1993 SHO Starts and runs fine, but when hot will not run correctly

[Plasticmatt477]

Hi everyone,

I'm new to this forum and think its GREAT that there is a forum on JUST SHO'S!!! I appreciate you letting me join and ANY help with this issue would be GREATLY appreciated!

I have a 1993 Ford Taurus SHO (3.0L 24v DOHC) and for the past few months it has had the same issue. When the engine is cold and I start it, it fires right up and will run all day no problems, but once the engine is warm or hot and I shut it off it will still crank, but will either misfire and die off (real sluggish) or will just continue cranking. If I let it sit until cooled down, it will fire right back up and idle, run, accelerate... just fine. I have replaced the ignition switch (Advanced auto reccomended) and been looking at either the coil pack or TFI Module as a possible problem, but I am by far not an expert!

Thank you again!,
Matt

P.S. I'll post some pictures of my SHO too (just so people can see her) Hunter Green with leather Tan interior...

 

[jayro]

Welcome to the forum. Have you tried pushing the gas peddle all the way to the floor and trying to start it? Without going into alot of detail, these engines will flood at times when hot and flooring it will cut off the injectors while cranking. Another heat related no start issue could be your Crank Sensor. A leaky water pump can leak on it and cause it to overheat. Has it ever quit while you are driving it, or just doesnt want to restart? Have you pulled codes? even if the CEL isnt showing there could be some stored.

 

[rbruso]

Another thing to check is whether the gas tank is venting properly. When the car refuses to start open the cap and see if there is a lot of pressure built up.

After a trip to Tucson last week I had this happen twice. I had been smelling fuel vapors after long runs for a while, with the car refusing to start once, and had cleaned out the small orifice in the fuel vent line near the charcoal canister. In my case, it turns out I have a canister purge solenoid stuck closed. I've been running with it disconnected since Sunday without a problem. New solenoid is on the way.

 

[zblackbeast]

Im going to go with either an ignition module or cam sensor. When was the last 60k/tune up done?

 

[Plasticmatt477]

First I wanted to thank you for answering me so fast!

I have not tried flooring the pedal, but will def try that and see what happens. It does not quit while running... the only time it won't run is when its hot and I try to start it back up without letting it cool down. When I do this it will idle erratically sometimes and feel like it wants to start, but can't (usually just keeps cranking).
I have not pulled the codes, but I am actually going to take it to Auto Zone and have them pull the codes bc i don't have a reader... The CEL does come on but oddly it only comes on when the engine starts warming up (typically on the highway). The CEL has done this since I bought the car about 6 years ago.

Is a crank sensor a hard replace? Because if its cheap and simple I might just pick one up while i'm at autozone.

Thanks again,
Matt

p.s. If that pic on your profile is your sho... it looks AMAZING!

 

[Plasticmatt477]

I also will check out the gas venting when it does it. So if there is alot of pressure, it could possibly be that solenoid... Ill look at that and the flooring method probably tonight if she does it.
I may sound dumb when I say this, but since i've owned the SHO i've never done a 60k tuneup... to be more honest, I am googling that as we speak to see whats involved in it...

 

[jayro]

The crank sensor is a little involved. You have to pull the crank pulley and sprocket to get at it. Not super complicated depending on your experience working on a sho.

Autozone may not be able to pull your codes due to the age of the car. Last time I was there they did not have a store use scanner for our ECU. You can pull them yourself with a paperclip. If you use the search function it should pull up instructions for you.

Thanks for the compliment (If you were talking about my pic).

 

[Plasticmatt477]

I have some experience working on SHO's, but most of my mechanical experience is on camaros, buicks, and luminas (cars i've owner prior to the SHO). I basically just fixed problems as they came and with the camaro, they came in quantity lol. I know I could change the sensor with a little patience and guidance.

When you say search function, you are referring to in the forum? I looked it up on google and youtube and it looks like your talking about bridging the diagnostics unit and the check engine will flash the codes correct? If so, i'll search the forum and find the instructions and get codes... I am very impressed at how much everyone in here knows about these cars and am learning alot already!

Yes I was talking about your pic, no problem man I call em like I see em haha.

 

[rbruso]

I also will check out the gas venting when it does it. So if there is alot of pressure, it could possibly be that solenoid... Ill look at that and the flooring method probably tonight if she does it.
I may sound dumb when I say this, but since i've owned the SHO i've never done a 60k tuneup... to be more honest, I am googling that as we speak to see whats involved in it...

