This really sounds like your running out of fuel. an engine will back-fire as it goes lean. I would start by replacing the fuel filter, it's just maintenance anyways, and if that doesn't solve your problem you may have a bad fuel pump. It would be a good idea to have the fuel pressure checked under load before replacing it though as they are expensive. I would hook up a fuel pressure gauge and tape it to the front window while driving. If you can't do this, see if you can find a shop that will. They won't like taking instructions from you, but this is an important test to determine if the pump can prvide the volume the engine needs while under boost. The fuel pressure should be 28psi at idle and should rise to 42 psi under boost. If it can't sustain 42 psi under boost, you have a bad fuel pump.
Hope this helps,
Dave
Hello.
My suspicion on your problem is a plugged exhaust or slipped crankshaft to camshaft timing.
I'd bet on the exhaust though.
It appears your turbo is doing it's job as it is able to blow off the intake duct.
But if all that pressure can't get out the other end it's bound to do that.
Drill and tap a small fitting into the exhaust pipe behind the exhaust manifold and install a pressure gauge there. Should not be over 1 PSI at idle and not over 2 on throttle blips.
Hope this solves your problem.
If you need more help with this, ask me.
KL
The higher the speed the more veloctity will
be pulled OUT of that cowl opening...... those rear opening cowl hoods are ment
to **** air ( THE HOT AIR ) out ! not in .
Acording to the procedure.The hood is fed by
the positive pressure created at the base of the windshield. The 'hood' system
starts to become effective around 35+ MPH by providing good clean but more
importantly, cooler air. Cowl induction systems work well if put together
properly. Usually there is a air box that fits under and around the air filter
assembly and seals to the hood when closed. That isolates the air filter from
the hot engine air and allowing the carb or TBI to pull air while the cowl
opening pushes cold air . Thats the idea.
TBI Throttle Body Injection is a very versatile, highly adaptable form of electronic controlled mechanical fuel injection. TBI provides the optimum mixture ratio of air and fuel at all stages of combustion. TBI has immediate response characteristics to constantly changing conditions and allows the engine to run with the leanest possible air / fuel mixture ratio, greatly reducing exhaust gas emissions. Because it's air / fuel mixture is so precise, based upon much more than simple engine vacuum and other mechanical metering means, TBI naturally enjoys an increase in fuel economy over a simple mechanical form of fuel introduction such as a outdated carburetor.
The TBI form of EFI is controlled by the ECM (Electronic Command Module) which controls the TBI based EFI system through all stages of operation according to data received regarding the current state of engine performance, speed, and load. The main component of this system is the TBI throttle body injector, which is mounted on top of the intake manifold, much like a carburetor. The throttle body injector is composed of two different parts; the throttle body itself, and the injector assembly. Hard to understand, isn't it? The throttle body is in fact, a large throttle valve, with a pair of linked butterfly hinged flapper valves, which are controlled by a simple mechanical linkage to the accelerator pedal. Depressing the accelerator pedal will force the throttle valve to butterfly open further and further, increasing the flow of air through the throttle valve and instructing the ECM to add more fuel, thus producing more power, faster speed, and acceleration.
Attached to the body of the TBI unit are two sensors; the TPS throttle position sensor, and the IAC idle air control assembly. The ECM uses the TPS to determine the accurate position of the throttle body valve, it's degree of cycling, and how open it is (0% to 100%). The ECM takes readings from the IAC in order to maintain a constant idle speed during normal engine operation, during all stages of power, load, and combustion.
The fuel metering assembly contains a fuel pressure regulator which dampens the pulsations and turbulence generated from the very high pressure fuel pump. Think of the FPR as a conditioner that smoothes out the flow of fuel from the outside to the inside of the fuel metering assembly. The FPR also maintains a constant, steady pressure at the injector assembly. Dual fuel injectors are mounted over the throttle valve, synchronized, and raised slightly over a venturi (narrowing radius) throat. Each injector is controlled by the ECM through an electrically initiated solenoid (switch). The precise amount of fuel delivered by each injector is varied by the amount of time that the solenoid holds the injector plunger open for operation.
A high pressure, high volume electric fuel pump is used with the TBI system. This pump is located within the fuel tank itself (which can be a PITA if you have to replace it). Once the ignition key is inserted into the ignition, and the ignition moved to the RUN or START position, the fuel pump relay instantly initiates the pump, beginning the transfer of fuel (via the pump) from the tank to the injectors. A safety relay in the system shuts the pump off after two seconds, to keep the fuel from flooding. Failure of the fuel pump relay will allow the fuel pump to operate only after four pounds of oil pressure have built up. A high capacity fuel filter, similar to an in-line variety, is located on the left side of the vehicle, at the rear of the engine.
