91 Thunderbird, refusing to run.

Topic: 91 Thunderbird, refusing to run. (Read 1179 times) previous topic - next topic

91 Thunderbird, refusing to run.

August 23, 2007, 02:50:35 PM

So, I'm back. The 87 TurboCoupe's been sold, and the new toy is giving me grief already. The car in question is my father's 1991 Thunderbird with the 3.8 multi point motor (Yes, the cursed one which runs ridiculously warm and has the grill opening sufficient for a Pinto). Originally the car came from a friend who thought the block was cracked, turns out the passenger head gasket was mangled on the water jacket, and coolant found it's way into the cylinder. After a complete top end overhaul, the car's been running great for about 3 years now, only having little issues now and again (faulty IAC, TFI module, etc.)

So out of nowhere the thing decides today it's going to crank, start, but sputter and shut off immediately. If the throttle is held, it will run, albeit py. It pops and cracks as if it's running rich (and believe me it is) but otherwise it'll run until the throttle's released.

I've checked the coil, it's fine, Fuel pressure at the rail is 40 psi, pumps runs good 'n loud (and yes, I checked to make sure there was gas in it... 3/4 tank XD), and I don't have any codes (other than it complaining the motor wasn't warm enough :D ) I'm honestly stumped, and rather than take it to the dealer I'd like to know if there's anything else I could test before 'fessing up some serious dough. Thanks!

91 Thunderbird, refusing to run.

Reply #1 – August 23, 2007, 02:59:48 PM

UH....codes?

91 Thunderbird, refusing to run.

Reply #2 – August 23, 2007, 03:03:40 PM

There are none, except for the normal 111, and then I also got:

21 (Engine Coolant Temperature (ECT) sensor out of range)
54 (Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal high)
57 Intermittent in Park/Neutral/ Switch or Neutral Pressure switch circuit
337 EGR feedback signal is/was was high

I couldn't warm up the engine, since it won't stay running long enough.

91 Thunderbird, refusing to run.

Reply #3 – August 23, 2007, 03:16:21 PM

Quote from: TurboChicken;171486

21 (Engine Coolant Temperature (ECT) sensor out of range)

if its running rich, that sensor probably see's that its REALLY cold outside, and fattens up the fuel mixture (so your right, it probably is running to rich). also at that point, when u give it gas, all your really doing is giving the engine more air, and a more even a/f mixture whhich is why it runs a little better. probably really high revs, but better. i'd work on fixing that first. basically your running in open circuit all the time. its like riding a motorcycle with the choke on the entire time.

91 Thunderbird, refusing to run.

Reply #4 – August 23, 2007, 03:24:26 PM

But would that be enough to keep it from running at all? It literally sounds like I'm missing cylinders right now, that's how bad it runs. But I suppose I'll look into the ECT sensor a bit more, it's better than nothing :hick:

91 Thunderbird, refusing to run.

Reply #5 – August 23, 2007, 03:37:13 PM

idk, ive seen some bad ones before. the cylinder wont fire correctly if theres too much fuel in there. what color is your exhaust? is pretty black? and there may be other reasons its not running correctly, but thast sounds like the big reason to me.

btw, if its running then dies, and u go to restart it right away, does it run? or do u need to wait a little while before it will restart?

91 Thunderbird, refusing to run.

Reply #6 – August 23, 2007, 03:46:06 PM

Alright, I just got back from pulling the cap for laughs... and this is what I found (images attached)

My Dist. rotor is FRIED... what would cause that? It was perfect yesterday. Also, the cap's coil point is also charred and missing (now my dist. is filled with giblets...great...)

I'm heading off to grab a new cap and rotor, but I hope it doesn't do this again ><

91 Thunderbird, refusing to run.

Reply #7 – August 23, 2007, 03:54:42 PM

haha, did i say ECT? cus i ment to say fried cap and rotor! tom-A-to tom-ah-to right? lol. idk what would cause that. except for maybe just getting just old or carbon tracking.

91 Thunderbird, refusing to run.

Reply #8 – August 23, 2007, 04:11:46 PM

Might be nothing - that cap and rotor need fixing first but

Code 57: I know that Park/Neutral switch has to be working for it to start but does it kick out of the circuit once the key is released or stay in?

91 Thunderbird, refusing to run.

Reply #9 – August 23, 2007, 04:38:57 PM

Nah, when I release the key it stays running... or at least it attempts to. Just got back, getting ready to throw the cap on and start it up *crosses fingers* I've never had a neutral switch issue before, so I'm not sure if maybe that was just a stored code or not... I cleared them anyway, so if it returns I'll worry with it then

Here goes nothing! :hick:

**EDIT**

So it runs, smoother than this morning, and hopefully the cause was carbon build up leading to the detonation of the rotor. Thanks all!

91 Thunderbird, refusing to run.

Reply #10 – August 23, 2007, 06:02:00 PM

the ect,iat and possibly even the egr are because the car is not warmed up and therefore it is not seeing the signals from these sensors,it is normal until operating temp is reached,glad to hear you fixed it.