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Discussion Starter #1
I was doing a bit of top down driving the other day and after about sixty smiles of country roads I pulled into a pub for a cold one. I left the pub fifteen minutes later, started up the spider and three or four blocks later I was unable to rev the engine above 2500 before it would stumble and miss.
I was able to get her home and now I need to figure out what happened.
Here’s the details.
1978 Spider with SPICA.
New rotor,cap, capacitor, points, plug wires (only a couple hundred miles on ‘em)
Was easy to start without pressing on the pedal.
Now hard to start, will idle once warmed up but now idles at ~1.1K instead of the old 800
Now only goes up to 2.5K before I get major missing and backfiring from the intake ports.
I am going to replace all the fuel filters this afternoon and check the points / dizzy for anything that may have changed or moved.
Does any of this sound familiar to anybody?
Anything else I should check?
Thanks for any help and suggestions.
Jim
 

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Have you checked if the screws to the rotor are secured tight? I would check that out first since that was recently replaced and not hard to get to.

Andre
 

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I have only one thing to say: Alfa Romeo put a bug into our cars to make all of our cars behave this way to increase dealership returns to buy the 8C!!!! I'm seeing a lot of problems being reported about the same problem I currently have! Tomorrow I'm dismantling the distributor to find out for sure what is going on in there and will report back, but it seems, me, you and many out there are having chaos with our ignition systems.
 

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I have had what sounds like the same problem occur just a couple of weeks ago.
I went back to square one and took the new condensors out and put the old ones back in. That cured the problem....until now.
This weekend the same missing and popping on acceleration has returned ! Whats going on???:confused: I'm reading lots of posts these last couple of weeks about the same problem showing up on '78-'79 motors. Strange. I have not had a chance to look at it but I am feeling it is more than an electrical/ignition issue.:(
Keep us posted and I will do the same.
 

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If you go full throttle, does the engine pull well or is the problem only at partial throttle? An engine that runs badly at other than full throttle can be a sign of a broken compensator link spring.

1. Check to see if one of the rod ends has cracked at the threads and has slipped it's threads, thus throwing the geometry of the long and short rods out of delta.

if ok, then . . . .

2. Check that the pump gap is still .019" with the engine hot and long rod connected.

if ok, then . . . .

3. Remove the barometric compensator on the top of the injection pump (three screws) and check that the compensator link spring is not broken. DON'T move the throttle while the BC is out.
 

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One additional possible avenue for this problem might be fuel delivery specific to the SPICA system; fuel filters and/or fuel pump. I strongly recommend when changing the rear filter, removing it in such a manner so that you can invert the filter, tap it strongly with a rubber mallet and see what comes out of the inlet. Many of the fuel tanks have crud that causies reoccuring problems, keep in mind a crudded rear filter will put a strain on the fuel pump, these fuel pumps can go bad but still operate somewhat marginally.
 

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Roger is correct, of course. I'm assuming that your fuel low pressure warning light is working correctly and not indicating a low fuel pressure condition.
 

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Discussion Starter #8
Andre, everything is tight. The first thing I checked was the distributor set up.

John, I checked the rods and the long rods lock nuts weren’t tight, and the rod itself was loose, but still connected. I’d love to check the pump gap, but that means getting the engine up to temp. Something that I’m having trouble with right now as the car doesn’t want to start. The pump gap does look large .25” when cold, but I’ve never adjusted it and I assume it’s always been correct.
I took the Barometric compensator out and the spring looks great, no rust and attached top and bottom. No fuel smell.

Rogerspeed, after I checked the dizzy I changed the oil / filters (I was in the neighborhood so to speak.) and both the rear fuel filter near the diff and the front fuel filter.
Tonight I’ll put in a set of new plugs, check the timing and see if I can get her up to temp in order to check SPICA settings.
The low-pressure light is not working; I cleaned the connections but nothing. Does the sensor ever go bad? If I short the wire to ground should it light up? I recently had the center console out and may have pulled a wire loose.
Thanks to all for your suggestions. I’ll post again after I change plugs and do continuity check on the fuel pressure light.

Jim
78 Alfa Spider
 

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Uargh! Low pressure light not working? No Spica owner should be driving around without an operable low pressure warning light. That is your first indication that you have a supply pump going south on you. Continuing to operate the engine with low fuel pressure can damage the injection pump.

If you ground the wire that attaches to the sensor, the light should come on. If not, you've got a bad bulb or a wiring fault. As a troubleshooting technique, you can use an ordinary test light as a substitute for the dash light. Just connect one end to the pressure switch and the other to a 12v source. When you turn the key switch on, the light should come on for a few seconds while the pump pressurizes the system, then it should go OUT and never come on again until the next time you turn the key switch on.

Use a test light and see what you find out. If the light comes on, then doesn't go out after a few seconds, try kinking the fuel outlet line (connected to the front fuel fitting on the injection pump and see if the light goes out then. If so, you probably have a supply pump going out on you, or a leaky Pressure Relief Valve if you car has the type front fuel filter that has a PRV.

Go to www.wesingram.com/hp.htm and download the Fuel Supply Diagnostics Guide.
 

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Discussion Starter #10
Yes, of course you’re right about my negligence with the low pressure light. I must have done something when I had the center console off.
You can hear the pump running and the fuel returning to the gas tank.
Bad lamp or wire. No light with lead shorted to ground, 12v lamp test shows the sensor working, (on for a second or so then off. ) Thanks for that tip.
It will be the next thing I fix.

