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Discussion Starter #1
Well I am running out of ideas - trying to diagnose a cold-start problem on my 4.6 modular - is there anyone in the CT/NY area familiar with the old Accel7 who could help me out?

The car seems to work fine in the summer but I can barely get it started now the temperatures are low - a few coughs and it's getting fuel for sure but it just won't run.

Maybe this is a coincidence though and there's something deeper at play....
 

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sounds like theres no cold start enrichment , id check temp sensor for the ecu , the sensor for your gauge and ecu should be different
 

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Discussion Starter #3
There's plenty of fuel - I can smell it. the ECU temp sensor is tucked under the manifold - not ideal but at least it's at ambient temperature - if anything it should think the engine is colder than it is, not warmer. I'm going to change the plugs and check I have spark on them all - this is a mystery - I would expect it to run badly, but not fire at all seems suspicious.
 

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well then next thing id look at is fuel pressure and volume , low pressure or volume will cause a no start problem , and can cause flooding because there isnt enough pressure or volume to allow the injectors to atomize the fuel properly it would come out of the injector as a drip instead of a spray pattern . i will do some more digging and get back to you
 

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Discussion Starter #5
well then next thing id look at is fuel pressure and volume , low pressure or volume will cause a no start problem , and can cause flooding because there isnt enough pressure or volume to allow the injectors to atomize the fuel properly it would come out of the injector as a drip instead of a spray pattern . i will do some more digging and get back to you
thankyou. I was thinking of pulling the injectors and seeing what they look like - atomization does seem to be a likely candidate. When it starts, it runs like it always ran so I wasn't thinking fuel rail pressure would be a problem - It's 40psi according to the gauge.
 

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as per ford the fuel pressure engine running it should be 35-50 lbs , key on engine off the pressure should be 25-40 psi , so next id change the fuel filter to see if its a volume problem , the accel 7 system is a tuneable system and the tuning software is availible from accel ,
 

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Discussion Starter #7
as per ford the fuel pressure engine running it should be 35-50 lbs , key on engine off the pressure should be 25-40 psi , so next id change the fuel filter to see if its a volume problem , the accel 7 system is a tuneable system and the tuning software is availible from accel ,
The Accel system WAS tunable, but Holley bought them and cancelled all support so I am on my own unless I can find someone in CT who still knows how to handle it.
 

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Discussion Starter #8 (Edited)
Ongoing saga update.. I was trying to diagnose the cold-start problem and got to the point that the car just wouldn't start - then I started getting a "clicky starter" problem - when the starter doesn't engage but goes "click click click click" etc.

So, meh - pull the starter and the front ball bearing is missing - the shaft has pushed through the end. Order a starter and while I'm waiting, pull of the manifold and clean all the injectors, plus new plugs.

Replace the starter and what do you know - still clicking so I pull the plugs wondering whether I have a hydraulic lock due to all the fuel that's not being burnt.

Still clicks - but this time luckily I happen to notice "magic smoke" in the truck where my EFI unit is.

Now to recap - we now have an engine with no manifold, injectors are disconnected as is the TPS etc.

Next step of course is to unplug the computer as magic smoke means I have a short to ground somewhere - in doing so I find that one of the pins has welded itself onto the computer connector and stays attached when the plug comes out...

With the computer unplugs, the motor turns over fine - no more click. Plugs back in and still turning fine.

At this stage I start calling people about an EFI rewire...

With nothing to lose, I put the injector harness back on, button up the manifold and reconnect all the sensors, then pull the computer, wrangle the pin off the connector, solder some wire to it and put everything back together - no burns or melts on the EFI computer board - everything looks perfect.

The welded pin/melted wire was a ground from the cam position sensor?

Turn the key and what do you know - it starts on the 2nd rotation.

Again, and again - perfect.

I have no idea what's going on now. How can a ground on a cam position sensor short enough to stall the starter motor (and no melted wires near it for it to short to!

Fingers crossed this was some obscure problem but I am suspicious...

UPDATE: One day later and we are back to no-start :-(
 
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