Actually, if you have excess pressure it's probably the little orifice in the vent line. From the throttle body follow the little vacuum line down past the coil pack. It will end in a funky cylinder with two vacuum lines and an electrical connector. Pull apart any junctions or tees between this line and the hard plastic line that runs under the radiator and make sure none of them are clogged. On the '89 the orifice is in an inline junction, but on others it has been in a tee connector. Just clean it out without enlarging the hole.

If (like mine) all the unions and tees are clear and free flowing it's likely a stuck solenoid.

As for the 60K, read through this site: http://www.shophoenixproject.com/maint.htm

The 60K links are at the bottom.

 

[Plasticmatt477]

Well, I think my whole day tomorrow is full now haha. Thanks to everyone for all the very detailed and helpful suggestions and tips!!! This will give me a great start on the issue & a 60k tune-up will follow that immediately (after I read up on it of course)... The Phoenix Project website is something i'm going to read inside out! looks like great info! Also i'll post back either way after I try some of the steps you guys have given me.

Matt

 

[Plasticmatt477]

Well, went out and started my SHO... I forgot when it was sitting that I changed the manual tranny fluid and oil, so when it started smoking (bc i'm messy) I was worried, but that cleared up. I took her for a nice ride to get the grease, oil, fluids running again. Ran beautifully. Parked it out front and let it idle and out of nowhere it just died... one min idling fine and the next dead. Started right back up then and idled fine again. So my problem is definitely intermittent.

Just wanted to keep u guys updated... i'll have more info tomorrow when I do the diagnostics and others, but wanted to get the bat charged and everything running tonight. Also, there was basically no pressure when I popped the gas cap to get more fuel (always premium... didn't know if you all used premium).

Matt

 

[jayro]

Doing a full 60K will eliminate alot of the possible issues. After that it would be easier to trouble shoot.

 

[Plasticmatt477]

OK, I got the codes... it was my first time, so I did it twice and this is what I got... Its a GEN 2, so 3 digit codes is what the Phoenix Project said.
556
556
1
1
765
435
561
765
435
56
now, I think the 2nd "1" was the start of the next line of code, but I wanted to run it by you guys 1st before I looked into the code meanings...

Matt

 

[Plasticmatt477]

sorry if that was confusing, but I posted the actual results and I think that the first 1 was a separator marking and the second 1 could possibly be part of the next line of code (which would move them all back). so if i'm correct...
556 (O,M) Fuel pump relay primary circuit fault - Power / Fuel Pump Circuits
556
1
176 (M) Oxygen sensor not switching - system is or was lean Left or Front HO22SSS - Fuel control
543 (O) Fuel pump monitor circuit shows no power - Power / Fuel Pump Circuits
(M) (Service 556 code first if present) Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits
556 (O,M) Fuel pump relay primary circuit fault - Power / Fuel Pump Circuits
176
543
556
would end up being the real codes... if i'm following this correctly.

Thanks and sorry for confusion,
Matt

 

[Plasticmatt477]

sorry to bother you guys, but I really wanna see if you have any thoughts on these codes...? thanks!

Matt

 

[General Geoff]

With that many codes, I'd check your ground connections first and foremost.

 

[Plasticmatt477]

ok, grounds to the fuel pump?

 

[Plasticmatt477]

I went to get out of the SHO and I think i've found a major electrical problem! With the headlights OFF and the car off, it beeps *BING BING BING* like when the headlights are ON... I went to grab the steering wheel and when I pull on the wheel, the BINGS stops... let go and theyre back! Looks like i'm droppin the column tomorrow. Not too sure what to look for, but hopefully its in plain sight. (this would explain my Bat draining on its own)

Matt

 

[Plasticmatt477]

UPDATE on Issues

Took the column apart and found a loose wire next to the ignition that was grounding itself. The car now runs fine, doesn't act up and weirdly enough seems ok now... I don't think the problem is solved, but i'm going to be starting the 60k now.

Thanks for all the help,
Matt

 

[rbruso]

Intermittent shorts can cause the weirdest problems, though I think there's still something else going on. A wire in the column shouldn't cause the temperature-related problems you originally described.

Was the insulation worn through like the wire was moving around? Hopefully that's the only intermittent short lurking in the column.