Help with Bronco "Flame out".

[Conejoracer]

Hi, I'm having some troubles with my Bronco, and could use some help. I've searched online already, but cannot figure this one out. I have a 92 Bronco with a 5.8 and E4OD. The odo shows 270K miles. The engine has new plugs, wires, cap, rotor, water pump, and fuel filter. It runs great most of the time (98%) but has an occasional flame out on start, or while driving. This usually only occurs when the truck is cold, and the outside temp is cold/cool. When it shuts off, it can take a little while to restart, and there is often smoke coming from the exhaust as if it were flooded (smells like it).
I ran the engine off diagnostic twice, once receiving a code 33 (EGR opening not detected), then a code 111 (system pass). With the engine running test (with the engine warm), I received code 116 (engine temp higher/lower than expected), code 538 (insufficient RPM change during KOER test, Invalid cylinder balance due to throttle movement during test), and code 632 (torque converter solenoid circuit did not change status during the test). I did not turn the OD on/off during the KEOR test, maybe explaining code 632. As far as additional info, the Tachometer is off, always reading high, and the engine temperature gauge sometimes works, sometimes not.
So does anyone have an idea of where I should go from here?

[philofab]

I would start looking at the distributor pickup, external TFS module, and coolant sensor.

Check the distributor shaft for side to side play too.

[johncharlesb]

Have you checked anything while the engine won't start? I would check the coil for hot power and spark the next time this event occurs. If the coil is powered and you dont have spark, start back checking the ignition as Philo suggests. If the coil is unpowered, check its circuit. If the spark checks out and it does not start, move on to the fuel system.

Make sure your engine/body grounds are good as in HTO's "Problem" post. That will definitely do whacky stuff.

[hobbyturnedobsession]

I had a problem with my grounds and it worked but I never had it flame out like youre talking. John's idea of the grounds to check is a great idea, and cheap. I'd start there then mess around with things that cost money. I know that I had a problem with my idle and it was the map sensor. Thatll do some trippy stuff too. Hows your timing? Seems kind of wierd. Mine did that when we first started it after the motor build but that was because the distributor was 180 out.

[BajaF250]

I would most highly recommend you check or just replace your coolant temp sensor. If it's bad, it'll tell the computer that it's cool and richen up the air fuel mixture. If your truck stalls, try starting it with the fuel pedal fully depressed to open the butterfly. If it starts, you may have isolated the problem.

[Conejoracer]

I did forget to mention that the only way it restarts is with the throttle fully depressed. I have fully checked the grounds, I had that problem when I relocated the battery. All grounds are substantial and intact, so I do not think that is it. I'm going to throw a coolant sensor in it tomorrow and see what happens.
The distributor seems fine, timing is right on, and all the usual suspect parts appear to be working. Usually I am stuck on the road blocking traffic, so I have not had the chance to check for spark when it is acting up. I'll keep that in mind though, thanks!

[philofab]

Pedal to the floor indicates a rich condition. It may be a good idea to look into your MAP sensor's vacuum line too.

[Conejoracer]

Today I replaced the coolant temperature sensor for the gauge, and it works now. I then replaced the ECT sensor for the computer, and took the Bronco out for a spin on a pretty cool day here in Socal. The Bronco seemed to run much better, I noticed the engine ran smoother and felt a bit more powerful. I'll have to give it a few days before I will feel its fixed, but so far, so good!
Thanks for all the help!

[Polarcub]

I did forget to mention that the only way it restarts is with the throttle fully depressed. I have fully checked the grounds, I had that problem when I relocated the battery. All grounds are substantial and intact, so I do not think that is it. I'm going to throw a coolant sensor in it tomorrow and see what happens.
The distributor seems fine, timing is right on, and all the usual suspect parts appear to be working. Usually I am stuck on the road blocking traffic, so I have not had the chance to check for spark when it is acting up. I'll keep that in mind though, thanks!

I had a similiar problem with my 83 years ago and it turned out ot be a ground off of the fuel system. I dont remeber exactly where it was located other than it grounded to the block and that the wire had actually been broke at the connector. It was a real PITA and took me several weeks of chasing down to figure out.

[Conejoracer]

Okay, maybe a new problem here, or not.....

Now the Bronco will not start. Spark is good, distributor and coil are good. The Fuel pump runs continuously with the key on. I checked the relays, they are good. While cranking, the smell of fuel is strong, and if it comes close to starting it smokes like crazy. Is this a ECM issue? I do not have a gauge to check the fuel pressure, but could it be bad too? My reasoning (please correct me here), with the fuel pump running it should start and stay running. If the FPR is bad as well, it is getting too much fuel and flooding? I'm starting to think that this is an intermittent problem that has been the issue all along. Any thoughts?

[Conejoracer]

Okay just barely got it started...... It ran very rough, smoked profusely, would not idle, had the check engine light on and died. It would not restart, Its VERY much flooded.

[philofab]

Okay just barely got it started...... It ran very rough, smoked profusely, would not idle, had the check engine light on and died. It would not restart, Its VERY much flooded.

Check that the map sensor is hooked to vacuum without any leaks.

[philofab]

Fuel pressure regulator can be checked by pulling the vacuum line and checking for fuel.

[Conejoracer]

The map sensor looks okay, no vacuum leaks. I pulled the vacuum line off of the FPR, dry there. If the the fuel pump continues to run with the key on, engine off, would that flood the engine? Maybe a stuck injector? If the FPR is bad, would the fuel pump keep cycling fuel through it continuously?

[philofab]

The map sensor looks okay, no vacuum leaks. I pulled the vacuum line off of the FPR, dry there. If the the fuel pump continues to run with the key on, engine off, would that flood the engine? Maybe a stuck injector? If the FPR is bad, would the fuel pump keep cycling fuel through it continuously?

The fuel pump is timed. If it's staying on longer than 5 seconds or so with the engine not running, ignition on, there is an issue with the ECM FP wiring, or FP relay.

[Conejoracer]

I pulled the ECM and found two of the resistors have leaked out corroding the board. I guess I need a new ECM! My ECM is the California F2TF-DA, any opinions on where to find the best replacement?

[hobbyturnedobsession]

autopartswarehouse.com has them.

[philofab]

I pulled the ECM and found two of the resistors have leaked out corroding the board. I guess I need a new ECM! My ECM is the California F2TF-DA, any opinions on where to find the best replacement?

JY or eBay. The are probably capacitors if they are leaking something. Resistors are normally burnt if visibility damaged.

[Conejoracer]

Okay, two capacitors were leaking on the ECM. After calling around, nobody had one in stock, and they were not cheap. I decided to give it a go at fixing it. First attempt; a trip to Radio Shack, a bit of soldering, and she fired right up! Then pop and smoke. Sheesh. So I pull the ECM (only partially reinstalled in case of this happening), and a 47uF capacitor I installed had exploded. It turns out I had accidentally bought a polarized capacitor, and it was installed backwards. Back to Radio Shack to get a NON polarized 47uF. I soldered it in and success again! I'm a real hack when it comes to electronics, and I worry that my soldering job may not hold, but other than that, fixing the ECM for less than $5 is so much better than spending $162.99 for the cheapest ECM I could find locally.
If anyone has a working F2TF-DA ECM laying around, I'd love to buy it for a spare!
Thanks for all the help, you guys are great.

[SteveG]

Nice job!