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Discussion Starter #1 (Edited)
Ok, so Ive had my 86 for about 2 years. I got it off of BAT. 1986 Alfa Romeo Spider Graduate

I love the car and have not had any real problems other than intermittent stalling when fuel was below half (full tank cleared issue).
Its been tucked in the garage for a few months and was started regularly until about 2 months ago. Tried to take it out today and it would not start. Cranked but it seems that the characteristic pump hum wasn't there (fuel is above half). The relay clicked but no hum. Its been on a battery tender and voltage is good. The fuse is good. I'll be doing the jumper test tomorrow to confirm power to the pump. I've ordered both drive and main relays to get a head start on shipping. The previous owner had replaced the "low pressure and high pressure fuel pump", (indicated on invoice) but i wonder if the tank pump was replaced ever. I've spent the night combing the boards and think that due to its semi-flawless performance over the last few years that it could be the relays or the pump. I have not got too down and dirty yet on testing voltage, but will once the new relays don't fix the issue. The current installed relays are original. The previous owner was nice enough to include the complete shop manual at least. I'll take any and all advice! Spring has hit NJ (along with Covid) and I just would like to drive around by my self when this blows over!

thanks again
 

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Rather than throw many new parts at it I think it best to make a diagnosis first. Since common things happen commonly, start with the usual Alfa no-start woes. This may not solve the problem but it is good preventative maintenance.
1) clean & secure the battery connections and the ground cable's connection to the body (sort of behind the battery - out of sight/out of mind)
2) Check all the fuses (your '86 Spider should have the more reliable blade type
2a) check the fuel pump fuse. This is located under the shelf behind the seats - near the FI computer.
3) check carefully for any loose/split air ducts hoses and vacuum hoses
4) Check system voltage. A fully charged battery should show 12.6V with everything off. 12.3V is half charged.
4a) Check system voltage during cranking. The computers require about 10.5V to power up and send the make spark/squirt fuel signals. It can sound like it is cranking over fine but if the starter is drawing too much power or the battery is tired available voltage can drop below that threshold. Do these voltage checks at the battery - a dash gauge is not wired properly for these tests.
5) clean the electrical connections at the fuel pump (the main pump is under the car forwards of the right rear axle).
5a) measure voltage at the main fuel pump. It should be very close to the system voltage measured above.
6) your description of stalling when the fuel level is below 1/2 is likely due to either a failed in-tank pump or a faulty stepped hose that connects the in-tank pump to the outlet pipe (inside the tank). Either condition will cause the main pump to struggle possibly leading to its early demise.
7) test for spark. Connect a spare spark plug to one of the spark plug wires. Ground the threaded section and have your trusted assistant turn the key to start so you can watch the spark while the engine is cranking. It should be a snappy blue spark. No spark = no signal to the drive relay = no fuel pump power.
8) post some photos of your Spider - we like photos and knowing all the details (like what color it is...) will help us solve the puzzle.

P.S. see my signature for a page of info about the L-jetronic system in our cars.
 

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Another helpful tool for many of the forum members would be a video of it trying to start. Just a suggestion though.
 

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Its not uncommon for the intake pump not to work since the wire to the pump travels completely around the car passing through 4 or so connectors before getting to the pump.

You should here the main pump hum for a second when you turn the key on.

The qickest way to see if you have a main pump problem is to get a helper. Put the car in natural. Set the parking brake. Then slide your arm under the rear of the car until you can grab the main pump. Have the helper start the car. The pump is either going to run, do nothing or you will feel a thunk.

If it runs you have a problem else wear.

If it doesn't run either the pump died or has a problem with getting power to it.

Last if it thunks. Then trash has gotten into the pump and locked it up. New pump time.
 

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Ok, so Ive had my 86 for about 2 years. I got it off of BAT. 1986 Alfa Romeo Spider Graduate
The previous owner had replaced the "low pressure and high pressure fuel pump", (indicated on invoice) but i wonder if the tank pump was replaced ever.
looks like a nice rust free car from the photos.
the 'low pressure pump' is the in tank pump; the 'high pressure' is the main under car pump. If they were replaced recently by a shop then likely these are ok. The car last started 2 months ago, that is not a long time.

determine if you have spark or not, that's the first thing.
If you dont, confirm cranking voltage is near 11V and if it is, then check crank sensors as per the L-jet spider diagnosis.

If you do have spark, then it'll be fuel supply (after a period of cranking the spark plugs should be wet)
Fuel could be anything from relay, pumps, fuse, fuel pressure regulator, injectors
If it's still winter where you are, check cold start injector is spraying.

As you mentioned, jump the fuel relay (#30 & #87)....if pumps work then, the wiring and fuse etc is good, but relay bad.
 

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Discussion Starter #7
Update,

Pulled the relay and tested power, all is good. Jumped 87 and 30 and pump started humming immediately. A closer look at the relay shows that the 87 terminal looks a little fried. I didn't push it to start all the way. Will it start with the relay pts jumped? See the attached photos.

Any additional input would be great.
1618731
1618732
1618734
 

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Update,

Pulled the relay and tested power, all is good. Jumped 87 and 30 and pump started humming immediately. A closer look at the relay shows that the 87 terminal looks a little fried. I didn't push it to start all the way. Will it start with the relay pts jumped? See the attached photos.

Any additional input would be great. View attachment 1618731 View attachment 1618732 View attachment 1618734
It should do.
That is the nice original Bosch relay, expensive and hard to find.
The new one you ordered won’t be that. It’ll be some KAE relay that is a crap shoot
Still let’s hope for the best?
 

