Going for first fire

sounds

good to me.
on the thermostat housing there is a sensor pull the connector make sure it has no corrosion that can make the car not run or if corroded the car will start but the corrosion will keep it from getting a good connection and shut off also on the side of the distributor there is a small black connector check it if it is not connected or is loose it may start but will shut off from the vibration of the engine running.
check all connections on the distributor coil again loose connections car may start but shut off from vibrating .on my car it would start run drive fine until I hammered down on the brakes the car would shut off it was a loose connection on the distributor coil
 
Pump on too early issue,,

This occurred to me many years ago. Didn't know of this site at the time, so I was on my own. I always figure if it's already broke ""nothing to lose"" When I removed the top of the AFM I checked it out and observed how moving the flap worked ,etc. there is a set of points in there and I forget how it goes but as the flap returns to it's rest spot the points should now open or close. I slightly bent the arm to give it contact ? or gap ? I forget which. Someone had made a comment about butchering the unit,, it has worked as supposed to for many years since. This however would not affect your other problem of start and stall though. Your pressure droppong down to 0 could be due to the fuel pressure regulator. Is there one on the car.???? I resealed the AFM with silicone, and it's been fine since.
 
There's a regulator there, no idea if it's doing it's job yet. I'll have to through the system step by step as per the guide. I would think that it should run even if the regulator is failing, there is 35psi of fuel pressure. Maybe I should try to watch the pressure while trying to start?
Hmmmmm.
Here's a movie (not much to look at)
http://homepage.mac.com/jvandyke/startfail.mov

I'm not sure if my initial hookup was poor (probably). But I redid the pressure gauge assembly with some teflon tape and it tells me pressure goes to 35 and STAYS up, it was slowly falling but very very slowly. I think it's one of the sensors or the EC telling the system to shut down. I'll have to start the ohms tests I think.

Guide says to check for voltage at the injectors (says to use a light but won't a multi meter work too) I'm a bit leary of pulling too hard on those connections do they just pop off or is there a release?
 
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Regulator is not your problem...

jvandyke said:
There's a regulator there, no idea if it's doing it's job yet. I'll have to through the system step by step as per the guide. I would think that it should run even if the regulator is failing, there is 35psi of fuel pressure. Maybe I should try to watch the pressure while trying to start?
Hmmmmm.
Here's a movie (not much to look at)
http://homepage.mac.com/jvandyke/startfail.mov

I'm not sure if my initial hookup was poor (probably). But I redid the pressure gauge assembly with some teflon tape and it tells me pressure goes to 35 and STAYS up, it was slowly falling but very very slowly. I think it's one of the sensors or the EC telling the system to shut down. I'll have to start the ohms tests I think.

Guide says to check for voltage at the injectors (says to use a light but won't a multi meter work too) I'm a bit leary of pulling too hard on those connections do they just pop off or is there a release?
Click to expand...

If your injectors are seeing pressure, then a regulator should not keep it from running. It may make the mixture rich or lean, but it should continue to run after initial cranking.

The fuel pressure "leaking down" is due to a faulty check valve, or possibly leaky injectors. It probably does not have anything to do with anything electronic.

I'm still leaning towards the AFM being faulty. This would also explain the fuel pump running when the doggie door is not open.

The injector trigger wires are held to the injectors with a small wire clamp that runs the perimiter of the rectangular "terminal" at the end of the wire. The wire clamp is C-shaped, and if you use a small pick to pull the wire away from both sides of the terminal, it will slide right off. If you yank on them too hard without releasing the wire, it will probably break the plastic in the housing. Don't do that. :)

Pete
 
Post some photos

I think the obvious things have been covered, so going through the FI troubleshooting guide step by step would be the most productive approach. In the meantime, perhaps you can post some close-ups of a few areas:

  1. The coil and related electrical connections.
  2. The distributor and related electrical connections
  3. The dual relay (located in the spare tire well) and connections.

Someone here might just be able to spot the problem.
 
Pictures are here.
http://gallery.me.com/jvandyke#100348
I'll put one below too.
Many thanks. I think we're making progress. Maybe I can borrow an AFS from a local Fiat guy to check, seems an easy part to swap out.
I don't see that big red wire in the diagram.....hmmmm

relays.jpg
 
I think the AFS (is it sensor or meter?) is bad, it "seems" to fail the test at the relays. Please tell I won't have to buy one for $500. Ugh.
 
