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Discussion Starter · #1 ·
i have an 82 Spider with the L-jetronic. got this as a project for me and my son. replaced both fuel pumps, main and fi relay, new ignition switch and been thru the l-jet diagnotistics already and replaced a few things.

Car cranks, but cannot get a spark.

Coil was wired backwards, but have corrected that already.
from another post, here is what i have checked.

When you turn the key to ON, do you get 12v at:
• the fused side of fuse 7 -YES
• the (+) terminal of the coil -YES
• the fused side of fuse 8 -YES
• ignition ECU connector terminal 10, green/black wire to/from Drive relay terminal 15, via connector G121 -YES
• ignition ECU connector terminal 4, violet wire from igniton switch terminal 50, via connector G121 -NO

teh odd thing is that the fuel pumps run continuously when the key is on, even when not cranking. that shouldnt be happening. bad ECU?

Help?
Thanks Tim
 

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I believe if air flow meter vane is moved off of zero the pumps will run. Might be worth checking to make sure the vane goes to its closed position.
 

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Spider L-jet does not have the switch for the fuel pumps in the AFM (GTV6 does). The fuel pumps are supposed to be controlled by the drive relay (engine running = tachymetric signal from coil to drive relay = power to fuel pumps) There is also a 'start' signal that bypasses the drive relay during cranking (key to 'start' position). It is likely a PO re-wired something to power the fuel pumps with the ignition on - possibly to bypass a faulty drive relay.

What were the results of all the other checks outlined in the Spider L-jet diagnosis page? What is the system voltage during cranking? Connect a voltmeter to the battery and report what it reads with everything off and then what it reads during cranking. It can sound like it is cranking over well but if it reads below ~ 10.5V the computers will not power up to send the make sparks/squirt fuel signals.
 

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For amusement, when the pumps are active w/o the engine running, reach back there and give the cargo shelf above the ECU and relays a hard thump with the palm of your hand.
(or if the shelf is removed, give the drive relay a pop with a screwdriver handle)

If the pumps stop this is indicative of the points in the relay being a bit fried and arcing.
Basically they arc, the point contacts heat up and sorta 'weld' together. Giving things a rattle breaks that 'weld'.

Should that be the case, make sure everydamnthingelse is corrected before installing a replacement drive relay. Unless you want two screwed up instead of just one.
And you will need a replacement as while you can go on beating the cargo shelf for as long as you like to shut them down, you might not be able to do such after an accident. Active pumps + broken fuel lines + uncouncious or disabled passengers = sucky last moments on earth for said passengers.
(I assure you, being burned to death is not pretty nor painless)

Note this is just something to check and fiddle with while doing the other diagnostics.
Burnt contact drive relays aren't really all that common but do occur and have symptoms simular to what you describe in regard to the pumps running.
Of course other things can potentially cause it too, so consider the above just a test step not a full on cure all.
 

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Soon after buying my 87, I noticed my fuel pumps ran continuous when the key was in the on position, however I did have spark and the car would run. After several checks that were recommended by guys on the forum, and some over the phone guidance by papajam, it came down to trying a new fuel pump relay. Fortunately I came across another Spider owner in the area and he had a spare that I tried and it solved my problem. The original relay was an equivalent relay (KAE brand), which in my post, somebody said that manufacturers quality has been known to be troublesome, so I bought a Bosch relay. Interesting was the KAE relay was date stamped 2010, and developed its problem within 1 year. I suppose I was lucky that the relay failed in a position where it allowed the pumps to run continuous vs. not run at all or intermittently.

Here is a link to my post on the issue:
http://www.alfabb.com/bb/forums/spi...el-pumps-runs-constant-when-key-position.html

Hope this helps, and good luck.
 

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Discussion Starter · #6 ·
appears to be bad KAE drive relay-but still no spark

I swapped out the NEW KAE drive relay for what i thought was a bad original Bosch unit, and the fuel pumps now kick on when i turn the key on, but stop after about a second.

All l-jetronics tests have been completed and all passed. however still no spark.

i do have 12v power at the coil, when checking the + side to a KGG. when cranking, the coil - voltage does not change.

i am thinking the ECU is not getting a tachymetric signal?

Coudl my Original Bosch unit still be defective? or does this point more at an ECU swap to test?
Thanks
tim
 

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The coil activates/runs the relay so if no spark you get no drive relay, no drive relay no injectors or pumps.

The quick pump hum when turning key from off to on is normal, expected and a result of the coil field charging and collapsing 1x when power is initially applied. (it tachymetrically activates the drive relay once IOW)

I'm at a bit of a loss right this moment, but perhaps a good going over of the coil wiring yet again might not hurt along with conducting the multimeter test of the coil proper.
 

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Listen to Eric, the lack of voltage is the most common reason for the Bosch spiders to not start. They crank ok but the voltage is not high enough to fire the ignition computer.

Thanks.
 

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I don't want to hijack this thread, but it was very helpful to me. I've had my Spider for a little over a year and didn't think twice about the fuel pump running continuously when the key was in the "on" position.

