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Topic: Start and die with Ford 5.0 (Read 1207 times) previous topic - next topic

Start and die with Ford 5.0

Greetings;

I just thought I had some auto headaches behind me when this happened.  I went to start another old Ford we have (5.0 engine) and it promptly died after running for about 4 seconds.  I repeated the process a number of times and managed to keep it running at high idle--sounded awful and smelly.  Once it warmed up a little, it actually sounded a little better, but still died upon release of the pedal.  The car sat idle for a week in the garage before this new headache occurred and was fine before that. 

I changed the fuel filter and battery because both were old.  No change.  I bought a new Trottle Position Sensor, no change.  I checked/cleaned the EGR and IAC and both looked OK.  I ended up removing the IAC motor can from its mount and physically depressed the IAC plunger within the cylinder.  That source of air allowed the car to run well and it seemed quite normal as long as I did that.  I swapped another identical IAC (one from the Tbird) into the car, but the problem persists.    The 2 codes I thought were important are 1) TPS signal out of range 2) HEGO (HO2S) sensor voltage low/ system lean.  The car has had the 34 code (EGR) for years--I ignore it. 

JR      Stumped!!

Start and die with Ford 5.0

Reply #1 –
Ill put my money on the fuel pump hose being cracked. Same/Similar thing happened to me.
[SIGPIC][/SIGPIC]

Start and die with Ford 5.0

Reply #2 –
Simple to check the fuel pressure that will eliminate or prove the hose is split!! So do that and post back with results!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Start and die with Ford 5.0

Reply #3 –
what kind of smelly? Rotten eggs sort of smell could be a clogged catalytic converter.

Start and die with Ford 5.0

Reply #4 –
OK Tom and Beast50!  I have all day today to work on this engine.  With the key "on" and engine off, the fuel pressure is a steady 38psi.  There is an air release button on the fuel gauge line and when I pushed that, the gauge pressure dropped to zero and does not come back (until you key off and on again).  I removed the IAC from its mount and with the key on--I observed the plunger move inside its body--guessing maybe 1/4 inch.  I casually checked all the engine management items I see in books and looked at vacuum hoses and couldn't see anything amiss (also climbed on top of this engine and checked the rear--PCV lines etc.).  I removed the fuel regulator vac line and observed no fuel leakage there.  The smell with the engine was that kind of smell (cars years ago) from a rich carburetor --like the choke was stuck on.  This is an 1989 Lincoln Towncar. 

Any ideas? 

John R

Start and die with Ford 5.0

Reply #5 –
swap in a tps,
FP at that psi initially shows ok, doesnt tell you much while under a load with tranny in D but thats not the point i know.

IF you have fuel and spark, and your having to help it run by hand, its a good chance the TPS will fix,,, check out my diy link for test steps.
***and*** how to mount it so its adjustable.

while you crank, you should "feel" each injector clicking.  You can also back prob a couple injector plugs with a test light and see if the computer is sending the ground signal for them to pulse.  it is very difficult to know if an injector is stuck open or not, feeling by hand the click of the solenoid says its working but doesnt tell you if its partially staying open.

pull out all the plugs and note any odd plug looks.

check to make sure you have blueish white spark by sticking a plug in there,, anything but blue / white spark points to a tfi / pick up module (weak spark)

smell oil to see if your adding fuel to the oil pan

disconnect exhaust at a common point upstream of the catalytic,,, it may be clogged.

introduce a vac leak and see if the car stays running...


just a few thoughts, sorry its scattered, just typing what hits me..

Start and die with Ford 5.0

Reply #6 –
this might be useful... if needed for fuel tests.

at your EEC diagnostic test connector, ground the tan light green wire
turn on your key
this will make the fuel pump run continuous.  turn off key and it will take a few seconds to turn off as in when the eec relay cuts out.

Start and die with Ford 5.0

Reply #7 –
get a can of carb cleaner and spray around the intake , when you get it running and if you have to help it run,  spray carb cleaner along the intake both upper and lower.  Hit various vac lines as well and along the vac line wire looms.

if the engine suddently changes in rpms, your finding a vac leak.
 

Start and die with Ford 5.0

Reply #8 –
OK!!  From advice ---I removed the vacuum hose to the MAP sensor and stuck a pencil end in the hose opening---and started the engine.  The vac hose had a significant amount of vacuum in it I noted.  Although the engine struggled to run, it ran and stumbled on low idle with slight acceleration pedal help.  Big improvement.  From there I swapped the MAP from the T-Bird into the Lincoln as they are identical---and the Lincoln ran fine.  So this problem is solved!  In fact, I'll put the replacement MAP on the T-Bird.  It's hard to believe that such a part can mess up an engine!!  Thanks all for input....  The MAP on the T-Bird hangs on the firewall, so it was easy to remove for swapping. 

JR