1980 Fuel issues

[RRoller123]

Yes, that would be a major air (vacuum) leak and would cause all sorts of havoc!

Also, check the little one that hides right under the throttle body. Right where the black air hose connects to the throttle, in that area, but low down on the rear side of the throttle body, under the accelerator spring. That one is pretty much hidden and easy to have a disconnect problem with.

[ideashappen]

Hey everyone that chimed in on my issue......
I apologize for being MIA. Between an overloaded work year and sheer frustration of not being able to find the issue I did nothing.
I do sincerely appreciate all who took the time to try and help but I am still in the same place I was last year. I will be pulling the car out in a couple of weeks , providing the 421 feet of snow we received this year in Quebec is melted enough for me to do so. I may very well just bite the bullet and send it to Remo and his Mike in Montreal to find and fix the issue as I really miss driving the car reliably.
If anyone has had any revelations feel free to respond.

Once the issue is resolved I will detail what was done to further the information on this awesome forum site.

[QuebecFiatSpider]

Hey everyone that chimed in on my issue......
I apologize for being MIA. Between an overloaded work year and sheer frustration of not being able to find the issue I did nothing.
I do sincerely appreciate all who took the time to try and help but I am still in the same place I was last year. I will be pulling the car out in a couple of weeks , providing the 421 feet of snow we received this year in Quebec is melted enough for me to do so. I may very well just bite the bullet and send it to Remo and his Mike in Montreal to find and fix the issue as I really miss driving the car reliably.
If anyone has had any revelations feel free to respond.

Once the issue is resolved I will detail what was done to further the information on this awesome forum site.

I would be very interested on knowing how this story finished since I actually have those kinds of AFM problems...

[QuebecFiatSpider]

Ok it seems like this post is not coming to any conclusion... I would have really like to know what was the problem and how it was solved...anyway...

I just want to state that I made some progress analysing my issues (similar symptoms than what was described in this post).

I used my car three (3) times recently and everything went back to normal...The weather outside is now less hot and humid...

I begin to be pretty sure that the problem I was experiencing is all due to a ambient temperature being over 30°C and high % of humidity....

Is there anybody who may know what electrical components can get influenced by a high % of humidity??

Maybe the spark plugs wires...of cap distributor...

[lugbutz]

Hi Y'all

Just read the whole post which is very interesting.... Mostly because I have the exact same problem.... In my troubleshooting
I managed to isolate the problem to the AFS wiring harness.

I did OHM/Continuity checks at the ECU, at AFM Sensors and the TPS. What I found

1. OHM test at the AFS is fine... all contacts show expected OHM and Continuity. - > AFS Is functions as expecteded
2. AFS testing at the ECU - Testing as per L-Jetronic Manual
ECU contacts 6-8 < pass = 600 ohms -> OK
ECU contacts 7-8 <pass = 1200 ohms -> OK
ECU contacts 8-9 < pass = 350 ohms -> FAILED
3. Tested TPS - contacts 2-18 -> 0L -> FAILED


So after this testing I checked out the AFS connector sure enough there is fraying, so I will replace the whole harness.

This doesnt explain whats up with the TPS.... I am suspicious that it is a different problem....

I ordered a new AFS Harness.... Im hoping it will come this week.... But a postal strike up here in the great white north is kill me!

Cheers

[lugbutz]

BTW Current Temp outside is -6 C no Humidity

[gandyrail]

this really sounds like a double relay issue to me; relays can work some times and not work all the time, and wear out.
You are getting fuel but I'm not sure the injectors are firing so that side of the relay could be sticking......
The temp sensor in the tee, a inexpensive part found at all auto stores, check its resistance at the ECU plug - the AMP connector gets loose at this sensor as it is frequently unplugged.
Don't put your meter on the actual ECU connections bad things can happen Put your meter only on the plug connections.
In my experience if temp connection is loose or the sensor is bad the car will die or run poorly.
Also, the TPS should be set; especially if the throttle stop screw was moved. There are contacts inside the tps that can be cleaned. Clean your grounds and ground pods. Check your fuse block.
Make sure this is not a key related issue, check with your meter behind the key.
Check that you have 12V at cold start valve as you crank over engine, will only have V for 3 to 8 seconds, doubt if this is the issue I think you are only running on this injector.
Also my 1981 FI car will run, like crap, for a short time with AFM unplugged... I think it runs only on the pressure already in the fuel system.
>Hows your brake pedal feel? Block off the brake booster hose and see if that makes a difference; maybe your booster went bad and you have a big vac leak thru the booster.
>I just bought a double relay at Rock Auto... I usually get my stuff thru our Fiat vendors but this purchase saved me a couple Hamilton's.
get the FI troubleshooting procedure I think I saw it in this post above follow the procedure it works and is simple to follow.
Eliminate air leaks is a must there is no such thing as being to small to matter.