Fat, red wire?

The fat red wire going from the white connector on the dual relay and down to the right is the main power supply for the FI system.
 
Thank the Maker. $80 I can handle. $500 would have been the kiss of death. I will rework the tests to try and be SURE first though.
 
Jim Young said:
This however would not affect your other problem of start and stall though.... I resealed the AFM with silicone, and it's been fine since.
Click to expand...

A faulty AFM(S) wouldn't do a start and stall? It's in the "starts and stops" section of the guide I'm using. I'm pretty sure it fails the test. Probing the proper terminal on the relay, going to ground and turning on the key should produce voltage (or light the light as the guide tells me to use a test light but I'm using a meter). I get nada.
Using this http://www.angelfire.com/wa2/fits/fits/fi17-18.jpg
I have nothing despite my lovely assistant opening and closing the flap.
It tells me to check wires as in diagram 19 but I don't know what diagram they are referring to.

Above I said no voltage but that was wrong, as I knew it must be since the Fuel pump was running, I got a better ground with my tester and everything changed.....Still fails test #25....
 
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It seems you did test #24 and got no voltage. You could also do the same with terminal 88z, it should be hot at all times and measuring this will verify that your meter is properly grounded.

Did you do test #25? I think the diagram referred to is this one.

Failing test 24 and 25 is a strong indication that the switch in he AFM is not working. You can measure the switch directly by measuring the resistance between terminals 36 and 39 on the AFM as you move the flap. You should see close to 0 ohms with the flap open, close to infinite resistance with the flap closed.
 
Yes, I tried both those. I want to try again though as it is hard to verify the probe is making contact and the ground is decent. I'm also going to to the Ohm test at the ECU connector. I suppose it could be the ECU too?
 
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J... good conversations here...

... and you are indeed making progress.

It is very evident though you have several intermittent and/or dirt connections.

Walking through the FI guide like you are doing allows you to actually SEE what is failing. Using a VOM is actually BETTER than a test light, btw...

Continued success... this is gonna be GREAT when you finally discover the cause!
 
One guide I'm looking at tells me to check resistance on the pins on the ECU connector, 6,7,8
Says no more than 600 OHMS at 6 and 8
No more than 1200 OHMS at 7 and 8
No more than 600 OHMS at 9 and 8.
I have 390 at 6 and 8
305 at 7 and 8
213 at 8 and 9
Does this mean it passes? All are well under the maximums.
I'm really very electrically challenged.
Somewhere I read to check resistance at the pins at the AFM itself.
Then I will redo them all.
I think I found that check for the pins at the AFM connector (I assume it is really the same test as the ECU harness runs to the AFM connector).
I got in spec resistance and I did get a change in resistance between pins when moving door.
BUT
The test from the guide that has you checking voltage at the relay
this one: http://www.angelfire.com/wa2/fits/fits/fi17-18.jpg
Shows failure.
I have a full 12v at test 24, output to fuel pump from fuel pump relay, with the door open or closed (as I know since the pump runs all the time)
And I get no change on test 25, (input to fuel pump relay), that is no voltage with door open or closed. According to the test, if this fails check the wires (not sure what to check besides quality of connections) it then says to replace the AFM.
I guess that's where I'm at.
Off to buy one. I'm pretty sure I covered my bases and am not throwing parts at it willy nilly.
 
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You can measure the switch directly by measuring the resistance between terminals 36 and 39 on the AFM as you move the flap. You should see close to 0 ohms with the flap open, close to infinite resistance with the flap closed.[/quote]

I have zero ohms with door open or closed. I'm thinking I'll cut it open, nothing to loose.
 
We're on to something

So, at the AFM you are measuring 0 Ohms between pins 36 and 39 (on the AFM, not on the connector that plugs into the AFM, right?), which is what you should measure with the flap open. But, test number 25 in the FI guide never shows voltage, which is what you should see if the flap is closed.

Just to be sure, you did the FI guide test with the ignition on, right?

