Sasha 2008-08-19 19:39:26
87 F150, 302 EFI, duel tanks.
The problem is that it starts but stalls right away. If I keep the
pedal down it will fast idol then almost stall then serge and almost
stall over and over again. I believe this is a fuel problem because it
seems to have started soon after running the rear tank dry. I changed
the fuel filter on the front frame and the gas looked rusty red and
cloudy and a fine sediment when let it sit in a glass. I have a crappy
Hynes book but I can’t get much information from it because it covers
1980-1986 and I don’t see the same components under my truck. And it
never mentions a particular year. I can’t determine if I have in the
tank fuel pumps, where the high pressure fuel pump is, the reservoir,
and the fuel pressure regulator. And if a fuel pump can be week and
or clogged. I plan on removing the rear tank tomorrow and try to clean
it out and run it with fresh clean fuel. If that works I will do the
same to the front tank. But I really don’t know how to troubleshoot
this problem. Not even sure it is a fuel issue But i think it is. Can
anyone please give me some expert advise? I really need it!!!
Thanks Rick rittt@ nospambellsouth.net
Rodan 2008-08-19 20:25:57
The problem started soon after running the rear tank dry.
It starts but stalls right away. If I hold the pedal down
it will fast idle then almost stall then surge and almost
stall over and over again.
I changed the fuel filter on the front frame. The gas
is rusty red and cloudy and leaves a fine sediment when
left to settle. I don’t know whether I have the in-tank
fuel pumps. I don’t know where to find the high pressure
fuel pump, the reservoir, or the fuel pressure regulator.
I plan to remove the rear tank tomorrow and try to clean
it out. If that works I will do the same to the front tank.
But I don’t know how to troubleshoot this problem. Not
even sure it is a fuel issue But i think it is. Can anyone
please give me some expert advise? I really need it!!!
It does sound like it’s starving for fuel if it won’t go above a
fast idle no matter how hard the pedal is pushed.
If it was a bad tank pump it would still run okay on the other
tank. Before dropping a tank, run the output of the filter into
a bucket for a couple of seconds to see if it is being pumped.
This is a good time to reconfirm that the filter is not reversed.
Buy an up-to-date manual or look up the vehicle systems in
the reference department of a library.
Mombu 2008-08-19 20:26:03
Check eBay Motors for the “Ford Service Manual” for your truck. (Might
be termed the Light Truck Shop manual) You want the Service Manual, not
any ‘repair’ manual. I believe you will find one easily and it won’t be
expensive. If you do buy one on eBay, make sure your seller ships it to
you using Media/Book rate…insist on this or you will pay some
outrageous shipping fee. You might still be able to buy a new one at
the Helminc dot com site. Possibly your local library might have
Sasha 2008-08-19 20:26:08
I no longer believe that it is a fuel problem. I put new gasoline in
the rear tank, started and kept it running about 3-5 minutes with the
accelerator. It runs very rough and serges even with the pedal held
steady. same with either tank. How about the EGR valve? It looks like
a real pain in the a** to replace since it is located behind the
engine and I can’t even see it. I think it is about $75.00 bucks.
Thanks Dave! I just ordered a Helms manual
Any thoughts and suggestions appreciated!
Ken finney 2008-08-19 20:26:11
If you think the EGR valve is a PITA to get to on a 302, try a 460!
My 1988 F-250 is in the shop right now for surging and stalling, and the
first thing they found was the oxygen sensor was ALMOST out of spec enough
to set a trouble code. According to them (and I have anecdotal evidence
that they are correct) the EEC-IV engine computer in later years (like 1994)
will set a trouble code BEFORE the oxygen sensor makes the engine start
running bad, but in earlier years (like 1988) the engire will run poorly due
a drifting oxygen sensor long before it drifts enough to set a trouble code.
Sasha 2008-08-19 20:26:14
Thanks for the reply!!! it seems that I was wrong about the EGR
location. It is right in front next to the Air intake valve. I don’t
know what that thing is directly behind the intake manifold.
Please advise here the final outcome of the repair of your 88 F250.It
sounds like the same symptom. I only need to get 6 more months out of
this vehicle then I hope to sell it for about $800.00 I have had it
since it had 25K miles on it and it now has around 77K . needless to
say I don’t want to just throw money at by changing parts. I worry
that a repair shop will do that and argue that they were all the
cause. I do plan on replacing the plugs,wires,coil rotor and dist cap
Rick. email . . . . email@example.com
On Thu, 19 Oct 2006 20:02:16 GMT, “Ken Finney”
Ken finney 2008-08-19 20:26:15
I bought mine with 77K on it. The stupid design big block coolant seals in
the timing cover went at about 90K. The alternator went at about 100K. The
EGR valve went at about 120K I was hoping to get to 150K without major
repairs, but about 130K has the C6 transmission replaced (and it didn’t need
it!!!). A word to the wise: a intermittently locking and unlocking fan
clutch feels (and sounds) a lot like a slipping automatic transmission. So,
the transmission might have lasted another 100K or could have failed the
next day, no way of telling. The replacement did upshift a lot faster and
upped my city mileage quite a bit. At about 140K I started getting a bad
exhaust leak due to broken exhaust manifold bolts (a known big block
problem). At about 150K the front end got really wobbly and required a
major rebuild. At about 155K it started missing and stalling, and while
replacing the plugs, wires, cap, and rotor helped, I finally decided to let
the experts take a look at it. Your symptoms are worse than mine, I
understand there is a little plug-in module in the distributor that can
cause all sorts of problems like yours, and isn’t too expensive to fix.
