81'x FI Struggles, shut down with black smoke

A little progress.
I've disconnected the vacuum line, but at the far edge as the edge on the pressure regulator didn't came out easily. no scent or fuel trace where found.
Next test is with pressure gauge only?

For the CTS:
On the manual that @Dan Sarandrea (Phila) posted, it says to pull out the plug from the ECU.
20201017_103732.jpg


Is that gigantic plug?
20201017_102204.jpg


Just loosen those two bolts and pull out?
First time I'm doing it, want to be careful.

The sensor and wires seems complete
20201017_102251.jpg

So dirty o_O

BTW, those are the original clamps I refer to
20201017_104437.jpg

But it those seems to be clamping a non pressure lines.
 
81x said:
Just loosen those two bolts and pull out?
First time I'm doing it, want to be careful.
Click to expand...
There is a metal clip on the right side of that plug. Undo that and the giant plug rotates up and out to the left.
 
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ng_randolph said:
The CTS for the fuel injection system is on the thermostat housing
Click to expand...
The drawing dan posted shows those sensors on the back of the engine, on the other hand the item on MWB website looks like the one i think you refer to (the hex head is thinner). So which one is the correct one?
20201017_214453.jpg
 
The one you just showed with the yellow connector is the correct one. The drawing Dan posted is from the "Fuel Injection Diagnosis" manual. This manual is not specific to the X1/9 (it covers both the 1500cc SOHC engine and the 2000cc DOHC engine), so some of drawings are not accurate for the X1/9.
 
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Just looked back at this:

looks like some serious rust in that lower crossmember area(!) What's the rest of the body like?

20201017_102204.jpg
 
Happy to say that the rest is quite good.
Still at the previous owner, that car was stripped down and welded where needed, can't tell why they skip it.
Those holes are for the spare wheel mount that broke and just lay there. Beneath that it's the poor isolation material that crumbling down. I agree it doesn't looks good and need to be fixed.
 
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Another trial, my friends.
Follow Dan's suggest and checked the terminal in the ECU plug.
Of i did it right, on "2000" mode it shows 1200-1900 ohms but immediately dropped to "1" like I'm not touching anything. Every time it blinked a difference reading and dropped to 1.
At "20k" mode it shows 3.26k ohms at stood there.
The car is at rest of course so the coolant temp is around 25C degrees so it spouse to show between 2000-3000 ohms.

But I discovered a probably important issue:
The terminal was a bit corroded! How?
And I guess it's a reason for mis-reading, right?
20201019_192436.jpg


I will give it a clean with contact spray and a fine brush a start the car.
 
81x said:
Another trial, my friends.
Follow Dan's suggest and checked the terminal in the ECU plug.
Of i did it right, on "2000" mode it shows 1200-1900 ohms but immediately dropped to "1" like I'm not touching anything. Every time it blinked a difference reading and dropped to 1.
At "20k" mode it shows 3.26k ohms at stood there.
The car is at rest of course so the coolant temp is around 25C degrees so it spouse to show between 2000-3000 ohms.

But I discovered a probably important issue:
The terminal was a bit corroded! How?
And I guess it's a reason for mis-reading, right?
View attachment 37647

I will give it a clean with contact spray and a fine brush a start the car.
Click to expand...
Over the years folks have reported occasional issues with "the big plug." It is thought that if one is overly enthusiastic about cleaning their engine bay to the point of hosing it down, or on cars where the rain tray has been removed, or on cars that have spent a LOT of time outdoors, water can wick down from the part of the FI harness at or near the top of the engine, travel down the large bundle of wires and seep into the plug, causing corrosion.

As your car has significant chassis corrosion in the spare tire compartment area where the FI controller lives, it's not a total shock that the big plug is showing some green fuzz. The wiring to the FI CTS is the wire from the corroded connector to one pin on the CTS, across the CTS and then to ground, which for this particular circuit is one of the two (can't recall which ATM) grounds that attach to cam box cover. If your leads are long enough you can check resistance of each segment of the circuit.
Segment 1: from that corroded contact to one of the two pins in the FI CTS connector plug.​
Segment 2: from the "other" pin of the FI CTS connector plug to the correct one of the two grounds on the cam box cover.​

There may be a reference to tell you which pin is which on the FI CTS connector plug, but I do not have that info handy. But it's not hard to figure it out with the multimeter.

Looking at the pix you posted of the yellow plug (with FIAT molded in the plastic) at the FI CTS, I noticed something. My car is an '86 so there might have been production differences comparing very early FI cars to later cars, but on my car all of the plastic plug housings are black, and all of the wiring inside of the FI harness is white. Compared to your car where the plug is yellow and the plug's wires seem to be conventional CAVIS (the company that made a lot of Bertone's wiring harnesses) colored and striped wires. Could be that's how it came from the factory, or could be that the plug was replaced and if your wiring resistance checks uncover a problem, the problem could be how that "foreign" plug was grafted into the original harness.
 