As an update-
I put in new plugs and still was unable to make her idle. ( would try, and almost catch, but....)
Tested the coil at a local parts store and replaced it. Still no luck.
If I put a spark plug on top of the engine ( grounded out) I only get a spark once and a while, not a steady, regular spark.
I guess I’ll start from the beginning tomorrow.
Jim
 

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We've checked all the obvious stuff, so yes, it's time to go back and check everything A-Z starting with the ignition. Have you tried using spray starting fluid to start the engine? Also, what do the spark plugs look like? Any possibility that you crossed-up a couple of plug wires??
 

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Discussion Starter #12
I don't think the plug wires were off. It was running great. I haven’t tried starting fluid. Plugs are brand new Golden Lodge 2HL. I’ll check everything else I can think of. The way it came on so suddenly is what bothers me. It was pulling strong and had great power (or is it torque :^) and would rev to red line with no problem. Then like a switch was flipped I couldn’t get it past 2.5K. Yup, I got to start from the beginning…………

On another note...
What is the best way to gain access to the fuel pressure light? I don’t have a radio so maybe I can reach up through there. Would the light housing just pull off or is it a twist off?
Thanks for the help.
Jim
 

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I don't think the plug wires were off. It was running great. I haven’t tried starting fluid. Plugs are brand new Golden Lodge 2HL. I’ll check everything else I can think of. The way it came on so suddenly is what bothers me. It was pulling strong and had great power (or is it torque :^) and would rev to red line with no problem. Then like a switch was flipped I couldn’t get it past 2.5K. Yup, I got to start from the beginning…………

On another note...
What is the best way to gain access to the fuel pressure light? I don’t have a radio so maybe I can reach up through there. Would the light housing just pull off or is it a twist off?
Thanks for the help.
Jim
What year is your spider? Think of starting fluid as a diagnostic tool...
(torque is power, horsepower is work?) Your car, either way, has to have power to work...lol:D
 

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Discussion Starter #14
I went through everything I changed and am still having running issues.
Here’s what I have done:
Checked points .018 gap and contacts are parallel.
Returned new coil and re-installed old coil.
New crimp connectors where needed, all contacts cleaned.
Fuel low pressure light on only for a second, stays off while engine is running.
I was able to start the car and run it up to temp. Misses at idle. Idles at ~500
SPICA Pump gap at .019.
I can rev it up a bit, but not past 2.5K
A timing light on the coil corresponds to the missing.
It’s not just one plug, but two or three plugs at a time that are missing.
(no light, no spark= missing)
So, now I’m thinking maybe the condenser is all wonky. Does that sound about right?
I’ll put a test light on the + side of the coil to see if there is any interruption there like a loose connection in the ignition switch.

New Lodge 2HL, new cap, new rotor, new condenser, new points, new plug wires, new fuel filters, fresh air in tires.

Any and all suggestions greatly appreciated.

Jim
 

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When you put the timing light on each individual plug wire, what do you get? Could be an condensor. Are the point burned? Have you cleaned the plugs? Any carbon tracking in the inside of the distributor cap? Did the timing slip??

Triple check the firing order. 1-3-4-2 and the timing.
 

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Discussion Starter #16
When I put the timing light on an individual wire the light doesn't fire when that plug doesn't fire. That is to say the timing light is a visual indicator of the missing plugs. This happens on all cylinders. Points are new and in new condition. No tracking in the cap. (also new) timing has been checked. Injection timing has been checked, and the firing order has been checked multiple times.
I’m guessing something is not letting the coil build up a charge or not triggering it to fire.

Jim
 

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I'm having exactly the same issues with a 76 Spider. Despite a lot of good advice, I have not figured it out yet. It is an electrical problem, not Spica. The timing light shows intermitent spark to the plugs. I just don't know why. I have replaced everything as you have. I'm going to try another new condenser and a hotter coil.
 

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Discussion Starter #18
Update
Here’s what I did to correct the problem I had with my 78 spider.
I removed the distributor and tightened everything up. I changed the weak advance springs with new ones out of a Delco kit and shimmed the shaft to reduce endplay.
I replaced the condenser with a new one and built a new wire to go between the coil and points. I re-gapped to points from .018 to .014.
I also bypassed the ballast resister on the coil by moving the green and black wire to the + side of the coil.
I then rechecked the static timing and fired it up. After it reached temp I timed it to ‘M’ at 4500 rpm.
It now idles at 750 and revs to redline with ease.
I think the condenser was at fault and the slop in the distributor wasn’t helping any either.

Thanks for all your replies and suggestions.

Jim
 

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On my 74 spider, the connection on the bottom of the distributor corroded.it is a stack of washers and insulators that feed the coil wire to the points. if you have an ohm meter, check the resistance to ground of the coil wire that goes to the points from the distributor with the points closed, should be very low resistance. the other wire on the coil should go to 12 volts for a bosch blue coil or the ballast resistor if the other kind, and have about 12 volts with the points open and 6 volts with them closed.
cliff
 

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just another thought, without a nice bright fat blue spark at the plugs, you wont get much power from the engine. a weak spark cant overcome the resistance of compression in the cylinder. it takes more voltage to jump a spark in high pressure (like when the throttle is open)
cliff
 
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