Mike h 2008-08-19 20:26:34
You need to locate two things. One is the fuel pressure regulator, and
the other is a valve on the fuel rail that allows you to check
Both items will be on the fuel rail for your engine. The regulator
should have a vacuum line going to it and you should remove the line
from the regulator and inspect it. It should be dry and have no fuel
inside it. If there is fuel in there, your fuel pressure regulator has
failed and is dumping fuel into the intake manifold causing it to flood
and run very rich.
If that’s not it, you can verify the fuel pressure at the rail which
will validate that your fuel pump is doing o.k. You can rent a gauge
that will hook onto that fitting from some auto stores, others you pay
$25 and you have your own gauge. Fuel pressure should be around 38psi
as soon as you turn the key on and maintain pressure when the engine is
started and running.
If pressure is not maintained, you could have a bad fuel pressure
regulator, a bad fuel pump, or a plugged fuel filter.
Kenb 2008-08-19 20:26:40
That was my first thought, as I’ve had a fried ignition module cause
almost the exact same symptoms in my old 88 Ranger. The engine will start
right away, and then stall immediately afterwards, leading me to think that
the engine ran out of fuel immediately after starting.
A mechanic friend explained the problem like this: the ignition module
has two modes of operation, a starting mode that applies no spark advance,
which changes over to a second mode immediately after the engine starts for
normal engine operation. When the second mode circuitry succumbs to
corrosion or whatever, the engine will start up fine on the first (starting)
mode and then stall immediately when the second mode fails to take over. He
was right on the money in my case, as my truck started right up and ran fine
after I followed his advice.
This sounds quite similar to the problem experienced by the original
poster, with the only difference being that he was able to keep it running
for a little while after it started up, which is something I wasn’t able to
do for any more than a few seconds.
My gut instincts still point to the ignition module though, because my
engine definitely did sound like it was running out of gas when it was
stalling out. As a result, I also spent a great deal of time concentrating
on the fuel system before my buddy tipped me off about the ignition module.
Sent to you by Ken at firstname.lastname@example.org
Change “who?” to “b2” to reply by e-mail
Sasha 2008-08-19 20:26:41
Thank you Mike!!!!!
That’s what I’ll do in the morning, check the fuel regulator and look
for the port on the fuel rail and try to buy the appropriate gauge. Is
the fitting before the Fuel regulator or past it?
Today i replaced the plugs, wires, Dist.cap and rotor.Fuel filter is
Mike h 2008-08-19 21:13:06
The fitting is somewhere along the fuel rail. Not sure where but the
fuel pressure regulator (FPR) on Fords is also usually bolted to the
fuel rail. Usually there are two lines to the fuel tank. One is fuel
to the rail, one is return to the tank.
In this picture of a ford engine, the fuel pressure regulator is the
silver canister with a pipe sticking out the top (for the vacuum line)
on the middle left side. The view in the picture is from the rear of
the engine. My guess is it’s similar to what’s on your motor as that’s
what’s on my 89 ranger, and my 90 and 93 tbird.
I don’t see the fitting there, but it’ll be there as it’s used to
relieve fuel system pressure when servicing it. The fitting is one
just like used to fill the air in your tires. It looks like you could
hook an air hose to it, but don’t do that. it’s called a schrader
valve I believe.
Joe 2008-08-19 21:13:16
Right there is the place to stop and put on a fuel pressure gauge. You can
just remove all the mystery in about 5 seconds. Fixing cars is easy when you
I bought one for about $30 at advance auto, but you can probably b** one at
Autozone. I just like having one around, it’s so handy.
Sasha 2008-08-19 21:13:20
Thanks Joe, It would be a lot easier if I had a better manual than
that pos Hynes. I have a Helms coming in the mail and I don’t know how
much better it will be. I plan on doing the Pressure test. I also want
to trouble shoot this truck because I don’t want to waste money on it
since I plan on selling it in about three months. This is not my
primary vehicle so I can take the time to work on it. If I replaced
everything that was suggested It would be a total loss, ha! This is
probably a good why for me to get some practical automotive repair
experience. I need the suggestions though because I don’t have any
mechanic friends to ask.