Warm start issues

[Jay-rod427]

Fuel voltage should have zero bearing on your issue.

Though for the record the way we set out JMS boxes up, is that they don't come on until they see boost. (pressure switch)



Its very easy to change the "throttle" response for the different modes in the tune. The entire slope/curve can be adjusted easily. So before you take the pedal apart, you may have a tuner adjust that for you.

But I like the super crisp responsiveness when hooning! HAHA Could prob make the case of desensitise the normal mode, and leave sport and track as is.

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[Tommy V]

Not saying in your case, but a lot of peoples "bucking/surging" at decent throttle stab is their foot on the pedal, especially like you said in track mode where it gets even more sensitive. I have pondered tearing apart the pedal sensor to find a stiffer spring for the pedal.

That sound plausible,but what is it,not keeping an steady throttle pedal?Its weird wot is fine and it dont do it all the time.I guess i could log it and take a good look at actual pedal position and commanded pedal position and see whats going on.To be honest i think its just opening to damm fast in track mode lol.

 

[Jay-rod427]

Correct your foot is inadvertently modulating the pedal a little bit, and each buck/surge makes you do it again brutal cycle. for sure check logs for pedal position. WOT throttle is fine because your foot is mashed to the floor with steady pressure on it. If trying to delicately hold steady partial throttle in the upper rpm's I will move my foot slightly to the right up against the trans tunnel. Then foot has two bracing points (heel, and side of foot) to steady it from unwanted movements.

 

[Tommy V]

Correct your foot is inadvertently modulating the pedal a little bit, and each buck/surge makes you do it again brutal cycle. for sure check logs for pedal position. WOT throttle is fine because your foot is mashed to the floor with steady pressure on it. If trying to delicately hold steady partial throttle in the upper rpm's I will move my foot slightly to the right up against the trans tunnel. Then foot has two bracing points (heel, and side of foot) to steady it from unwanted movements.

Yea that makes sense!!!

 

[jvandy50]

OP, maybe ask some of these guys.

http://www.mustang6g.com/forums/showthread.php?t=32639&highlight=long+start

 

[DeepImpact 5.0]

OP, maybe ask some of these guys.

http://www.mustang6g.com/forums/showthread.php?t=32639&highlight=long+start

Great find!! Starting to read through it already and I see the same issue as me described multiple times, maybe I can figure this out lol. Thanks!

 

[jvandy50]

No problem man, hope that helps and maybe some of those guys have fixed theirs :cheers:

 

[Bestia]

Great find!! Starting to read through it already and I see the same issue as me described multiple times, maybe I can figure this out lol. Thanks!

hi is there any reason why i cant read the linked thread?

 

[jvandy50]

hi is there any reason why i cant read the linked thread?

It will not let me pull it up either, possibly something to do with the update?

 

[Burkey]

Hey guys, seeing if any of y'all have any ideas about a problem I have been running into. After driving for a little and parking my car, it has no problem starting for about an hour or so. If it sits for an hour or more, like literally up to five hours, it has a hard time starting. If it sits overnight, it has no problems at all starting. I have no clue as to what the problem could be, otherwise the car runs great once started. Thanks for any ideas

First question: What breed of supercharger are you running and does it have aluminium fuel rails that are directly bolted to the blower?

If that’s a yes, there’s chance that you’re suffering from vapour lock.

Second question: Do you have a non-return valve fitted to your fuel pump or fuel system?
If not, I’d almost guarantee that the issue is in fact vapour lock.

Gasoline has a low boiling point when it’s not under pressure. Add the heat of the heads being transferred directly into the rails and you have yourself the perfect recipe for a slow starting car.
Fitting phenolic spacers to my vehicle (and a few others with the same issue) instantly cured the problem.

 

[Angrey]

Is the car lugging to warm start? Or is it just spinning and not getting fuel?

I recently replaced my starter. Similar issues. Car sits overnight, fires right up. Go to grocery store 10 minutes away, come out, car struggles to start. After replacing the battery and scratching my head chasing what I thought was current and voltage issues, I mentioned it to my dad and he instantly said "sounds like the starter."

 

[ProChargerTECH]

Holy wow, this thread is from 2017.... how did this get dug up?

 

[Bestia]

i have the same issue but mine is more so there is no other symptom other than after being driven then sitting for 10 min, it will not ground the injectors for whatever reason through the PCM, be it an internal fault or some other instruction or handshake to the ecu (as one example) that instructs it not to inject fuel.

anyone experienced this before

 

[Bestia]

First question: What breed of supercharger are you running and does it have aluminium fuel rails that are directly bolted to the blower?

If that’s a yes, there’s chance that you’re suffering from vapour lock.

Second question: Do you have a non-return valve fitted to your fuel pump or fuel system?
If not, I’d almost guarantee that the issue is in fact vapour lock.

Gasoline has a low boiling point when it’s not under pressure. Add the heat of the heads being transferred directly into the rails and you have yourself the perfect recipe for a slow starting car.
Fitting phenolic spacers to my vehicle (and a few others with the same issue) instantly cured the problem.

HI Burkey noticed your an aussie too

I have a similar problem - no injector pulse once switched off and warm (edelbrock 2300 with aluminium fuel rails direct to blower) it will crank just not start - if you leave it for an hour it will start when cold and run perfectly no issues until you switch it off for 10 minutes and then it will crank but wont start- so frustrating

just ordered a
8mm 5/16" One Way Non Return Fuel Line Check Valve
to see if it sorts out my issue - my ford dealer was saying its the ecu not providing a ecu handshake to fire the injectors when hot - do you still think this could sort out my issue?

never had this issue before, i only recently replaced the clutch - needless to say all sensors, wiring etc has been checked and they still cant figure it out

 

[Burkey]

HI Burkey noticed your an aussie too

I have a similar problem - no injector pulse once switched off and warm (edelbrock 2300 with aluminium fuel rails direct to blower) it will crank just not start - if you leave it for an hour it will start when cold and run perfectly no issues until you switch it off for 10 minutes and then it will crank but wont start- so frustrating

just ordered a
8mm 5/16" One Way Non Return Fuel Line Check Valve
to see if it sorts out my issue - my ford dealer was saying its the ecu not providing a ecu handshake to fire the injectors when hot - do you still think this could sort out my issue?

never had this issue before, i only recently replaced the clutch - needless to say all sensors, wiring etc has been checked and they still cant figure it out

Hey mate, hard to say for sure.
I think I saw elsewhere that you’re Lund tuned. If that’s the case, it’s been my experience that Aussie Ford dealers can’t interrogate the car whilst the tune is loaded. I tend to think that they’re either full of shit, or, they have some method that others don’t.
Does the car smell like it’s been dumping a heap of unburnt fuel when you eventually get it to start?
Are you running the DW400 pump?

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