[lugbutz]

Is there a document around that tells you how to test the relay?

[kimu]

Same issue I have battled for the last 18 months and I finally found the problem. Fuel Pump.

This requires some clarification. The original fuel pump failed - it was stuck and getting hot. I purchased a replacement locally (in Africa) that looked identical in size and shape, installed it. There was fuel delivery but the car just wouldn't run for more than 3 seconds at a time. Swapped out relay, AFM, ECU, tested all the sensors - all checked out within range.

Replaced the fuel pump (this time bought from a reputable Fiat parts supplier) and the car started within milliseconds. Cause of run-for-3-second issue > Low fuel pump pressure > out of spec pump.

[spider2081]

Same issue I have battled for the last 18 months and I finally found the problem.

This is great news> You have been an an enthusiastic Fiat Spider owner for years and deserve a well running car.

I think knowing operating fuel pressure with the Bosch system is very important. I purchased a mechanical fuel pressure gauge from Jegs for $20 a 5/16 barbed brass "T" and flexible fuse hose from a local parts store. Disconnect the existing hose from the cold start valve, insert "T" in the hose use about a foot of hose to make a shallow loop back to the valve. Another short hose to connect the gauge. Whole set up costs less than $30 and takes about 15 min to install and remove. Incorrect fuel pressure doen't have to be the pump or only a single part in our Spiders. Monitoring the pressure sure helps troubleshooting.

[ideashappen]

Hello From the Void

I had almost given up but decided to bite the bullet and change Distributor, and Coil.

It solved the issue immediately.
I swapped them out just before the winter last year and it seemed to chug a bit but I chalked it up to the cold weather and not having run properly for 2 + years.

I pulled off the tarp, charged the battery, sat down in the car , took a deep breath and turned the key. It started on a quarter turn and purrrrrrrrred. I drove it for a good 2 hours and it was bliss.

Now I have one question if it can be answered.

It seems to be running a bit rich. Would the timing be off enough to run rich but still run well?

[QuebecFiatSpider]

Hello From the Void

I had almost given up but decided to bite the bullet and change Distributor, and Coil.

It solved the issue immediately.
I swapped them out just before the winter last year and it seemed to chug a bit but I chalked it up to the cold weather and not having run properly for 2 + years.

I pulled off the tarp, charged the battery, sat down in the car , took a deep breath and turned the key. It started on a quarter turn and purrrrrrrrred. I drove it for a good 2 hours and it was bliss.

Now I have one question if it can be answered.

It seems to be running a bit rich. Would the timing be off enough to run rich but still run well?

Thanks for giving us the end of the story

Since I already have a new distributor in stock, I'll probably put it in place during this summer and see if things gets better...And by the way, do not hesitate to send me an email giving me your personal information...since I live also in the Mtl. area (St-Jean-sur-Richelieu) we may meet up somewhere someday

[RRoller123]

If it is an FI car, the CSI may be leaking fuel into the intake, and the O2 sensor not able to compensate enough to overcome it.

There are a bunch of possibilities for a rich condition on the FI cars. But leaky injectors are pretty common, especially after all these decades.

[ideashappen]

If it is an FI car, the CSI may be leaking fuel into the intake, and the O2 sensor not able to compensate enough to overcome it.

There are a bunch of possibilities for a rich condition on the FI cars. But leaky injectors are pretty common, especially after all these decades.

Thanks for the input......
Is it a simple change? I don't mind replacing parts as long as I get to enjoy driving the car too. Again this year.... car runs great but still seems rich. I'm an old motorhead so the smell of exhaust as I back up doesn't bother me too much but my GF has issues with it. Sometimes , depending on speed and other variables, I can smell it also curling in forward motion.

[ideashappen]

Since I already have a new distributor in stock, I'll probably put it in place during this summer and see if things gets better...And by the way, do not hesitate to send me an email giving me your personal information...since I live also in the Mtl. area (St-Jean-sur-Richelieu) we may meet up somewhere someday

SO? Did it work for you?
I'min Morin Heights about 75-80Km's from St Jean. If ever up here pm me........ We can check out each other's car... lol....