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81x said:
Another trial, my friends.
Follow Dan's suggest and checked the terminal in the ECU plug.
Of i did it right, on "2000" mode it shows 1200-1900 ohms but immediately dropped to "1" like I'm not touching anything. Every time it blinked a difference reading and dropped to 1.
At "20k" mode it shows 3.26k ohms at stood there.
The car is at rest of course so the coolant temp is around 25C degrees so it spouse to show between 2000-3000 ohms.

But I discovered a probably important issue:
The terminal was a bit corroded! How?
And I guess it's a reason for mis-reading, right?
View attachment 37647

I will give it a clean with contact spray and a fine brush a start the car.
Click to expand...

Be very careful with any abrasive (brush) when cleaning these, the coating is likely already compromised, and brushing it will only make it worse. Contact cleaner & a folded dollar bill is about as abrasive as you want to get. Terminals can be replaced without too much headache, however you do need good electrical crimping pliers and the replacement terminal(s) - the newer ones have a spring tensioner around the prongs, and 2 wider prong vs. 4 smaller.
 
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@Dan Sarandrea (Phila) you could be right about the corrosion, I just wonder why that terminal is the only one to be corroded? Weird.
Could it's wire be faulty as well?
For the sensor plug, my guess that it is not original, it looks like someone mess with is and covered it with isolation tape, the rubber boot is gone also.
The ground from the sensor to the body works good, I will try your other suggestions. Thanks!

@lookforjoe thanks for the warning, I thought of cleaning with a toothbrush but I'll go easier at first.
Are those replacing terminals generic or something particular?
 
81x said:
@Dan Sarandrea (Phila) you could be right about the corrosion, I just wonder why that terminal is the only one to be corroded? Weird.
Could it's wire be faulty as well?
For the sensor plug, my guess that it is not original, it looks like someone mess with is and covered it with isolation tape, the rubber boot is gone also.
The ground from the sensor to the body works good, I will try your other suggestions. Thanks!

@lookforjoe thanks for the warning, I thought of cleaning with a toothbrush but I'll go easier at first.
Are those replacing terminals generic or something particular?
Click to expand...

Bosch used them for many EFI systems -TE technology - Junior power timer grabbed the first listing I saw, search around for smaller quantities. I'd change the two at the sensor also, and replace the housing if its questionable.

www.ebay.com

30 x 2.8mm Junior Power Timer Female Terminal Pins for 0.5-1.0mm2 sealed wire | eBay

It is forsale High Quality 30(nos) x 2.8mm JPT Female. This is forsale 30 nos. of flat female connectors only. Can made for Vag Repair Sealed wire 000 979 021E or 000 979 133E. It is fit for cramping to FLRY-B Cable with 0.5-1.0mm2 by DIY.
www.ebay.com
 
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81x said:
@Dan Sarandrea (Phila)
The ground from the sensor to the body works good, I will try your other suggestions. Thanks!
Click to expand...

The ground for the FI CTS should be one of the two that terminate onto cam box cover studs and nuts, not to the body. As long as where it's grounded is a good ground that's what counts, but if you're looking to "de-molest" an FI system that seems to have been previously molested, you might as well put it back to original.
 
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I would recommend using CAIG DeoxIT to clean the corroded connector. Works great for cleaning up corroded conductors.
 
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Happy to update that it seems to be sorted.
Replaced the CTS with a used one from my mechanic, all the symptoms are gone.
I will make an order of a new sensor plus other items that were mentioned in this thread, just to be safe.

Thank you all for your help and suggestions, learned a lot.
 
Hi 81x,

I am glad to hear that your problem seems to be solved. So installing a used CTS solved your problem? That is great news and I am sure that you will find that the Bosch L-Jetronic fuel injection system is very reliable and works very well most of the time. When there is a problem like you happened to have it is very easy to fix unlike the over complicated systems in todays cars. I wish we could have "frozen the development" of cars at this point with the Bosch L-Jetronic fuel injection system as it seems to me to be the ultimate blend of simplicity and complexity that results in a very reliable running engine.

George
 
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Hi George,
You're right, as I'm getting deeper into the system, it is quite simple. In my previous classics, I used to a simpler mechanics, this is my first fuel injected classic.
In opposite to my modern daily cars, when you just plug it to a scanner to see what's wrong, here you need to trial and error and actually know to figure out the symptoms.
It may took a while (TBH, these days are taking my breath away, between work and kids at home), but with your guidance I could go step by step and even if some part that suggested here was actually good, now i have the knowledge for next time.

Itay.
 
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