81 fiat spyder 2000 starts/stalls

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ptmassa

81 fiat spyder 2000 starts/stalls

Post by ptmassa »

81 spyder engine cranks, starts but never really does anything other than cough than stalls. fuel pump is good, fuel pressure is good. Fuel injectors are operating. any suggestions? This is my first fiat. I have spent the last 3 years doing the body work, and now it is time to get it running. Car has not run in at least 5 years.
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red107
Posts: 323
Joined: Tue Apr 25, 2006 7:40 pm
Your car is a: 1981 Fiat Spider
Location: Fleming Island Florida
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Re: 81 fiat spyder 2000 starts/stalls

Post by red107 »

check Air flow meter including the plug to it. sometimes they get corroded.
1981 Fiat Spider 2000
2015 Ram Eco Diesel 4X4 Laramie
2018 Jeep Wrangler JLU
ptmassa

Re: 81 fiat spyder 2000 starts/stalls

Post by ptmassa »

red107 wrote:check Air flow meter including the plug to it. sometimes they get corroded.

point me in the direction of the AFM?
narfire
Posts: 3959
Joined: Sat Dec 27, 2008 2:14 am
Your car is a: 1980 124 spider
Location: Naramata B.C.

Re: 81 fiat spyder 2000 starts/stalls

Post by narfire »

Spark plugs good to go? plug leads good?
AFM is at the other end of the black plastic intake on top of the engine, has a black square box on top. As you crank the air starts to flow and a flap inside starts to move. This will send a signal to the fuel pump to start. Some spark and bob's your uncle, if the timing is set right.
Have you changed the fuel filter. Sitting for a while ,perhaps there is some rust in the tank and this has got to the filter,cheap/easy to change.
The black intake hose should not have any cracks in it and all fittings should be tight.
Just a few thoughts... good luck
80 FI spider
72 work in progress
2017 Golf R ( APR Stg. 1)
2018 F350 crew long box
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: 81 fiat spyder 2000 starts/stalls

Post by zachmac »

Read all of the below, do everything the articles describe and then come back and tell us where you are.

http://bama.ua.edu/~darren/boschindex.html

http://www.hiperformancestore.com/Ljetronic.htm

http://www.fiatspider.com/f08/viewtopic.php?f=6&t=9540

http://www.fiatspider.com/f08/viewtopic.php?f=6&t=9597

No, really, read all of this and do what it says. If your cars still doesn't run we'll go from there.
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
ptmassa

Re: 81 fiat spyder 2000 starts/stalls

Post by ptmassa »

zachmac wrote:Read all of the below, do everything the articles describe and then come back and tell us where you are.

http://bama.ua.edu/~darren/boschindex.html

http://www.hiperformancestore.com/Ljetronic.htm

http://www.fiatspider.com/f08/viewtopic.php?f=6&t=9540

http://www.fiatspider.com/f08/viewtopic.php?f=6&t=9597

No, really, read all of this and do what it says. If your cars still doesn't run we'll go from there.
thanks for the links. I will also add that the car cranks forever, not even a hiccup, with the accelarator at 0%. With the throttle depressed and held down at 100% the car will start, I will say run, but never really runs.coughs and stalls.
So Cal Mark

Re: 81 fiat spyder 2000 starts/stalls

Post by So Cal Mark »

if it's been sitting that long, the injectors are most likely all stuck with varnish. You'll need to remove them to clean them
ptmassa

Re: 81 fiat spyder 2000 starts/stalls

Post by ptmassa »

So Cal Mark wrote:if it's been sitting that long, the injectors are most likely all stuck with varnish. You'll need to remove them to clean them

ok, followed all info in the supplied links best I could. AFM is operational. Checked all sensors, ones That I could find anyways. Seems like the are all good. I have power on3 wires at the dual relay, and I have an inkector pulse at the injectors. Removed the intake cover, cold start injector is dumping fuel when cranking. I checked spark at all 4 plugs.
Good spark on each plug. I have what I say is good fuel pressure at the rail as the cold cold start injector is pushing fuel. Not sure if that should be pushing fuel now as it was 92 degrees out when I workd on it today, but fuel here indicates what I would think is good pressure to the 4 injectors as the feed is off the same rail. I removed #1 and #3 plugs, separate times, cranked engine over and see no fuel spray at all in cylinder. I had thought the plugs smelled of fuel when I replaced them, but the new plugs seem very dry. I want to pull the injectors out and check/replace them. Need some down and dirty quick info on how to get them out with as little pain as possible.
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: 81 fiat spyder 2000 starts/stalls

Post by zachmac »

I responded to your injector removal post BUT I wouldn't rush to do that! I suspect you have a failure of the pump to keep running when you stop cranking. Working with a friend have one of you feel / listen to the FP under the car while you crank the engine and then release to run. Does the pump keep running or stop? I bet it is stopping. if that is the case then let us know and we'll walk through all the reasons that might be.

BTW, the dual realy picks up the injectors and THAT path establishes the run electrical path to the pump. It sounds like that first coil / contact set in the realy is not working.
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
ptmassa

Re: 81 fiat spyder 2000 starts/stalls

Post by ptmassa »

zachmac wrote:I responded to your injector removal post BUT I wouldn't rush to do that! I suspect you have a failure of the pump to keep running when you stop cranking. Working with a friend have one of you feel / listen to the FP under the car while you crank the engine and then release to run. Does the pump keep running or stop? I bet it is stopping. if that is the case then let us know and we'll walk through all the reasons that might be.

