Help! Engine cranks but wont start

[GetMeMyStogie]

All of a sudden, my engine wont start. I turn the key on, and all of the dash lights check out normally. I turn the key to crank, and the motor cranks over, but does not start.
I've had a problem with my IAC, and perhaps it's finally failed outright - but if that's the problem, shouldn't I be able to start it with the the throttle slightly open? Or, if it's stuck wide open, wouldn't it rev crazy high? Either way, shouldn't it still start?

What else can I check? The camshaft position sensor plug seems firmly attached. I seem to be getting fuel - pressed the schrader valve on the fuel rail, and lots of gas spewed out.

Is there a crankshaft sensor? Where is its plug located?

Anything else I should check?

[MOTOWN]

i would check the fuel pump, and filter to ensure flow, and pull a sparkplug to see its getting power/spark, when you turn the key listen for the fuel pump to see if its priming

[CBT]

i would check the fuel pump, and filter to ensure flow, and pull a sparkplug to see its getting power/spark, when you turn the key listen for the fuel pump to see if its priming

Why? Just unhook a coil.

[Blackened300a]

Whats the red LED on the top of the dash doing when you crank?

[MOTOWN]

Why? Just unhook a coil.

because unhooking a coil will not tell you if a spark plug is bad/fouled out/broken

[CBT]

because unhooking a coil will not tell you if a spark plug is bad/fouled out/broken

True, but a fouled plug will not stop the engine from starting. You would have to have about 8 out of 8 bad plugs for it to completely not start.

[MOTOWN]

True, but a fouled plug will not stop the engine from starting. You would have to have about 8 out of 8 bad plugs for it to completely not start.

process of elimination bud! that way you know the plugs are not the problem, doesnt cost anything to pull and inspect them.;)

[Blk Mamba]

A lot of wasted time if you ask me, ^^^^, check my post from about a year and a half ago, lots of information in there, my problem turned out to be a crushed wire bundle, behind the driver side cam cover.

[MOTOWN]

in order to find that problem you started checking related connections ,wires etc

[JAYSILVER04]

A lot of wasted time if you ask me, ^^^^, check my post from about a year and a half ago, lots of information in there, my problem turned out to be a crushed wire bundle, behind the driver side cam cover.

+1..I had that happen a couple years ago.

[GetMeMyStogie]

+1..I had that happen a couple years ago.
Seriously? Crushed wire bundle? That seems very odd. In my case, I drove to work and parked as usual, with no hint of a problem. I come out 8 hours later, and she cranks, but won't fire up.

[MOTOWN]

Seriously? Crushed wire bundle? That seems very odd. In my case, I drove to work and parked as usual, with no hint of a problem. I come out 8 hours later, and she cranks, but won't fire up.


maybe your valve cover got mad at your "wire bundle" while you were woking ,and all hell broke loose! :lol:

[JAYSILVER04]

Seriously? Crushed wire bundle? That seems very odd. In my case, I drove to work and parked as usual, with no hint of a problem. I come out 8 hours later, and she cranks, but won't fire up.

Mine was chaffed by the stud on the wiper arm. It cut out while I was driving at like 40 mph..Came to a rest and tried to restart...nothing..Had it towed to the Dealer and they found the wire shorted out from the wiper arm. re-taped it and re-routed it and its been fine ever since. That was over 2 years ago and the car only had 9k miles on it at the time...I had it for 2 days at that point. I was replacing my 73k mile MM and while I was sitting on the side of the road in 100 degree weather, I was second guessing my purchase:lol:.

[ROCOB]

I can tell you that it is probably not the circuit that controls your PATS. That was the cause of my failure after my purchase in AZ. There was a chaffed wire bundle that was the culprit in my case. The car will not turn over if this circuit is disrupted. It is the #8 fuse in the fuse box by your nearest your left knee when driving. This fuse protects the circuit for the fuel pump, PATS, and COPs.

I would think that it is fuel related, could be a failed fuel pump, FRPS, or least likely the inertia switch.

ROCOB

[MOTOWN]

its turning over, but not starting so its probably fuel, or spark related, as i stated this is where the process of elimination comes into play, unless you tow it to a shop, i fix my own so thats where i would start.

[Dragcity]

Yes, there are a lot of sharp edges near that wire bundle. I placed a section of heater hose there to to keep the wires away. Over time it "trained" them down so I don't need it any more.

I would look there...

As always:
1) Fuel
2) Air
3) Spark

[RacerX]

Mine was chaffed by the stud on the wiper arm.:lol:.
CBT was on your wiper arm???

[TFB]

Guys Stogie stated he has a good fuel spray at the schrader valve on the fuel rail, so that should eliminate the pump & inertia switch... Also it was running fine just prior, so the plugs can be eliminated, I'd check for spark and work from there... If there is no spark, problem could be harness related as mentioned, or maybe the crank sensor also mentioned...

[fastblackmerc]

Check the wire harness on the drivers side at the rear of the cam cver. There is a stud that my cut or abrade the wires in the harness. I believe there was a TSB about that.

