81'x FI Struggles, shut down with black smoke

81x

81x

X'ing Fixing
Hi,
My X continues with the challenges.
Few weeks ago I took it for a quick ride, when I was backing into the garage, it choked and shuted. An attempt to crank it up made black smoke with a strong fuel smell and it didn't cranked.
I already ordered new fuel pump from MWB as mine was noisy and probably failed before, figured it was to blame so I've waited to the package.
In the meantime, I checked and it was cranked immediately and held steady idle, but I didn't try to drive.
I must add that a MWB pre pump filter installed, made the old pump much (much) more quite, but i decided to replace it anyway.

After installing the new pump, I took her out again.
First few minutes was good, after that - the same symptoms as before, now shuted 500 meters from home, had to push it and then roll-start it, struggled with some smoke but made it in the garage.
And same as before - immediate cranking would not succeed but after a day - it started up.

Suggestions on which way to go will be appreciated :)
Thank you.
 
Clearly getting too much fuel. I would imagine if you tried flooring the gas pedal when it does not want to start, it would fire up. But that doesn't solve the problem.

An FI car getting flooded is a strange one. Lots of reasons for a carb'd car to do it... but FI, odd. I would start with ensuring the fuel pressure regulator is functional, and the vacuum line running from the intake plenum to it is in good shape, no holes or cracks.

Putting a small fuel pressure gauge on the pressure (pre-regulator) side of the line tells a lot. It's fairly easy to plumb one into the line that goes to the cold start valve (that blue thing on the side of the intake plenum "log".
 
As well as Pete's suggestions I would suggest its getting its signals mixed up and so possibly over fuelling when the engine clearly doesn't need it. Throttle position sensor and air flow metre spring to mind
 
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This happened to me. Turned out the O2 sensor came unplugged. If your O2 sensor is not plugged in, your car runs very rich as if it is cold. So, when it heats up, way too much fuel and it will only sputter.
 
Thank you all for your ideas. A friend with identical car will come with parts that mentioned for a little test.
For the O2 Sensor, could you please point for its location?
 
Yup, center of the engine, look down between the intake manifold and the rear trunk wall. On the exhaust, you will see it stick out.

Make sure you get an O2 tool, makes life much easier.
 
Thanks!
Is it possible without one?
What it's size? Incase I'll need to buy or fabricate it.
 
81x, have you checked your fuel pressure regulator like Pete Whitstone suggested? I strongly encourage you to do so if you haven't yet. On my 1986 X1/9 the fuel pressure regulator was faulty when I bought the car. The internal diaphram in the fuel pressure regulator failed and there was raw fuel entering the vacuum side allowing fuel to be dumped into the intake manifold. It caused the intake manifold to ice up it was so bad. The symptom was that the car started good when cold but was very hard to start when warm and when the fuel pressure regulator got really bad it didn't idle properly either due to the excess amount of fuel entering the intake manifold.

Good luck with getting your problem resolved. Keep at it in a logical and systematic way and you will come out on top. Let us know how you make out.

George
 
Thank you, George.
I will give it a check, just need to clear some time to go there. Besides connecting a pressure gauge, is there another way to check it?
I'm starting from the easy part to diagnose and move on to the difficult one, i live far from any vendor so have to be accurate.
Will be updating, ofcource.
 
So the O2 sensor seems in place and not damaged, wire too.
How can I test it for failure?
The plug cover broke in my hand while jiggle with it gently, but the inner connection seems ok.
The sensor wire joins a group of wires in a plastic sleeve, and one of them ends with a loose plug.
Where it's suppose to be connected to?

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Another issue i noticed, the metal tube coming from the fuel filter "sweats" fuel in the connecting point to the rubber tube, can it give an idea for the problem?
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A basic test is that you can pull the vacuum line off the fuel pressure regulator and sniff it. Typically, when they fail the diaphragm will tear & allow fuel to be suctioned into the engine.

That connector you circled is a test connector, not connected to any device/

You can pull back the black boot on the oxygen sensor wire where it plugs into the green wire. Using a voltmeter on low scale, it should read a varying voltage when hot of under 1v. If it does not sweep, it is likely dead. They are intended to be replaced every 30K, it is considered a service item, not life of the car...

The coolant temp sensor for the FI will also make the car run really rich it is bad, and/or the harness/connector terminals are corroded.
 
Disclaimer: The FI troubleshooting manual in the wiki is ALWAYS the best way to diagnose your FI woes.

Having said that, this sounds like a coolant temp sensor issue to me. The T/S shows you how to check this---all you need is a multimeter because all you are checking is resistance cold vs resistance hot. Fi4.jpg (700×855) (xwebforums.com) Do follow the advice to check resistance at the plug connected to the FI controller, because this checks the sensor AND the wiring at the same time.

If the test leads you to believe that the CTS is sending too much resistance to the FI controller making the controller think the engine is always cold and thus getting waaaay too much fuel, you can fool it into thinking its fully warmed up (and not in need of too much fuel) by jumping the two connectors in the plug that plugs onto the CTS. If doing that clears up the problem then try a new CTS. They are very common to zillions of Bosch L-Jet cars so aftermarket versions are pretty inexpensive.
 
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That last photo of the rubber fuel hose connected to the fuel filter with that style worm drive metal clamp (Jubilee clip) "sweating" is a fire hazard. Google "fuel hose clamps", cheap insurance against catastrophic loss.
 
81x, just as Hussein said, pull of the hose on the vacuum side of the fuel pressure regulator and smell/look for any signs of fuel. If the diaphram has failed in the fuel pressure regulator you should at the very least smell fuel if not see wet fuel present when you remove the hose from the vacuum side of the fuel pressure regulator. This however will not assure that your fuel pressure regulator is functioning properly in regards to maintaining the correct fuel pressure. You need to check the fuel pressure regulator with a vacuum gauge to assure that it is maintaining the correct pressure.

Like moto trooper said, that worm style hose clamp on the rubber fuel line needs to be replaced immediately. Never use that style of clamp on any fuel hoses! Also, Dan is right on with recommending that you following the fuel injection diagnosis troubleshooting manual. This manual is very well written and very easy to understand and follow. You will save a lot of "chasing your tail" if you follow this manual religiously.
 
As usual, a lot of detailed info, thank you all.
Every suggestion will be checked.
Hope I can reach that in the next few days.

For the clamps, I saw 2 types, which one will be better?
That one looks somewhere like the original clamps but probably require a special tool
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That one looks more common and for sure I can find at a local hardware store
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Both seems to do the same action, like "hugging" the hose, am I right?
 
On my '86 with FI, the original fuel system used the top style of clamp, called Oetiker clamps, only on the non-pressurized fuel vapor hoses of the fuel system. My car still had the original-to-the-car fuel injection hoses on the pressure side of the system, and the majority of those connections did not use any sort of clamp.

If you are looking to repair that pictured leaking connection, then your best option IMHO is to acquire some of the lower type of clamp--these are often stocked in local chain parts stores and are colloquially know as "fuel injection hose clamps." They have the advantage of being able to taken apart (unscrew the screw) so that you can replace an incorrect open slot worm gear clamp without pulling the hose off the barb or nipple. An acceptable substitute would be a shielded/lined worm gear clamp, the design of which never exposes the rubber of the hose to being extruded thru the worm drive slots. Example: Precision Brand B20HL Shielded/Lined Worm Gear Hose Clamp, 1-1/8" - 1-5/8" (Pack of 10): Amazon.com: Industrial & Scientific
 
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