It has begun - 1981 FI Spider

[sstarch1]

Update!

So, it's been a couple of weeks and here is the latest:

Cooling System/Issue has been fixed. The radiator switch wasn't working, poor ground or bad switch, idk; but i installed a new switch which turns on at 165 degrees.

I still have a small coolant leak from the radiator, which i notice everytime i drive, etc, but my new favorite mechanic (Joe in Redwood City) says to just top it off, etc.

Now, for the current issue #1: Stalling during "warm-up" mode.

Here are the symptoms, starting the car up, it idles a little rough (at about 6-900rpm) for 10-30 seconds, and then purrs nicely at about 1,100 RPM. If i put my foot down on the gas pedal (sitting still, or driving), when i remove the gas pedal the car stalls. This happens when driving or sitting still. After a longer amount of time driving, pushing the clutch in/releasing gas pedal results in the car working properly and having an idle around 1,100-1,200.

When the car does stall out, cranking the ignition doesn't get it to fire back up, but cranking the ignition a bit and blipping the throttle does!

So, i've talked with Joe about this, and he showed me, with the hood up and the car already warm, that when he pulls on the throttle cable and releases it, you can hear the faintest squeek from the AFM. He thinks that the AFM isnt closing the whole way, thus letting some small amount of air in. This makes sense to me. As a result, im getting a lean mixture and the engine stalls. When i crank and blip the throttle, more fuel is added and it starts back up. He said that when replacing the air filter, to take the AFM unit off, and lube it a bit to encourage the flap to close the whole way.

Questions:

• Is the AFM, especially given the little squeek, the primary suspect?
  It could be the Aux Air Regulator too?
  Should i adjust the idle speeds to recommended amounts, in hopes that this will fix my whole problem? (i doubt this)
  Is this a good Air Filter to buy as a replacement?
  http://www.fiatplus.com/1980-85-fi-air- ... 79408.html

Thanks much everyone!

[rlux4]

If your AFM is squeeking it needs some lubrication is all. Don't use a petroleum based lube (WD40 or such) as they leave a residue that will trap dirt and dust. This is if the squeek is from the pivot, if it's the flap scraping on the plenum you'll need to do some light sanding.
The AFM won't close all the way with the engine running, the intake of air will be holding it open. It's only closed when the engine isn't running.
The AAR should be closed by the time you're at operationg temp. It and the cold start valve are cold starts only, once it's warm they shouldn't be operating in the equation.
Ron

[sstarch1]

The AAR should be open by the time you're at operationg temp. It and the cold start valve are cold starts only, once it's warm they shouldn't be operating in the equation.
Ron

Can you clarify? My understanding is that the AAR is used during cold start AND warm up mode. Cold start is the.. well, first 5-10 seconds after starting, and warm up mode is what occurs after until operating temp is reached...

My car stalls during those two modes.. and im quite sure the AAR is used during warm up to compensate for the extra fuel put in by the injector during <120/130 degree?

[rlux4]

That is correct, the AAR is closing during warm up and will be fully closed by the time you reach operating temerature. Our temeratures out here in the Mojave desert are in the high 90s so on my car the cold start valve shuts off immediately after starting, the AAR never fully opens.
Excuse me for saying open when I meant closed.
Ron

[sstarch1]

So i diagnosed the AFM problem. The flap was sticking in the 3/4 open and maybe one or two other positions. This was a slight stick, so depending on humidity, shacking on the engine, etc, it would sometime stick and sometimes not.

I took the AFM off and dremmeled that sucker until it was nice and smooth, sprayed a little teflon and put it back in - runs great! Here's a pic of the inside.



But then, another issue. While i was bent over the engine, playing with the idle adjustment on the AFM, i felt like i got a drop or two of liquid sprayed on me, and then i took a look to find this, the number 1 spark plug:



First of all, i have no idea how that liquid got there, and only there, but further, i can no see a nice little line across the underside of my hood where the water pump is sparying a fine mist of coolant.

Looks like my water pump is about to go, which isn't a surprise if you're read my prior posts and seen the pictures of the leak coming from the water pump...

Ugh, now onto another issue. Might have my mechanic replace it along with the timing belt; maybe ill do it myself, but im hesitant to take on this job right now.

S

[RRoller123]

Might be dripping down from a slow leak in the throttle plate heater hose connections. Mine was doing that. Hope that's it, as that is an easy fix!

[rlux4]

Good job diagnosing the problem.
Ron

[divace73]

if you are going to replace your water pump, you might as well get your radiator flushed and fixed...

[jerzyk]

Hi,I 'm new and I am in proces of buying 81' spider

[steve8462]

i have a related question. i'm planning on adding the t-fitting on the heater hoses near the firewall. my question is, can i disconnect the inlet and outlet hose going to the heater core and join them with the "t"? i live in Georgia so i don't really have the need for heat too much in the winter. doing this will make it so i dont have to strip down to a speedo to drive it

[sstarch1]

Steve,

My 81 has the heater hoses cut. In my neck of the woods (SFBay Area) i never need heat, plus the engine and transmission well through the car get plenty hot for some ambient heat if necessary.

Regarding the "t-fitting" - is that for bleeding the coolant system only? If so, there are methods to do so without any modifications or jacking up of the car or anything else.

S

[steve8462]

[quote="sstarch1"]Steve,

Regarding the "t-fitting" - is that for bleeding the coolant system only? If so, there are methods to do so without any modifications or jacking up of the car or anything else.

yes i was going to do it just for the burping of air from the system. i'm not sure if i even have an air problem but i was going to do it while disconnecting the heater hoses. and i found the required "t" fitting at autozone for less than five bucks. if anybody else needs one and cant find it cheap. let me know. i will scoop up as many as i can

[sstarch1]

I posted a separate thread on fixing my water pump, i still need to update it, but for the record im posting it in this thread also:

http://www.fiatspider.com/f08/viewtopic.php?f=3&t=19032

[giuliot60]

Ron or Jimmy, can you post pics of the thermostat hole and other cooling mods. My 81 is cooling well, but i want to flush the coolant out when I do the timing belt/water pump, and don't want to have air issues when I put fresh antifreeze into it.

Thanks!

sstarch1 - Are you doing the timing belt as well since there in the same area and should probably be done if you don't know when it was last replaced?

[rlux4]

Here's mine with the hole;

It shouldn't be any larger than 1/8", you just want air to be able to get through but not so big it allows too much coolant to bypass the closed stat.
You can see the cooling "T" next to the firewall in the heater hoseby the hood latch in this pic'

I can fill my system on level ground with a little massaging of the radiator hoses until it starts to overflow the radiator, cap it and complete the fill through the "T" and not have to burp the system at all. With a good radiator and water pump you shouldn't have cooling problems, even if you were to live in the desert like I do.
Ron