Two common mistakes when working with the EFI system. The fuel system is pressurized. If you remove a fuel line, you could/will get a face full of fuel! The fuel pump used on the EFI system is much more powerful than that found on a carburetor installation. For this very reason, the second problem is that you cannot use a EFI fuel pump to feed a carburetor, and you cannot use a normal carburetor mechanical style fuel pump (low pressure) to feed a EFI system. In order to work on any part of the EFI system, you must first depressurize your fuel system!!!!!
This will
help. Thanks please keep
updated.please do rate the solution positively .thank you for using fixya
I'm assuming you have correctly assembled everything back together. In that cast the oil can come from just one source: the bearings of the turbo. This is a major failure, the turbo must be remanufactured.
The tube pops because the pressure is too high - the PCV and the wastegate don't do their job. Adding to the fact that you think the fuel ratio is too weak , all this makes me think of a ECM (or the cables leading to it) failure.
Have the timing checked on this car and replace the fuel filter, if the spark plugs appear whitish in color it would indicate lean mixture, also you may want to replace the primary or bank one Oxygen sensor located before catalytic converter this sensor controls air/fuel mixture. Next check would be ignition use an old trick I found useful, at night or in a dark environment aquire a spray bottle with water and proceed to spray the spark plug wires and distributor cap then have an assistant rev up the motor as you look for any blue sparks coming out of the wires or distributor cap if you see this replace spark plug wires and cap and rotor.
Good luck
Change the fuel filter and diverted valve, and clean the airflow sensor to get rid of the stuttering. A clogged fuel filter is a chokepoint for the engine especially when the turbo comes into boost and the engine's fuel demands ramp up to compensate for the extra airflow. The diverted valve shunts boost air back into the intake stream when you lift off the gas (such as when you shift), and it uses a manifold pressure reference. If the valve is bad (and the internal plastic diaphragms do fail more often than you'd want), the valve can open or leak even when you are on the gas. This will cause the boost and power to fall off and can initially cause the car to run rich, which will cause rough running.
It definitely sounds like you have a vacuum problem. Check and replace the plastic ports, check and replace the rubber bushings in the intake manifold. I would use a slightly smaller vacuum line like a 5/32, spray it with a little brake cleaner prior to putting it on and that should eliminate it "popping" off. You can check for vacuum leaks by spraying a little carb cleaner (with the engine running of course) where your lines connect, and any other suspect areas, or if your not comfortable with spraying carb cleaner you can spray a little water instead and listen for any idle changes. Any hoses that seem softer than normal or with a lot of oil on them should be replaced. Check all hose clamps/connectors and make sure they are tight. I hope this helps you out. Good luck.
First off ill guess that you have already tested the fuel pump for proper presure, so on that assumtion i would check the presure regulator and also pull the injectors to make sure that you have a good spray pattern, also do a compression test on the cylinders to make sure you are getting good compression and not leaking past a valve. I would also check the spark plugs they can tell you alot about how the car is running ... chart of what to look for on spark plugs
Try checking for a partially resticted catalytic convertor, by using a perssure gauge on the oxygen sensor thread. They sell or rent the kit for this. Or you could check for weak exhaust and excess pressure at the oxygen sensor by feel.
If the hoses are being blown off, you are getting too much boost. And the wastegate is supposed to prevent that. Which is why I suggested a restricted exhaust system from a partially plugged convertor. But you should see the wastegate in operation. Perhaps it is not adjusted rights. Change the length until there is almost no boost, and then slowly adjust it until it runs bad or blows off. Then you will know the range and figure out the optimum.
http://www.elkparts.com/saab-93-m98-to-02/performance-tuning/special-products/forge-motorsport-adjustable-wastegate-actuatorbrsaab-93-viggen-93-aero-95-aero.p3223.html
×
Have you been able to test the mass air flow sensor or even look at the spark plugs. You may have electrical leaks at the insulators or a bad mass air flow sensor. Have you looked under the vehicle after it has warmed up to see if the catalytic converter is red hot?
Check the intake for leaks.
a can of carb spray will help out a lot
spray the parimeter of the intake with carb spray with the engine idling. if the rpm increases when spraying, that means the gasket is leaking sucking in air and blowing oil through your tbi
Remove the fuel filter,then try and blow threw it to see if you can blow threw it with your mouth,if it is at all hard to blow threw,replace it,if this is not the problem,have the fuel pressure checked,it is possible that the fuel pump is weak.
Yes,it is to have vacuum,if it does not,remove the throttle body,and clean the carbon build up,out of the port holes and such,then ,when you are back together,and running good,use some sea foam ,to clean out the system good,it comes in a can,use a vacuum hose,to the pcv inlet,and let it **** in the sea foam from the can to deep clean it.
Have the fuel pressure checked ,it is most likely the problem if the fuel filter is not clogged up,or restricted.
By the way,in my text,they used some ****** in place of a word I used,it was not a slang word or anything,but it means vacuum,so,just wanted to explain,I do not use foul language.
×
2,426 views
Usually answered in minutes!
is the tbi supose to have air sucked into the tbi where the pvc check valve hose goes?
×