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it should start & run with the relay bypassed with the jumper. But you then lose the safety aspect of a functioning relay. With the relay operating properly, the fuel pumps will be shut off in the event of a stall (as might happen in an accident).

As Dom mentions, some replacement relays are a KAE brand. It physically fits and will power on the fuel pumps but (why is there always a but...?) some have reported that the KAE relay may not cut off the fuel pumps in the event of a stall.
 

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What Jim G said. Check to be sure that both pumps are running. Might be a fuel pressure regulator problem if you find that both pumps are running and sound decent. A sniff on the vacuum line to the fuel pressure regulator may tell the story if you smell gas but not always.
 

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Discussion Starter #11
Update...when I jumped the relay, the in tank pump was the one humming. When I replaced the relay with the KAE, still only the tank pump fired up. I checked the voltage to the main pump and found it was getting power. When the power was applied (with my handy helper) the main pump made a measly groan sound then nothing (could barely hear it unless under the car. Although it is a new pump, i think it is seized. So it looks like the 2yr old main pump is no good. It appears to be a simple job, my question is what pump do you all recommend. I'll start digging on the forum, but wanted to update you on the progress. Do you think that a seized pump would fry the relay?
thanks.
 

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Discussion Starter #12 (Edited)
Update...when I jumped the relay, the in tank pump was the one humming. When I replaced the relay with the KAE, still only the tank pump fired up. I checked the voltage to the main pump and found it was getting power. When the power was applied (with my handy helper) the main pump made a measly groan sound then nothing (could barely hear it unless under the car. Although it is a new pump, i think it is seized. So it looks like the 2yr old main pump is no good. It appears to be a simple job, my question is what pump do you all recommend. I'll start digging on the forum, but wanted to update you on the progress. Do you think that a seized pump would fry the relay?
thanks.
So...
1-I've verified spark
2-inspected all hoses and intake hoses
3-verified movement on the airflow sensor
4-verified voltage at the battery and on crank
5-tried the new and old drive relay
6 -applied power to main pump and tried to start (no luck)

Unless the sound the main pump makes is bad, I'm on to testing crank sensor and injectors. Is the attached video and audio the sound of a seized pump or a functioning pump?

When I applied direct power to the pump it seems to be doing something.
 

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That sounds a bit loud to me. Almost sounds like a pump that's starved of fuel. One way to check that the pumps are pumping is disconnect the fuel line where it enters the main pump. Have someone briefly jump the main relay, and while under the car using a container to catch the fuel, see if the in-tank pump is moving fuel. Reconnect, then disconnect the line between the main pump and filter. Jump the relay again briefly. Then do the same on the other side of the filter. If at any point the flow is not strong, there's an issue upstream. I haven't read every post in this thread, so I apologize if this is redundant!
 

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if you have spark, I'd say the crank sensors are ok.

sounds like the pump is doing something, it's not frozen, but I am not sure the noise is correct either...some aftermarket pumps are noisy, mine is fairly quiet.

to be doubly sure the pump is delivering and hoses are free, pull off the hose at the injector rail, then crank shortly (or jumper) and see if fuel pumps out at a healthy rate (rags etc at the ready)...that checks fuel delivery all along the route to the injector rail.

If you have fuel delivery at the rail, then next check is Fuel Pressure Regulator

Have you checked the small vacuum hose on top of the FPR for signs of fuel (or a frayed/split hose)? If it has fuel in it, the unit is bad.
Pull out a spark plug. Is it wet?
 

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Ideally you would use a pressure gauge to see if the main pump is supplying fuel at the correct pressure. The Fuel Pressure Regulator will regulate the pressure in the fuel rail only if the pump is delivering fuel at the appropriate pressure. If it is too low the regulator can't increase it. And if it's too high the regulator will be overwhelmed causing the fuel injectors to squirt too much fuel.

If you find that the fuel pump & regulator are operating correctly and you have spark but it still won't start you should clean or replace the spark plugs. Repeated failed attempts at starting can foul the spark plugs making further starting attempts futile (and fouling the spark plugs more & more).

1619155


1619156
 

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Discussion Starter #16
Ok cleaning plugs now. I'm no expert but they look fouled. Getting a gauge tomorrow. See pic and video of car cranking.


1619167
 

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Discussion Starter #18
Very fouled!
New plugs tomorrow.

Would those plugs cause a complete no start like the video out of the blue? I have to pull the fuel line tomorrow after new plugs to see what's going on. This is fun but frustrating!

Also, these plugs are 2 yrs old!!
 

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that pump noise would send me crazy! You shouldn't hear anything from inside the car, except maybe a soothing hum when the car is idling.

Did it always make that maddening noise?....sounds like an irish banshee on the rampage;)

Now, I am not so certain you (still) have spark........the tacho needle should jump if you have spark (Tacho is run off the coil)
Check that again, just so you don't run round in circles chasing fuel when in fact it is a no spark situation.
Just plug one 'cleaned up' spark plug back onto one of the leads and crank the engine...you are looking for a crisp, sharp spark.

Those plugs (badly carbon fouled) do look wet, which means fuel (of sorts) is getting into the cylinders.
your piston crowns will be equally wet, I'll bet.
With plugs out, crank the starter a few times, then leave the (new, or properly cleaned up) plugs out a while to allow things to dry out a bit.
 
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