Reading this, I went to take a look to see if perhaps it was a failed fuel-pump relay. To my dismay, it turns out that the PO had cut the output wire (pink/white) from terminal 87 of the fuel-pump relay (to the inertia switch) and had, in fact, bypassed the fuel-pump relay altogether by splicing a jumper from terminal 86 of the main relay to the main-fuel-pump wire. (He probably thought that the fuel-pump relay or the inertia switch was bad, but there was just a loose connector on the inertia switch.)

I fixed the inertia-switch connector, took out his jumper, and soldered/heatshrunk the cut inertia-switch wire. To my amazement, it now works exactly as designed -- pump activates for an instant at "on" position but shuts off until the key is moved to "start".

Unknowingly, I've been driving all this time without the inertia switch connected. I'm glad that's now hooked up.
 

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The inertia switch (located on the firewall) was considered redundant and Alfa eliminated it around '84 or '85. A functioning drive relay (located under the shelf behind the right seat) was considered adequate for safety as it would cut power if the engine stalled.

The inertia switch can fail at inappropriate times. Sometimes randomly or perhaps from simply driving over a large bump. The resulting engine stall could be dangerous. The inertia switch can be bypassed by connecting the two wires together. (assuming a functioning drive relay for safety's sake...)
 

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The inertia switch (located on the firewall) was considered redundant and Alfa eliminated it around '84 or '85. A functioning drive relay (located under the shelf behind the right seat) was considered adequate for safety as it would cut power if the engine stalled.

The inertia switch can fail at inappropriate times. Sometimes randomly or perhaps from simply driving over a large bump. The resulting engine stall could be dangerous. The inertia switch can be bypassed by connecting the two wires together. (assuming a functioning drive relay for safety's sake...)
Well, the drive (fuel pump) relay was the one that was bypassed (along with the inertia switch) on my '85, so I guess that I had neither the primary or backup protection. All seems to work now, but I'll watch the inertia switch for the failures you mention. Thanks.
 

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Discussion Starter · #13 ·
Thanks to all who have responded so far. the KAE relay was crap, and i swapped in a known good Bosch drive relay, and found that my TPS was not working, both now working, and with key to start, i get both pumps to run, and fuel at plugs. however still no spark. also swapped a Know good ECU (not fi) and still nothing. will try and wire around the Inertia switch tonight. i have already tested coil, and appears to be good, just no spark. help!!?? i know its got to be something simple and stupid.
 

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Thanks to all who have responded so far. the KAE relay was crap, and i swapped in a known good Bosch drive relay, and found that my TPS was not working, both now working, and with key to start, i get both pumps to run, and fuel at plugs. however still no spark. also swapped a Know good ECU (not fi) and still nothing. will try and wire around the Inertia switch tonight. i have already tested coil, and appears to be good, just no spark. help!!?? i know its got to be something simple and stupid.
I wouldn't worry about the inertia switch if the pumps run. The inertia switch kills power to the fuel pumps. It really sounds like you need to verify both flywheel sensors are working.
 

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Even if the flywheel sensors test OK at the wire harness connector, if it still doesn't start/run then I suggest removing the flywheel sensors to check for physical damage. I have seen sensors that tested OK but when removed had some physical damage to the end of the sensor (appeared like a small dent). Replacing the damaged sensor fixed the no-start problem.

There have also been cases where the sensor's bolt had stripped out causing the sensor to be out of position. The threads in the aluminum bellhousing can be stripped by tightening the bolt too much.
 

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Discussion Starter · #16 ·
Thanks. will do tonight. i have replaced the lower one already, but didnt check the upper one. also, i know the plugs are color coded, (grey vs black), BUT interchangeable. which color is for upper, vs lower? thanks, Tim
 

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Black is the upper sensor, gray is the lower.
 

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Discussion Starter · #18 ·
okay, pulled both flywheel sensors and both are fitted correctly, no damage and clean. both also ohm correctly. again, at this time, many of the issues have been corrrected, and fuel pumps now run when cranking, but still no spark from coil. i have tested the following: When you turn the key to ON, do you get 12v at:
• the fused side of fuse 7 -YES
• the (+) terminal of the coil -YES
• the fused side of fuse 8 -YES
• ignition ECU connector terminal 10, green/black wire to/from Drive relay terminal 15, via connector G121 -YES
• ignition ECU connector terminal 4, violet wire from igniton switch terminal 50, via connector G121 -NO

i want to be sure i am checking this last one correctly, so if anyone has any more direction on that one, please let me know. although i am also getting 12v at + side of the coil, how do i test to see if the voltage changes on the neg side?

any other ideas? could one or both the flywheel sensor leads (on the harness side be broken ?) how would i test that?

Thanks for the continual help. i know we are close, but something simple still holding us up.
tim
 

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Discussion Starter · #20 ·
gotit. let me check that. really trying to isolate if the ecu is sending the pulse to teh coil, or if the flwheel sensors are not sending the pulse....?
 
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