nord

Ok,so 10 point to you!
Did a final search tonight so i know what to order tomorrow..Tried starting with vaccum hose pulled of the front damper and FPR.
It's flowing fuel from the vaccum connection on the FPR so it looks like i've found the problem,Thanks!

nord

Hi!
So i'm about to go insaine..
Got my new dampers and FPR but still not working.(no more fuel in vaccum lines.)
Did also try and pressurize my intake but could not hear any leak's,guess it would have to be one big leak to cause this much trouble.

To summaries:

Compression=good
Timing,timing belt=good
Relay's=good
intake leaks=good,i think.(no really big one's)
Spark=good,new plug wires,rotor's,rotor cap's,spark plugs.
Fuel=sparkplugs are wet with fuel.

Parts recently changed are:
Knock-sensors,idle-stabileser,seals/gaskets and vakum-lines under intake,o2 sensor and temp 2 sensor..(before i had this problem)
sparkplug's,rotor's and cap's,FPR and bouth dampers..(yes fireing order is correct.)


If i try to star it start's and rev's up to 3-4000 rpm then dies.
If i try to start with MAF disconnected it will run and idle at about 2300 rpm for as long as i want.(exhaust smells really rich)
Her is a video with MAF unplugged.


Any idea's anyone what this problem could be?

Mrmerlin

did you get the correct dampers and FPR and are they installed in the correct positions?
FPR goes to the right rear,
fuel rail dampers go to left rear fuel rail ,
and to the center front of both rails above the water pump

nord

Yes,they are the correct parts and correct installed.

jcorenman

Does it rev by itself (no throttle), or do you give it some throttle?

With the MAF connected, does the exhaust smell rich when it dies?

Have you tried a different MAF?

nord

Yes,it rev's by itself and no it's is not a problem with throttle vaier.
I don't have another MAF i can try.

nord

Any good ideas wher i should start searching next..?

jcorenman

Well, when all of the likely possibilities are eliminated, then it is necessary to consider the unlikely.

It is certainly possible that this is a MAF problem. Normally, they age very slowly and will read a few percent low, causing the mixture to be a bit more lean. However, they can fail in other ways which produces an incorrect signal, causing the fueling to be incorrect.

So, with the MAF connected, if the engine stalls and smells rich, then I would definitely suspect the MAF. Either swap it for a spare that is known to be good, or send it to John Speake in the UK for testing.

The other symptom that is unexplained is why the engine rev's to 3-4000 rpm before stalling. If the throttle is closed at idle, then nearly all of the air comes through the ISV, which normally regulated the idle speed. It is not a large opening, and I don't think the ISV can supply enough air for the engine get to 3 or 4000 rpm. Which means that either the throttle plate is not completely closed (perhaps the cable is tight), or there is a large leak. But a large leak would create a lean condition, not rich. And if the only problem was a partially-open throttle plate, then the engine would run fine, just too fast.

Also, have you checked the grounds? Two in particular: the engine-block ground that is located to the rear of the engine on the passenger side (left-hand drive), this is the ground-point for the engine electronics; and the large ground strap under the car, also on the passenger side, from engine-block to frame. This is the main engine ground.

I would clean those grounds first, then check the MAF.

docmirror

Let's review, three things needed for the engine to run. Compression, good - timed spark - good, metered fuel - not good.

The fuel system on these cars is overly complex, and there are a lot of places to have issues. We have two or three indications of too much fuel or fuel pressure. The pressure in the rails should be about 3.8 Bar. The fuel pump will put out around 6 Bar. There is a FPR which you have replaced, now I would like you to check the return line to the fuel tank. It can be found along the rear of the engine bay on the fire wall, and has the line coming off the FPR. Remove the gas cap, remove the line returning to the fuel tank and attach a temp flex hose to it. Blow in the line, it must be free without much back pressure.

If that is returning fuel clear, check the part number on the regulator. It must be 928.110.198.03. It must not be .02, but .03 for 1988 and later. If that is right, I suggest you order a fuel pressure gage from one of the 928 suppliers and install it on the front of the fuel rail. We really need to know that the pressure is right in there. If you can't do that, you could find the idle speed actuator, and the secondary air valve. Both are under the intake, and are a hassle to get to. You would need to just about remove the intake to get to them. Look for a split hose up under there, or a loose hose. If you don't find one of those, you need to get the idle actuator out, and the secondary air valve out and test them.

There's one more thing. At the front of the engine is a tank breather valve. It lets air in and out of the tank and allows the pressure to equalize in the fuel system. You can temporarily disconnect the line to that valve and see if it makes a difference, but it's pretty unlikely as the car doesn't seem to have any time to get any pressure built into the fuel system in your case.

nord

Hi!
Thanks,for good feedback guys.
I will take your advice and check return line,meassure fuel pressure,number on regulator and grounding points.
I'm sure throtthle plate is closed.
What is a PEBCAK...?

nord

Hi again!
ok,so grounding points are good and i will borrow a fuel pressure gauge tomorrow.
Where will be the best point to blow thru my return line?..and can/should i use compressed air..?
FPR has the same number as the old one.
Her is a pic from my car..

Landseer

Were you able to reach them without removing the fuel reg / damper? I never seem to be able to.

nord

Hi!
So this what i found today.
I hooked up a pressure gauge between fuel rail and front damper.
when i turn engine on starter/start the pressure gauge read's about 3,8 Bar...spot on?
Her's some pic..


I still need to blow thru my return line...

Ron.

docmirror

3.8 bar pressure is dead on. You won't need to check your return line if the pressure stays at 3.8 bar. The only reason to check the return line was for an over-pressure problem.

Now, you'll need to check the idle air valve and the secondary air valve. They are under the intake. It's hard to say what will be needed if it were working before the other shop worked on it. If it runs up fast and the throttle isn't open, then the only thing I can think of is the idle circuit, and those valves, but of course it could be another source of intake air somewhere.

docmirror

No google or Yahoo search in Norway? Just type it in your search bar, maybe preface it with "English", and you're good to go.