eric Stauch]

I have a new 85mm Delphi MAF and a gen 2 translator but have yet to get the wire adaptor for it so I will go ahead and order that and put it on. Hopefully that's all it is. About the injectors cutting off, its really noticeable when I have the exhaust uncapped but mild boost say 5lbs then let off, the idle falls real quick to around 500 but jumps right back up to like 700. Is this what your talking about? Thanks .

 

[Ttype6]

I have a new 85mm Delphi MAF and a gen 2 translator but have yet to get the wire adaptor for it so I will go ahead and order that and put it on. Hopefully that's all it is. About the injectors cutting off, its really noticeable when I have the exhaust uncapped but mild boost say 5lbs then let off, the idle falls real quick to around 500 but jumps right back up to like 700. Is this what your talking about? Thanks .

When mine was bad I could give the car some throttle going up the driveway and the car would stall when I let off the gas. When I would accelerate down the road it was good. As long as I would stay in the gas it ran fine. When I would let off the gas,it was as if the motor shut off and it would eventually come around before I would get to the stop sign. The Idle was not good either.
Did you recently clean and re-oil your filter?
You could try some MAF spray from the auto parts store.

 

[Eric Stauch]

that sounds like mine, did yours idle really bad? mine idles rough and smells really rich.

 

[Ttype6]

that sounds like mine, did yours idle really bad? mine idles rough and smells really rich.

It idled bad. I didn't notice a very rich smell. Maybe because I run E85.
Did you order the adapter harness?
Did you try some MAF spray cleaner?

 

[Eric Stauch]

hey guys sorry I haven't got a chance to update, I cleaned the MAF and swapped O2's neither had any effect. But I did notice the valve cover breathers have a suction. They are not venting out but rather sucking in. If I cap each one with my finger tip it Boggs the motor down.

 

[TurboBob]

thats probably PCV airflow.

at idle and part throttle, the intake system pulls a little bit of air thru the crankcase to keep the blowby vapors from venting to atmosphere. The PCV airflow goes in the breathers, thru the crankcase, and up the PCV valve/hose to the intake. The PCV valve is on the passenger side, beside the intake dog-house and pokes into the base of the intake manifold thru a rubber grommet.


So this is likely "normal". although if the PCV valve is bad, or the wrong one, there may be too much flow....

take a look at the PCV valve and see what kind it is, and if all pieces are in place.

Bob