If that is the problem, fix the wire(s), move the harness away from the stud, cover the harness with either some heater hose or split loom and get a vacuum cap to cover the stud.

[JOEMERC]

should be able to hear fuel pump buzzing in tank,while some one turns key on .maybe the fuel pump is bad if quiet ?

[fastblackmerc]

should be able to hear fuel pump buzzing in tank,while some one turns key on .maybe the fuel pump is bad if quiet ?

See posts #1 & #18

He said he had fuel under pressure at the schrader valve in the fuel rail so doesn't that rule out a fuel problem?

[justbob]

Seriously? Crushed wire bundle? That seems very odd. In my case, I drove to work and parked as usual, with no hint of a problem. I come out 8 hours later, and she cranks, but won't fire up.
This has been the culprit on a few hundred Marauders (or more) and is very well known around here.

I thought I read that there were infact two different versions of the PATS, where this earlier version DID let it crank? Have you swapped keys and tried?

ECM fuse?

[TFB]

^^^^ The PATS on my '98 Grand Marquis allows it to crank but doesn't start, I guessing the Marauders use similar system... The ECU in some systems provides ground for the solenoid, so if PATS ain't happy they won't even crank...

[babbage]

I know he says it has fuel pressure, but I like to spray a good 10 seconds of starting fluid into the intake and then see if it starts...

[Blackened300a]

Hence why I asked what the LED on the dash is doing. Its possible the resistor in the key failed. My CV would crank with no start when I had a regular key made.

[Blk Mamba]

Never use starting fluid, it's dry, use WD-40, it has an oil in it that keeps the Cylinders lubricated, and 10 seconds could do a lot of damage.

[TFB]

. Its possible the resistor in the key failed. My CV would crank with no start when I had a regular key made.
There is no resistor in a Ford key, they use transponders...

There is a antenna positioned around the ignition tumbler which allows the PATS module to send a small signal to the transponder in the key... The key in turn sends a signal back to to the antenna, into the PATS module and on into the PCM... If the signal matches the reference stored in the PCM, it allows the injectors to fire so the engine can start...

[GetMeMyStogie]

I took it to a nearby shop this morning and it turns out that it was indeed the IAC valve. Apparently it shorted out or something, causing the ECU to dump way too much fuel, flooding the engine and fouling all of the plugs. The shop changed the plugs, and dried out the excess gas. With the IAC disconnected, it starts and runs fine. Plug it in again, and it floods the engine right away. They wanted $300 to put in a new IAC, on top of the plugs and diagnostic, but I'm sure I can find one for less than half that.
Bonus: the car is quite drivable with the IAC unplugged, though it does idle a bit too high (1000-1200 rpm in drive)


Thanks for all the suggestions, fellas! I'll have to look at my wire bundle to make sure that doesn't sting me :)

[Dragcity]

See, you knew what was wrong before you even asked..... Awesome that you know your car so well.

[MOTOWN]

I took it to a nearby shop this morning and it turns out that it was indeed the IAC valve. Apparently it shorted out or something, causing the ECU to dump way too much fuel, flooding the engine and fouling all of the plugs. The shop changed the plugs, and dried out the excess gas. With the IAC disconnected, it starts and runs fine. Plug it in again, and it floods the engine right away. They wanted $300 to put in a new IAC, on top of the plugs and diagnostic, but I'm sure I can find one for less than half that.
Bonus: the car is quite drivable with the IAC unplugged, though it does idle a bit too high (1000-1200 rpm in drive)


Thanks for all the suggestions, fellas! I'll have to look at my wire bundle to make sure that doesn't sting me :)

glad to hear you got this sorted out bud! iac valve go figure:eek:

[Blackened300a]

There is no resistor in a Ford key, they use transponders... .

Thats what I meant, just wrong wording.

[babbage]

Never use starting fluid, it's dry, use WD-40, it has an oil in it that keeps the Cylinders lubricated, and 10 seconds could do a lot of damage.

Well perhaps not 10 seconds, but a good dose to see if it as least runs.

IAC valve could have been taken apart and cleaned, I'd clean the Tbody, intake too etc.

[swagjack85]

I'm having this same problem with my I was driving all sudden the car dies while driving now it won't start & sometimes it do it seems like I was not getting any power when I turn the key on so what was your problem so I can try fix my car

[fastblackmerc]

I'm having this same problem with my I was driving all sudden the car dies while driving now it won't start & sometimes it do it seems like I was not getting any power when I turn the key on so what was your problem so I can try fix my car

Go back and read the posts. OP has posted what fixed his problem.

[martyo]

I'm having this same problem with my I was driving all sudden the car dies while driving now it won't start & sometimes it do it seems like I was not getting any power when I turn the key on so what was your problem so I can try fix my car

AJ I was thinking about your car last night.

I can't help but winder whether the exhaust guy welded on your car without disconnecting the battery he might have fried your PCM....