If you listen carefully to the dual relay in the spare wheel well while your lovely assistant turns on and off the ignition, do you hear the relay click?

With the ignition on, is there voltage between ground and terminal 88a of the dual relay? Between ground and terminal 88b? 88e?
 
ng_randolph said:
So, at the AFM you are measuring 0 Ohms between pins 36 and 39 (on the AFM, not on the connector that plugs into the AFM, right?), which is what you should measure with the flap open. But, test number 25 in the FI guide never shows voltage, which is what you should see if the flap is closed.
Click to expand...
Yes, I get 0 Ohms at 36/39 on the AFM, with the flap closed or open, makes no difference.
I see no voltage doing test #25 (pin 86b of relay with key on, flap closed or open, doesn't show anything either way (BTW direction say you should see voltage when door is open, which I assumed would then go through relay to trigger the other relay to send voltage to fuel pump, so I don't understand why the pump still runs despite no voltage from ASM, but maybe it works backward, I just went by the book..)

ng_randolph said:
Just to be sure, you did the FI guide test with the ignition on, right?
Click to expand...
Yes

ng_randolph said:
If you listen carefully to the dual relay in the spare wheel well while your lovely assistant turns on and off the ignition, do you hear the relay click?
Click to expand...

Yes (but I had to do it solo, assistants are all scarce again, ingrates..)

ng_randolph said:
With the ignition on, is there voltage between ground and terminal 88a of the dual relay? Between ground and terminal 88b? 88e?
Click to expand...
Yes on all counts.
Not sure what that tells me, maybe it tells you something. I hope it's the ASM at this point because I sent for one already.

I'm getting ready to to do surgery on it. Any part that fails gets an autopsy around here.
 
Quote:Originally Posted by ng_randolph
With the ignition on, is there voltage between ground and terminal 88a of the dual relay? Between ground and terminal 88b? 88e?

Yes on all counts.
Not sure what that tells me, maybe it tells you something. I hope it's the AFM at this point because I sent for one already.
Click to expand...

The dual relay contains two relays (duh...) The coil of the first relay is connected on one side to supply voltage through the ignition switch and on the other side to the ECU. So the relay should turn on if the ignition is on and the ECU decides to ground its connection to the coil. This is what you verified by listening to the click and confirmed by measuring the voltages. So we know that the ECU works on this count, and we know that at least half of the dual relay works.

We have also confirmed that the flap switch in the AFM is not working. Here is my guess as to what happened: The AFM failed, causing the engine to not run. The PO found that the fuel pump was not running (it wouldn't, since the AFM was bad) and replaced it. Still no good. He found that the pump was not getting power, and did some wiring change to make it run (which it now does whenever the ignition is on). However, the ECU still does not "see" that the engine is running. This is where I am going from "speculating" to "guessing": If the ECU does not see a "I'm running" signal from the AFM, it refuses to turn on the injectors.

Here is what I would try (and don't tell anyone I suggested this): Make sure the ignition is off and disconnect the battery negative terminal. Then use a paper clip or a piece of wire and short pins 86b and 88b of the dual relay together. This is with the relay installed, and poking the wire / paper clip in from the back of the connector. Then reconnect the battery negative and try to start the car.

What this does is tell the ECU that the engine is sucking in air (the AFM should tell it this, but it's not working) and also keep the auxiliary air regulator energized (right now it does not get energized unless the wiring mod the PO did to the fuel pump also energizes the AAR).

If this works, what you can do while waiting for the AFM to arrive is to try to track down what wiring mods the PO did to the fuel pump circuit.
 
Fascinating. The fuse panel was down when I inspected/bought the car so it's possible the DPO did something on that end. As it is I see only the green/blk wire to the fuel pump + hooked up as it should be and running from the relay. I'm not sure what he could have done at the fuse panel. Any suggestions on what to look for appreciated. A known good (though used) AFM should arrive at my "old foriegn sports car/motorcycle emporium" by week's end. Hopefully I will be one step closer X bliss then. Man, what I've learned over the past week, wow.
I will likely try your jumper idea although prudence says "wait". Prudence is a prude and ain't no fun.

I'm still planning on taking my old AFM apart because I want to see it's guts.
 
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