BTW, the dual realy picks up the injectors and THAT path establishes the run electrical path to the pump. It sounds like that first coil / contact set in the realy is not working.
I removed the relay from its plastic housing. One coil clicks closed with the key on, the second clicks closed as I crank the engine, I assume from what I have read that this is normal operation. I did question the fuel pump, but it does pump. I have gone so far as to jump 12v battery voltage directly to the pump so it runs with the key in the on position, but not cranking. I will reverify the pump runs for a shurt time after cranking. In a previous post I mentioned I had pulled #1 and #3 spark plug and did not see any fuel spray into the cylinder when the engine was cranked. this car has sat for years without starting, I am thinking the injector tips may be varnished heavily and clogged.
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: 81 fiat spyder 2000 starts/stalls

Post by zachmac »

If you still have the covers off the relay then check that that second set of contacts that feed the fuel pump (the second click you here) stay closed when you release the key to run. If YES then I would agree you most likley have clogged injectors. If no, then we trouble shoot that part of the circuit.

What happens is that while cranking you are supplying one source of power to the coil in the relay that closes the contacts that feed the fule pump. When you release the key a DIFFERENT path of power, through the AFM, provides the power to keep the coil in the rleay energized and therby the contacts feeding the fuel pump closed.
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
ptmassa

Re: 81 fiat spyder 2000 starts/stalls

Post by ptmassa »

zachmac wrote:If you still have the covers off the relay then check that that second set of contacts that feed the fuel pump (the second click you here) stay closed when you release the key to run. If YES then I would agree you most likley have clogged injectors. If no, then we trouble shoot that part of the circuit.

What happens is that while cranking you are supplying one source of power to the coil in the relay that closes the contacts that feed the fule pump. When you release the key a DIFFERENT path of power, through the AFM, provides the power to keep the coil in the rleay energized and therby the contacts feeding the fuel pump closed.

The first set of coils do close when the key is turned to the on position. the second set do close when key turned to crank poistion and then open when I release they key back to the on position. The second set does not stay closed, even for a second, when I stop cranking the engine.
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: 81 fiat spyder 2000 starts/stalls

Post by zachmac »

The first set of coils do close when the key is turned to the on position. the second set do close when key turned to crank poistion and then open when I release they key back to the on position. The second set does not stay closed, even for a second, when I stop cranking the engine.[/quote]


This is good news believe it or not, we are narrowing it down! Do not pull your injectors yet, most likley not the problem (althoug they may ALSO be stuck / clogged).

Now we have to figure out why the contacts for the pump aren't staying closed. We can pretty much rule out the relay itself as the coil / contacts work initally. Either the "run" path for FP contact coil is bad or the voltage to it is weak. On my car I had 12v to it BUT, when it was loaded it dropped to about .5v and the coil would drop out. I had a high resistance on the black wire that feeds the fuse box.

BEFORE we proceed, do this if you can. Crank the car and BEFORE you release the key hold the contacts in the relay closed with a clamp (or your fingers) and then let go of the key and see if the car keeps running. That will let us know the injector condition.
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: 81 fiat spyder 2000 starts/stalls

Post by zachmac »

AFM is operational.quote]

What do you mean by this? What checks did you do? The AFM has a pair of contacts that have to close to complete the "run" path to the comination relay coil for the contacts to the fuel pump. If these aren't completing the circuit, the car will start on crank and then stall when the fuel pump relay drops out (like yours is doing). What checks of the AFM did you do?
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
ptmassa

Re: 81 fiat spyder 2000 starts/stalls

Post by ptmassa »

zachmac wrote:AFM is operational.quote]

What do you mean by this? What checks did you do? The AFM has a pair of contacts that have to close to complete the "run" path to the comination relay coil for the contacts to the fuel pump. If these aren't completing the circuit, the car will start on crank and then stall when the fuel pump relay drops out (like yours is doing). What checks of the AFM did you do?

Disregard allllllllllllllllllllllllll previous. I started from scratch. I put everything back to the way it was before I did step one of troubleshooting. I will run through what I found. Can we start from scratch, i have gone in too many directions and need to just double check everything I have done.

Car cranks, coughs and sputters but never starts. Fuel pressure is 42 psi at fuel injectors. All spark plugs, wires, cap rotor replaced new. Spark is good at each plug. No fuel injector spray into any cylinder. I believe it was ZACHMAC who had sent me trouble shootig from wcmotors.com. I started fresh with the 13 page diagnostic guide supplied.
No voltage at fuel injector connector. Per the guide I went to the dual relay next. Connected test light between 88Z and 85 terminals. No light on. I connected 88Z wire to ground and test light came on. Per the guide the next step is to replace the ECU.
Now I am by no means a genius, but 85 wire is a ground. I jumped ground to 85 wire, went back out to the injectors and low and behold there is voltage there now. I returned to the dual relay and completed the terminal checks on 86c,88a,88e,88b using terminal 85 with the modified ground. I then went to the ECU harness. Checked terminal 1 to ground. then checked terminal 1 to 5,16, and 17. Per the guide if the light lights to this point replace the ECU. Same info as I got when I found 85 wire no good.
Being as I know I am not a genius, I realize that the temporary repair of wire 85 is by no means the go ahead and finish the trouble shooting. Pretty cut and dry no circuit between 88z and 85; replace the ECU.

Am I looking for a problem that I will not find without an ECU replacement? Any suggestions other than going back and checking air flow meter, coolant sensors, thermo time switches? I had no voltage at injector harness, I checked 88z to 85, failed the test, is ECU replacement my next step?
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