4.0 SOHC first start idle 2 low

mred3 · Feb 14, 2016

Thanks for reply. This engine has no damper that i see this is suppossed to be on fuel correct ?

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mred3 · Feb 14, 2016

Also not sure if i tps on correctly

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mred3 · Feb 14, 2016

Pressure stay constant at around 60

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mred3 · Feb 14, 2016

My friends 2002 explorer has a daspot on his fuel rail with vac hose connect is this the one u mean?

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gw33gp · Feb 15, 2016

mred3 said:
Ok I thought I had a fuel problem but after finally getting a pressure tester its ok, what the truck is doing after setting a day it will start up for a few seconds and die then it wont start at all, let it set over night it will do the same also noticed it would backfire through intake like a flooded carbureted motor would do.

I had a similar thing happen when I removed the upper intake manifold and cleaned it with throttle body and carb cleaner. It fired right up initially and then died. I kept trying and sometimes it would fire and die. I got a backfire through the TB one time. I gave up and tried it the next day. It fired and died. After repeated tries and it would not fire but I did get another backfire through the TB. It set the next day because I had to go to work. I decided I was going to take it to the dealer the following morning because I checked out everything I could to resolve the problem. After I got home that evening, I tried it one more time. It fired right up and ran as if there was never a problem and has continued to run well for at least a year since then.

I am guessing some of the cleaner I used, got trapped somewhere in the intake and was fouling the O2 sensors or causing them to error when it started. It is possible after trying to start and sitting long enough that the cleaner cleared and the problem went away. I have no other explanation.

I doubt you have the same problem but you may be getting too much fuel into the engine causing a similar condition that I experienced. The black spark plugs is also an indicator of this.

mred3 · Feb 16, 2016

Fuel pressure stays at 55-60 psi hardly any drop at all.

mred3 · Feb 17, 2016

Just found I had 5&6 plug wires crossed holy crap! I thought the firing order was 123 then 456 not 465 damn well I hope this is the problem will go up Saturday to test. I just think that isn't my only problem but I can hope.

RonD · Feb 18, 2016

mred3 said:
Just found I had 5&6 plug wires crossed holy crap! I thought the firing order was 123 then 456 not 465 damn well I hope this is the problem will go up Saturday to test. I just think that isn't my only problem but I can hope.

Yes, common mistake even if you know correct order, which also isn't 465 if relating to 123
Coil pack
3 4
2 6
1 5
Front

So it is 5 6 4

The reason is that there are only 3 coils inside the coil pack, each coil sparks 2 spark plugs at the same time.
A V6 engine will have 3 sets of "matched pair" pistons to balance the rotation of the crank.
Two cylinder's pistons will be at top dead center at the same time, that's a matched pair.

On a V6 each pair will be 120deg from the next pair, 3 pairs 360deg(full rotation)
On a 4cyl, 2 matched pairs, 180deg apart
On a V8, 4 matched pairs 90deg apart
This balances the engine.

Firing order will tell you matched pairs on any engine
4.0l firing order is 1-4-2-5-3-6
split it in half 1-4-2....5-3-6
Put one half below the other
1-4-2
5-3-6

Those are the matched pairs for the 4.0l, 1-5, 4-3, 2-6

So the coil pack wiring makes more sense now
3 4
2 6
1 5
Front
1 and 5 are on the same coil in the pack, as are:
2 and 6
3 and 4

Because both matched pairs of pistons are at top dead center(TDC) at the same time firing both spark plugs as no ill effect.
One will be at TDC end of compression stroke so ready to ignite for power, the other at the end of its exhaust stroke, so spark won't hurt, but it is wasted.
Ford calls this system................................the Waste Spark system.

mred3 · Feb 20, 2016

Im getting 14 volts when key is turned at inertia switch then drops instantly to 9 volts injectors are pulsing to newly acquired noid light

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mred3 · Feb 20, 2016

I do have charger on explains 14 v

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mred3 · Feb 21, 2016

Once again after about a week of setting the engine started right up and died after 3 seconds.
Okay have good pulse from injectors tested 3 of them with a noid light and have great spark to plugs while cranking, now after clearing PCM and cranking its giving me codes p0231, P0232 and of course p1000, it seem the first two is contradictory ? high volt and low voltage.

still have 60 lbs fuel pressure.

RonD · Feb 21, 2016

Fuel pump relay could set both
The computer's Secondary circuit monitors the 12volts going to inertia switch and fuel pump.

This 12volts comes from the computer closing the fuel pump relay by grounding it.
When you turn on the key the computer's Secondary circuit will look at voltage on fuel pump's power wire, if 12volts then code P0232, voltage too high, should be 0 volts(actually I think it reads 4 or 5 volts).
Computer will then ground the fuel pump relay for 2 seconds.
Secondary circuit monitor should show 12volts only for those 2 seconds, then 0 volts, if still 12volts then code P0232 again.

After startup, RPMs above 400, computer will close fuel pump relay again, Secondary circuit should show 12volts again and stay that way, if it goes to 0 volts then P0231, low voltage.

You could hook up test light or volt meter to inertia switch and watch the power sequence to see if power is coming on for 2 seconds only, and then coming on and staying on after engine starts.

If power is being cut to fuel pump after engine starts then fuel pressure would drop and engine would die, as you describe.
You said fuel pressure is 60psi but does it stay at 60psi while engine dies?

EDIT: there is also a possibility of a PATS issue since PATS disables fuel pump power if activated, but you should get flashing theft light at that time.

mred3 · Feb 21, 2016

Ok yes it stays at 60

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mred3 · Feb 28, 2016

Well bad news I decided to do a compression check on a random cylinder which was #5 and it was 60lbs! so went on did check on the rest on same side #4 was 75lbs and #6 was 70lbs all done dry pulled #1 & #2 they both tested in the 140's stopped there since #3 a bitch in this truck to change a plug let alone doing compression check. So then did wet test on bank 2 #4 had 125lbs #5 85lbs #6 90lbs great they broke rings when installing now I got to send it back.
going test 3 today somehow.

mred3 · Mar 8, 2016

Finally received cam kit and its out when put the back side on to line up gtooves its setting about half inch off the deck where it should bolt on

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4.0 SOHC first start idle 2 low

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