Alfa Romeo Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
1979 spider veloce. Starts great. Idles great (~600rpm). Step on gas ... stalls. Will restart (sometimes needs a couple extra seconds). I can tap at the gas pedal a couple times and it gets going. At speed runs like a top. Hot, cold, whatever, it always stalls when you step on the gas while idling. No warning lights (and I have seen the fuel pressure light come on for a split second at start up so its working.) Other than new fuel filter, any clues? :confused:
 

·
Registered
Joined
·
4,718 Posts
The fuel pressure light might be the clue you are looking for. I would change out the fuel filters and see if that solves the problem. I would also check the fuel pressure. If it is stalling right off of idle, it might not have enough fuel pressure to feed the pump and the needs of the engine.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #4
Also something to check...Make sure the throttle linkage rods are the proper length .... and have not been tampered with.
This is looking like a winner. For now I bumped up the idle screw at the top. Its idling a little higher (~750rpm) and the stall is pretty much gone. I'm still not real thrilled with how she's reacting to punching the accelerator though. Which I guess means adjusting those throttle linkage rods.

I found this so far:
http://www.alfabb.com/bb/forums/86580-post10.html

I'll kick around in here and read a bit more.
But in any case ... she doesn't stall at stop lights now. :)

BTW, I yanked the fuel filter out and had a look at it. It looks fairly new so I'm going to hang on a bit on replacing it just yet.

Thank You AlfaRomeo1750 and velocedoc for your responses.
 

·
Registered
Joined
·
995 Posts
Thermo actuator's gone. Get a replacement, and a weekend. If it ran OK on a failed one that means the adjustments are all outta whack. It'll take some tinkering to dial it all back in properly.
 

·
Registered
Joined
·
4,718 Posts
You didn't turn one of those two screws on top of the manifold did you? That takes a very special tool to set the factory reference for the throttle stop at both ends. All of the rods are set from this setting. The rear fuel filter might look good but did you back flush it to see if it was packed up with junk from the fuel tank? There is a filter inside of that and it gets the large and small junk from the tank. The very finest junk is trapped by the front fuel filter before it gets inside of the pump. Any sediment going through the pump can damage those pistons as they are measured in very very tight tolerances. The rear filter will pack up and affect the pressure.

Is the O ring inside of the idle air adjuster taken out? This can affect idle. There is another thread running now that talks about this. I took the one out of my wifes spider and the car idles so much better now. I had forgotten about the rubber O ring expanding cutting off the idle air.

What color are your spark plugs? Do you have the required .019" on the long rod?

There are a lot of factors that feed into the idle and how the car runs. The BB is the best source for helping you sort this all out. :)
 

·
Registered
Joined
·
9,977 Posts
This is looking like a winner. For now I bumped up the idle screw at the top. Its idling a little higher (~750rpm) and the stall is pretty much gone. I'm still not real thrilled with how she's reacting to punching the accelerator though. Which I guess means adjusting those throttle linkage rods.

I found this so far:
http://www.alfabb.com/bb/forums/86580-post10.html

I'll kick around in here and read a bit more.
But in any case ... she doesn't stall at stop lights now. :)

BTW, I yanked the fuel filter out and had a look at it. It looks fairly new so I'm going to hang on a bit on replacing it just yet.

Thank You AlfaRomeo1750 and velocedoc for your responses.
That screw on the top of the manifold is not intended to adjust the idle speed. That screw is set with a factory jig to set the correct geometrical delta between the short and long rods.

Since the fuel low pressure warning light appears to be working correctly and indicating normal, the next step is to make sure that the ignition system is correct and timed to spec. After that, I would first check that the Thermostatic Actuator is working to spec. Also, did anyone change the timing of the injection pump??

If everything checks out normal, then I'd recommend that you do a complete soup-to-nuts tune of the fuel injection system. The system must be tuned in lock-step order and NOT "fiddled" with until it runs. You'd be amazed at how out-a-wack the system can be and still actually run, albeit nowhere near like it should. Tuning the Spica system isn't that hard, but you do have to actually read the instructions and follow them to the letter.

If you want the tuneup instructions and other Spice tech material, send me a PM with an email address.
 

·
Registered
Joined
·
995 Posts
And that's the worst part... once you do get a proper thermo actuator (TA) and screw it in, a car that kinda-sorta almost worked properly just won't work at all because everything's been set so out of whack. IME, it takes one full day of tinkering, followed by several "spend an hour on it" weekends before it's right again.

Now, once it's right, it's amazing. Starts up like it's full of the latest electronics when it's -10F outside, never idles fast, never coughs, never sputters, no matter what. Even my modern cars don't run quite as well as my spider does when it's bang-on tuned.

Of course, then the TA decays a bit, which throws everything out of whack, and you have to do the last 1/3rd of the tune procedure on it to get it back. But hey, if you wanted a car that didn't need to be fiddled with, you'd've bought a Honda, eh?
 

·
Registered
Joined
·
4,718 Posts
The next question is...what can we do to help you?

Did the car run normal and this suddenly start happening?

Are your plugs black? That would be an easy indicator that the thermostatic actuator is defunct. A replacement is about $230 and you turn in your old core. The other way to check is to remove the bottom from the injection pump when it is cold and feel the bottom to see if the plunger is sticking out. If it is flush with the end, you will have to get a new one. But...even with a dead actuator the car will still run.

I will take a guess that the rods are all out adjustment and the air/fuel set up is out of factory settings.
 

·
Registered
Joined
·
995 Posts
The bottom of the actuator, that is, not the bottom of the pump :).
 

·
Registered
Joined
·
6 Posts
Discussion Starter #11
I just bought this spider about a week ago.
I was driving a 92' volkswagen cabriolet (which is just a really not so good vehicle). It died. Like game-over died.
Was walking past a lot of for-sale-by-owner cars.
Test drove it an bought it same day.
Anyway.
I can see it has new tie rods ... newer anyway.
And who f'ing knows whats some mechanic/idiot-like-me has done to it.
I'll have to slowly walk through stuff.
But for now ... it starts, idles, an moves down the street without any trouble.
And its awesome.
Thanks everyone.
Seriously.
I'll keep at it. ;)
 

·
Registered
Joined
·
4,718 Posts
Good that it runs and you can enjoy it. :D

I can relate to this very well. I bought a beautiful black Alfetta sport sedan from a leasing company in Los Angeles. It was perfect. I made the deal, and a couple of days later when I went to pick the car up, the car ran like cr*p. It would barely get out of its own way. The company said they farmed the car out to a smog shop and got it to pass. Yeah, they did pass it and cleanly. The rods were so far out of adjustment it would barely take the gas. Took me a good half hour to sort out the rods in the parking lot before I jumped on the freeway to get home. I suspect that might be your case if they installed new throttle rod ends.

You didn't say where you are located, as I was wondering where you could take it to get this all sorted out.

BTW...you have a good taste in cars as you did buy an Alfa! :D
 
1 - 12 of 12 Posts
Top