Hey, I recently changed the headgasket on my saab 9000 cse 2,3 turbo 1997 and after that the car has been leaking water from the top of the exhaust manifold. It doesnt seem like it is loosing coolant. Is this just leftovers from when the headgasket was blow? Just to be clear this headgasket was really bad I almost mistook the car for a steamtrain. 1st sylinder was filled with water almost all the way. I would also like to add that the car is not in daily use so it has not been driven anywhere after the new headgasket. It has only been started for about 10 minutes every now and then. The car also drinks alot of fuel i can see the needle move and will pretty much empty 20 liters after 15 minutes of idle, but ive been told this is because the ecu needs to recalibrate after the battery being disconnected for a long time. Thanks for the help in advance.
I wouldn't stress too much about the water leaking from the manifold - 13% of a gasoline engine's exhaust gas is water vapor. You usually don't see it because it is vented to atmosphere at the end of the tail pipe, along with the other products of combustion. I used to get seriously bummed out when I had done work on the top end of these engines and at initial start-up could see water leaking at the exhaust manifold. But it always cleared up. Let it run for awhile and it will most likely stop visibly leaking.
If it is really bugging you, consider re-torquing the nuts on the head to manifold studs. Saab specs the torque as 25 Nm (about 18.5 ft-lbs), but you could try a just
little bit more. Run the engine up to normal operating temperature, shut it down, back the nuts off somewhat and then re-torque
before the studs can cool down. Torquing manifold studs while they are cold almost guarantees that at least a couple will separate from being over-tensioned when hot. The fasteners and the manifold have different coefficients of thermal expansion.
On the fuel consumption; IDK. That seems like an insane amount of fuel being used - over 5 gallons in 15 minutes - and that's at idle?. The only thing that I can imagine causing that kind of consumption would be a leaking fuel line - either in the return or supply piping. But if that were the case, I sure you could easily smell the gas.
Another remote possibility would be that the diaphragm in your FPR (fuel pressure regulator) is ruptured thus allowing gas from the injector rail to enter the control vacuum hose. In that scenario, fuel (at about 45 psi) would be allowed to flow through the broken diaphragm, into the control hose and then be dumped into the intake manifold. Also since you are only at idle, the turbo charger is just rolling over so it's unable to pressurize the intake system. Even if it were spun up, It wouldn't matter because the throttle plate is completely closed. End result is that the gas is being forced into the manifold and also being sucked in because the intake system will be at it's lowest pressure.
After that, it's into the combustion chambers and then out the exhaust without the fuel being burned. When this happens, fuel pressure regulation is skewed causing excess fuel consumption.
Or maybe you have really bad luck and all 4 of your injectors are stuck wide open. The maximum design flow rate for these nozzles is 350 ml/min = 1400 ml for 4. If all 4 of them are constantly and completely open, the total volume of fuel that could flow through them in 15 minutes is 21000 ml (1400 ml X 15 min). That is about 5 gallons.
You can try to do an adaptation run. I've never had to do one. I have done them after making changes to the APC system. It was usually just to return the boost pressure to where it was before the repair was made. Honestly though, I never got the feeling that the procedure really did anything. It did get me an $283 speeding ticket once. Procedure is below:
Adaptation of maximum boost pressure is carried out continuously during normal driving. If the Trionic control module is removed or anything else is done which affects the adaptation level, it is possible to speed up adaptation and so attain maximum performance faster by carrying out adaptation of the system as described below.
IMPORTANT: The engine should be thoroughly warmed up. Basic boost pressure should be correctly adjusted. Use fuel of good quality and a high octane rating.
Cars With A Manual Gearbox
Accelerate at wide open throttle in as high a gear as possible from about 2000 rpm up to 3500 rpm. Since the minimum time for passing the adaptation range (2750-3250 rpm) should be longer than 3 seconds, it is best to carry out adaptation on an uphill gradient. Repeat the procedure until maximum nominal boost pressure in regard to the fuel grade used, etc. is attained.
Cars With Automatic Transmission
Accelerate at as wide a throttle opening as possible without activating the kick-down function, from about 3000 rpm up to 4500 rpm. Since the minimum time for passing the adaptation range (3750-4250 rpm) should be longer than 3 seconds, it is best to carry out adaptation on an uphill gradient.
Repeat the procedure until maximum nominal boost pressure in regard to the fuel grade used, etc. is attained.
IMPORTANT: If the pressure switch opens repeatedly because boost pressure is too high (due to a defective boost pressure control valve, for instance), maximum negative adaptation will be obtained. As a result, maximum boost pressure will not attain its normal level. To restore maximum boost pressure to its normal level, disconnect and reconnect the control module and carry out adaptation as described above.
