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Discussion Starter · #1 ·
My GT jtdm refuses to start.
I had parked up on my parents drive and sat for a few minutes with the engine running. Then switched the engine off. My son was sat in the passenger seat and may well have pushed the seat back to get comfortable. Can't really remember.
After a few minutes tried to start it up and the engine turns over but doesn't fire.
I've checked a few things and run diagnostics but now I'm baffled.
Firstly cam belt is still in one piece.
EGR valve was blocked off years ago.
The only fault code relates to the EGR being blocked off.
Whilst running diagnostics engine RPM shows 450 whilst turning over. Crank angle sensor is working
The problem appears to be fuel related. Or should I say there definitely isn't any fuel at the fuel rail and the diagnostics read zero pressure against 450 BAR expected.
I suspect either the inertia cut off switch, the fuel pump in the tank or high pressure pump/regulator.
When I disconnect the fuel line from the tank to the fuel filter with the ignition on I'm getting fuel but not what I would call good flow.
I suspect if the inertia switch is activated I wouldn't get any flow?
Battery is now flat and charging.
Is there a reset for the inertia switch? I've read one post where somebody said there was a reset button at the battery terminal box. I can't find one anywhere.
All advise greatly appreciated.
Thanks,
Steve.
 

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To reset fuel inertia switch under passenger seat push the rubber cover on the top of it downwards. If a click is felt or heard, the switch was tripped. The switch is located under the seat, near the front in a central position (owner's manual details this).

The electric in- tank pump only supplies fuel for 2 seconds when ignition is first turned on or when engine is cranking or running (ECU gets signal from crank sensor) but only when the inertia cut off switch has not been triggered.
 

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Discussion Starter · #4 ·
To reset fuel inertia switch under passenger seat push the rubber cover on the top of it downwards. If a click is felt or heard, the switch was tripped. The switch is located under the seat, near the front in a central position (owner's manual details this).

The electric in- tank pump only supplies fuel for 2 seconds when ignition is first turned on or when engine is cranking or running (ECU gets signal from crank sensor) but only when the inertia cut off switch has not been triggered.
Hi Fruity,
The only thing under the front passenger seat is a plug. Looks like it's related to the airbag system so I left that well alone.
Steve.
 

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450 rpm sounds a bit high. Are the cam and HP pump turning when you crank it? Hoping I’m wrong but am thinking of stripped cam belt teeth.
 

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Discussion Starter · #7 ·
450 rpm sounds a bit high. Are the cam and HP pump turning when you crank it? Hoping I’m wrong but am thinking of stripped cam belt teeth.
Hi RT,
I was reading the 450 RPM from the graph. I was trying to read 4 parameters at the same time. All whilst my battery was dying.
I was more interested that it was reading something (confirming crank sensor working) so take the 450 RPM as a guesstimate. :hehe:

Cam belt is fine and HP pump is turning.
 

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Hi RT,
I was reading the 450 RPM from the graph. I was trying to read 4 parameters at the same time. All whilst my battery was dying.
I was more interested that it was reading something (confirming crank sensor working) so take the 450 RPM as a guesstimate. :hehe:

Cam belt is fine and HP pump is turning.
That’s good.

The flow from the LP pump is quite modest, but it should produce about 3Bar pressure if you ‘throttle’ it, and not contain air (shortage of fuel especially if the car is on a slope).

I think you need to add a couple more items to your list of suspects.

Injector leak-back: Pull return hose off injector and plug. A dribble from the injectors during cranking = seal failure.

Rail pressure sensor failure: Hopefully you would get a code, but maybe not during cranking (?) For a partial check: look at volts from it rather than pressure, do you see 0.5 with the ignition on?
 

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Discussion Starter · #9 ·
That’s good.

The flow from the LP pump is quite modest, but it should produce about 3Bar pressure if you ‘throttle’ it, and not contain air (shortage of fuel especially if the car is on a slope).

I think you need to add a couple more items to your list of suspects.

Injector leak-back: Pull return hose off injector and plug. A dribble from the injectors during cranking = seal failure.

Rail pressure sensor failure: Hopefully you would get a code, but maybe not during cranking (?) For a partial check: look at volts from it rather than pressure, do you see 0.5 with the ignition on?
Hi RT,
Mmm. The fuel coming from the tank to the fuel filter I suspect would be knowhere near 3BAR. I have no way of measuring the pressure. I can get myself a gauge when I go back to work.
Would you expect to see a constant flow of fuel for the couple of seconds that the LP pump runs? I ask because the fuel was spurting rather than a constant flow.
I'll be going down my parents in the morning to have another go at it.
I'm starting to think its a LP pump problem.

As far as rail pressure sensor failure. I KNOW there is no fuel getting to the rail.
I did the unthinkable and survived to tell the tale. :rotate:
Steve.
 

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As far as rail pressure sensor failure. I KNOW there is no fuel getting to the rail.
I did the unthinkable and survived to tell the tale. :rotate:
You absolute mad man ;)

Stupid question - got plenty of fuel in the tank?

I had an issue once that caused all my fuel to get dumped out of the filter onto a hot exhaust pipe at 70mph... Thankfully nothing caught fire, but because the tank emptied so fast the level sender didn't keep up, or the body-computer decided to ignore the input level and just hold a steady needle...

Anyway, the dash showed I had about half a tank when in actual fact I was completely empty... Stayed this way through a few key on/off cycles, and no surprise it didn't start with no fuel in the tank... when the hoses were popped off the top of the filter it made some gurgling sounds, but no flow of fuel!
 

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LP pump trouble does seem more likely than the other options.

My pump runs for longer, maybe 12 seconds, but the 1.9 might be different. If in doubt pull the pump’s relay and make the connection with a piece of wire so the pump runs continuously. It should then produce a constant flow of fuel. The HP pump only needs around half a Bar so if you can feel pressure with a finger over the hose outlet it’s probably good.
 

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Discussion Starter · #12 ·
You absolute mad man ;)

Stupid question - got plenty of fuel in the tank?

I had an issue once that caused all my fuel to get dumped out of the filter onto a hot exhaust pipe at 70mph... Thankfully nothing caught fire, but because the tank emptied so fast the level sender didn't keep up, or the body-computer decided to ignore the input level and just hold a steady needle...

Anyway, the dash showed I had about half a tank when in actual fact I was completely empty... Stayed this way through a few key on/off cycles, and no surprise it didn't start with no fuel in the tank... when the hoses were popped off the top of the filter it made some gurgling sounds, but no flow of fuel!
As it turns out not a stupid question at all:embarrassed::embarrassed:
Turns out the sender unit is telling me I have just under a quarter of a tank. Lying b*****d!!!
I've brimmed it up now and now showing full.
Question is will it get to just under a quarter of a tank and give me a false reading again?
Thanks for all of your help fellas.
Steve.
 

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As it turns out not a stupid question at all:embarrassed::embarrassed:
Turns out the sender unit is telling me I have just under a quarter of a tank. Lying b*****d!!!
I've brimmed it up now and now showing full.
Question is will it get to just under a quarter of a tank and give me a false reading again?
Thanks for all of your help fellas.
Steve.
Ive an In Tank pump if you get stuck
 
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