USA Fiat 124 Spider 2 liter engine dies - fuel starvation?

Yunko · Post by **Yunko** » July 8th, 2007, 1:51 am

After removing the obstruction from the fuel line it made no difference....same results. Will order new fuel lines and will test again after they are replaced.

SirYun · Post by **SirYun** » July 10th, 2007, 7:40 am

i not fully shure but i seem to remember that a restictor is in place in the return line (but i have seen a larger inline item fitted using clamps).

a friend with a 124 has a very very similar problem.. but he has not managed to fix that either (very puzzled as well).

good luck and please do post the solution.

joost

Post by **Guy Croft** » July 10th, 2007, 7:55 am

Some hints at this time:

If:
1. air is getting to float chamber and into engine in the usual way (no blockage on air filter/intake)
2. exhaust is not crushed
3. idle shutoff valve on carb idle circuit (if fitted on your carb) is not shutting off the supply at low rpm
4. idle jet is not blocked by debris
5. there is actually fuel in the carb when it dies

I don't see that it can be a fuel related problem.

GC

130tc · Post by **130tc** » July 10th, 2007, 11:35 am

What type of ignition system is on this spider ?
I had a similar problem with my 130tc.
car would run fine then just die for no reason at all.
after many hours of testing and cost from auto spaky found faulty rpm sensor in gearbox which shorted when hot. if i left the engine for 45min- 1 hour car would start fine then stop when temp got hot ( normal running 80 deg)

130TC has digiplex ignition
Checking RPM sensor on flywheel on gearbox

Insert the probes of an ohmmeter set to scale of (ohm)x100 between contacts 2 and 3 of the connector.
value should be between 612 and 748 ohm at 20 deg.
if this is not the case replace the sensor.

Hope this is some help.

Yunko · Post by **Yunko** » July 10th, 2007, 2:37 pm

My ignition system is standard points, plugs, condensor, rotor etc. NOT electric. Actually yesterday I replaced all of thoes items and a new Bosch coil. Over the weekend I changed the last rubber fuel hose (return) and the clamp was in a very hard place to gain acces. After a good struggle with it I found after pulling it off, the fuel line must of been broken because there was no flange on the end and the end was jagged. Also, the fuel line was pushed on over the metal line about 6 inches. Come to find out there was a hole in the fuel line where it must of rubbed against the srarter motor and someone did a poor job of fixing it. I attached a new hose and clamped it well, possiably air was gettting in there somehow. Will find out today on my way home if the problem is still there.

Yunko · Post by **Yunko** » July 16th, 2007, 11:36 pm

GC wrote:

Some hints at this time:

If:
1. air is getting to float chamber and into engine in the usual way (no blockage on air filter/intake)
2. exhaust is not crushed
3. idle shutoff valve on carb idle circuit (if fitted on your carb) is not shutting off the supply at low rpm
4. idle jet is not blocked by debris
5. there is actually fuel in the carb when it dies

I don't see that it can be a fuel related problem.

None of the above exist so if not fuel related what is the next step?

The only other thing I have done not fuel related is install a new coil. Even though I bought the carb new could it be a lemon? I sprayed carb cleaner all around the carb and intake manifold and the only time the engine lost RPM is when I sprayed around the electric choke, then again, maybe the sport air filter sucked a little down the carb. I will try the test again a little later this evening and make sure not to get the spray too close to the air filter. Also replaced all metal fuel lines.

mdburchette · Post by **mdburchette** » July 17th, 2007, 12:25 pm

What does your tach do when the car cuts off? If it drops to "0" or fluctuates it's ignition related. The coil is heat and humidity sensitive. You may also want to replace the condensor.

Post by **Guy Croft** » July 17th, 2007, 12:44 pm

John, hi

a good offering from Denise, and we need to move on from fuel system, I really think it's not that;

As I said:

If there is fuel in the carb when the motor stops it cannot have stalled due to fuel delivery per-se. The carb float chamber is vented to atmosphere (or should be, make sure it is not sealed off by the air filter etc) so the car should keep going - even with a defective pump or feed line/tank until the engine stalls at which time the float chamber will be totally bone-dry. You have a conversion carb, you do need to check that the carb vent is clear.

I am wondering whether this is actually a faulty ignition coil (or power pack if Marelli electronic). I know that when a power pack or coil is defective it will cut the spark, then after cooling down a bit it works again, eventually it packs up altogether. I think I might be for pulling off an HT lead and cranking the engine to see if there is a healthy spark when it stalls. No spark and you've got the answer. A two person job that one really. That intermittent coil/amp unit fault by the way is almost impossible to detect with diagnostic equipment, and I only know about because I ran TCs for years and experienced it myself.

GC

Yunko · Post by **Yunko** » July 17th, 2007, 1:14 pm

I will pay attention to the tach next time it happens. Also I forgot to mention I did replace the condensor, points, rotor, and cap. GC, what do you mean by HT lead, coil wire?

sumplug · Post by **sumplug** » July 17th, 2007, 1:32 pm

Three things to look at.
1/ Check the low tension lead from Coil to Distributor. A poor connection or faulty wire will overheat causing the engine to stop.
2/ There are some main relays in the engine bay. One maybe getting hot due to a fault internally or a bad connection, and this will cause it to fail, causing the engine to stop. Again, once cooled, it will work again. Feel relays to see if they are hot.
3/ You have a poor connection on the ignition circuit. Seen this a few times. Its enough to let the car start, but a wire overheats, and cuts the ignition circuit. Last one i did, was at the ignition switch itself. I would feel all ignition wires to see if they heat up.

Andy.

Yunko · Post by **Yunko** » July 17th, 2007, 1:45 pm

It seems we should be getting away from the fuel as being a problem but just one more thing before we move on the the ignition.
Repositioned the electric fuel pump below the tank and installed a clear fuel filter inside the trunk about 6 inches from the fuel pick up. Drove about 12 miles and the elec. pump started to make a loud noise. Looked at the fuel filter and it was bone dry. Pump was working but not pumping any fuel from the tank. Pump is not probably faulty because it did the same with another elect pump on.

sumplug · Post by **sumplug** » July 17th, 2007, 1:54 pm

When it faulters, take the sender unit out straight away and see if its blocked.

Andy.

Yunko · Post by **Yunko** » July 31st, 2007, 3:57 am

Here is where we are at. I was still having the fuel starvation problems as of last week but while driving one day the head gasket blew. I replaced it today and made my normal drive as always and the car did not hesitate or die from fuel starvation. Any chance the gasket going bad and finally blowing have any effect of the fuel problem I have been experiencing? From what I have been told the gasket just doesn't blow but wears slowly until it finally goes. Just a thought.

Post by **Guy Croft** » July 31st, 2007, 5:23 am

Seems conclusive under the circumstances...

I'll have to add it to my fault-finding list for 'engine drives 12 miles then dies..'!

GC

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USA Fiat 124 Spider 2 liter engine dies - fuel starvation?

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