79 spider 124 starts and idles, press gas pedal stalls - Help

[My79FiatSpider]

Hi
As the subject says, I have a 1979 fiat spider 124 2000
I just inherited it and I'm just a 'shade tree' mechanic so simple/detailed instructions are appreciated

The car starts and idles no problem and will,run thus way all day.
As soon as I press on the throttle, the engine wants to stall, in fact it stalls many times.
If I jiggle the gas peddle just ad it's about to stall, it catches and stays running. It's very frustrating in fact it's very dangerous when I'm in traffic and it's just not fun to drive like this.

Any ideas?
I'm willing to try anything as long as you can explain what I need to do.

Thanks in advance

[SeattleSpider]

A 1979 . . . this should not be a fuel injected car. If it IS, I have had this same problem. Mine would idle just fine at 1,000 rpm. It would continue to run fine until I increased the rpm. When it got to 2,000 rpm, it would cut out and drop back to 1,000 rpm, BUT continue to run fine at that level. I could not figure it out. I took it to a local Fiat mechanic (yes, they still exist in some locations), and they fussed around with it for a few hours. He said it was the connections in the wiring in the fuel injection system. I still do not quite trust it and have not driven it yet this year. What they told me is that if I have any problem in the future, just disconnect the sensor in the front of the engine, right in the center up high (as I recall it connects right into the "T" in the water/cooling system - i.e. some kind of heat sensor?). I know that is a bad description but I do not have an engine, or diagram, in front of me, so I cannot explain it better right now.

Then again, you probably do not have a fuel injected car, so this probably did not help at all. If you do and want a better description, let me know.

[GeorgeT]

The accelerator pump gasket may be shot. When you press to accelerator, the pump squirts a small amount of fuel into the intake to account for the increased airflow from the open throttle plates. Without the added fuel the engine will die as there is too much air for combustion.

[joelittel]

I have a fuel injected ‘80 and am experiencing very similar problems. I too haven’t trusted my car for a few months now and really want to get this sorted.

If nobody objects I’ll post my findings to this conversation with the intention of helping others with the same issue.

My79 some of the later ‘79s were fuel injected from what I’ve read. Which is yours?

+1 on checking the sensor at the coolant T. A bad one causes all sorts of issues.

My79 you said that you just inherited the car. Is there any chance that you have old and gummy fuel blocking any part of your system? If I let my carb’d motorcycle sit too long I really have to work at cleaning out the fuel system before it starts to function properly again. Usually this involves a fuel cleaner and holding the throttle at various rpm levels for long periods of time. I keep it in neutral and let it warm up fully. Then hold the rpms a little higher and let it idle there until it runs smoothly. Then increase the rpms a little more and hold it there until it smooths out again. With the bike it’s really easy to tell when the gunk has cleared because while holding the throttle steady the rpms will climb as the carbs clear out.

I continue this process until I get it running smoothly at an rpm level that is quite high.

[18Fiatsandcounting]

I agree with the comments above that we really do need to know whether this '79 has fuel injection or a carburetor before we can help much further. If the car is carbureted, then it sounds like the idle circuit of the carb is working fine, but the problem lies with the transition to the main jets. The fact that the car "catches" when you jiggle the gas pedal would seem to indicate that the accelerator pump is working, at least somewhat.

If it does have a carburetor, my guess would be a gummed up carburetor as already mentioned, an air leak in the intake, or possibly an incorrect float level (too low). The idle jet could be partially plugged up, providing enough fuel to idle but not enough for the transition from idle to the main jets.

-Bryan

[My79FiatSpider]

Well, I'm far from being any level mechanic but if given, I'm pretty good at following instructions.
I'm fairly certain that this car is a carborated car.
Will the vin number help? Would it help determine if it's carbonated or fuel injected?
Thanks for the help so far. Any other help suggestions are greatly appreciated
Thank you!

[aj81spider]

If it has an air filter in a circular or square housing on the driver's side of the engine it's cabureted.

If it has an air filter on the passenger side snug up against the fender with a rubber air hose going across the top of the engine to a plenum on the driver's side it's fuel injected.

Here's a picture of a fuel injected engine with the hose visible

[joelittel]

Sorry to Request a tangent... but, AJ, tell us about your chassis stiffener.

[aj81spider]

Sorry to derail the thread.

That came with the car when I bought it. The guy I bought it from was very proud of it. However all it did was tie the two floppy fenders together and didn't do anything meaningful to stiffen things up. That's an early picture right after I bought the car. I removed it and tossed it.

[RRoller123]

It didn't attach at the shocks?

[aj81spider]

No - it tied into the lips that the gasket that seals the hood attaches to. Hence it was completely useless.

[tima01864]

I looked at a 2000 a few years ago, He showed me the fuel injected engine and said see a turbo. I had never seen a fuel injected Spider before. No, Not a Turbo jut fuel injected. The previous owner took it off and sold it to Him as a turbo. Probably wasn't a bad car, But the guy he bought it from painted it red with a paint brush. I walked away.