Alfa Romeo Forums banner

1 - 17 of 17 Posts

·
Registered
Joined
·
42 Posts
Discussion Starter #1
Hi folks!

Boy am I glad I found this forum! Well I've wanted a spyder for ages and this summer a barn-find presented itself that was too good to pass up. Hasn't run in three years due to what the PO explained to me as a bad ignition switch. I dug into the wiring, cleaned up a bunch of connections and now I've got the starter working and spark but no power to the fuel pumps. I've tested the actual wires for continuity but where is this inertia switch? Hoping the ECU hasn't gone on permanent vacation. Thanks in advance for any clues.

Cheers,

Michael
 

·
Premium Member
Joined
·
26,912 Posts
Don't think 84 has innertia switch. There is safety switch in air flow meter (AFM) that serves that purpose in later model L-jetronic systems. You can try to engage fuel pump(s) as there are two one submerged in tank and one under car, by accessing flapper in AFM with key on and see if pumps will run. If not you may have either a bad tachimetric relay or main relay located near fuel injection ECU (computer) under carpet area behind passenger seat. Also check fuse under there first.

You can check wiring in trunk to tank pump and under car for 12v with key on and you may have it to tank pump but not esternal pump, then press flapper and see if you now get power at both places if not run a fused wire from 12v source to pump under car and see if it will run if so one of thse relays probably bad.

Once you have fuel pumps running you may find injectors stuck and may have to shock them with a seperate test cable plugged into each injector one at a time. I have had to bring back a few GTV6, Milano and Fiat L-jetronic injectors that way.
 

·
Administrator
Joined
·
16,802 Posts

·
Registered
Joined
·
971 Posts
My 1984 spider DOES have an interia switch. It is located on the firewall on the passenger side, inboard of the windsheild washer tank.
You won't see an actual switch at first..there is a rectangular rubber cover over the switch itself. I don't have a picture handy but can make one if you need.
 

·
Premium Member
Joined
·
26,912 Posts
OK 86 GTV6 does not have the switch as the change over to newer version of L-jetronic on those models did away with it. Don't think 84-85 had it either. Shows you what little I know about the Spiders.

Going back to 164 area now, bye.
 

·
Registered
Joined
·
971 Posts
Not trying to disagree with anyone but....
I know for a fact that my 84 spider has the switch. I've had it out of my car to check it (a few months ago). I see it on the wiring diagram. I don't think my car is unique.

BTW, my 82 spider had the switch as well but it looked different and was easier to see on the firewall (same location).
 

·
Registered
Joined
·
540 Posts
Another vote, my '84 "had" an inertia switch... removed to resolve a no start issue. Mine, also, located against the firewall... black boot/rubber cover...

Good luck and keep us posted.

Ron F.
--------
 

·
Registered
Joined
·
42 Posts
Discussion Starter #11
stuff

Kenny that would be highly appreciated if you could post up an image. The factory workshop manual I picked up leaves just a little to be desired :D
 

·
Registered
Joined
·
42 Posts
Discussion Starter #14
Okay, I spent a quick couple hours on it this eve to start my weekend and I can confirm that I do have an inertia switch and that sucker is just fine in terms of function & continuity. That was the easy bit ;)

The good news is I do have spark and the starter turns the engine over.

Bad news is I have absolutely no lights at all...but that goes to the back of the line until I can get juice to the fuel pump.

There is no power to the fuel pump fuse, no power to either fuel pump period. I believe the hot wire is white.

The main relay by the ecu(s) is suspect being the first link. It clicks immediatley when I turn the key. Is this normal? I have opened it up and look for burned/cracked traces but nothing obvious presented itself.

If the relay is indeed kaputto how hard is it to replace in terms of availibility via your generic NAPA type retailer?

If it's not the relay then I plan to trace the entire fuel pump wiring, do a basic continuity test. At that point if all checks out fine I'll begin to wonder again if it's the ignition switch itself or worse yet; the ECU may be at fault here. Silly question though, is the iggy switch actually tied into the fuel pump circuit or is the fuel pump governed by the ECU alone?

Thanks heaps for the response to date folks!

Cheers,

Michael
 

·
Administrator
Joined
·
16,802 Posts
Do you have shop manual? I have the copies on CD from www.cardisc.com
The shop manual includes a detailed step-by-step trouble shooting section for the ignition/FI computers & no-start conditions.

In addition to the manual you'll need a volt/ohm meter - nothing fancier than that. It's a lot easier to follow the steps in a logical sequence and being able to rule in/rule out problems than trying to puzzle it out yourself (BTDT...)

Anyway, to answer a few of your questions - the main relay should click when the key is switched to 'on'. How is your batttery? The ECU must sense a minimum voltage before it'll wake up and go to work. Even though the battery may crank the engine over OK, if the voltage drops while doing so it may drop below the ECU's threshold. IIRC, the fuel pump doesn't pump unless the AFM (flap type device on top of the air filter) sends a signal that air is flowing. Are the intact ducts in good condition? All hoses intact? Leaks in the intake ducts prevent the AFM from sensing incoming air (thus no signal to the ECU to supply fuel).

The ECU's are quite reliable (as long as you don't 'fry' them with short circuits - also never remove a battery cable while the engine is running). Perhaps the most common problem with the L-jet system are the two flywheel sensors. They tell the ECU how fast the crankshaft is moving and its position (timing). The two sensors are identical but they have to connect to the harness correctly. A black connector should be plugged into the upper sensor and a grey connector into the lower sensor.

They can be tested with an ohm meter. Unplug one from the wire harness and you'll see three small spade connectors. Should measure 800-1200 ohms between the center connector and one of the outer connectors. Try a search for threads about the flywheel sensors - there are plenty here.

Last thought - I'd wonder why you have no lights. Might be a clue there...? Have you cleaned the fuse box? (disconnect the battery first!) Remove all the fuses, use a brass brush (looks like an evil toothbrush) and scrub all the contacts. I'd suggest replacing the fuses even if they look OK. The fuses used in our vintage Alfas (prior to the blade type) can look OK but somehow still cause problems. Do a search on the fuse box for threads about it.

HTH
 

·
Registered
Joined
·
42 Posts
Discussion Starter #17
Thanks Eric!

This weekend I got intimate with my tester and made a few inroads after cleaning various grounds/contact points/fuse holders etc. Fun times!

At least it's a nice small car and really, it's not bad at all :rolleyes:

I've got the fuel pump running now, pressure is there at the rail but my injectors aren't firing (sparkplugs remain bone dry). So obviously more to be done in the wiring dept. as I have yet to find an intake vac. leak.

Ah heck, this will keep me out of trouble for a while!

Cheers,

Michael
 
1 - 17 of 17 Posts
Top