Hi ya'll. I've got a 1991 Ford F150 with the 4.9L I6 coupled to the Mazda 5 speed transmission. Recently, the truck has been really starting to mess up. First thing this morning, I went to start it and it wouldn't start. I realized that the fuel pump was continuing to run, instead of clicking off after the 3 seconds. After about 10 minutes of checking leads, the pump clicked off, and the truck fired right up. I got about 2 miles down the road when the truck began acting like it had a backwards rev limiter installed. Idle dropped from 1K to 600, and the highest it would rev was 1200, misfiring badly. The engine threw a Check Engine Light at me, but Autozone said they can't pull codes off of anything older than 96. Anyway, I pulled off to the side of the road and wiggled wires and such, but with no luck. I decided to limp it back home, and about half way there (1200 RPMs is bad for upshifting), it cleared up. This afternoon when I got off of work, I tried my hardest to replicate the symptoms, but to no avail. I unplugged vaccuum lines, the Manifold Pressure Sensor, TPS, EGR sensor, Coolant Sensor, then went to far as to spray all the electrical connections with water.

*Brand new Plugs/wires properly Gapped
*Fairly clean, though old Cap and Rotor. Little wear
*Fuel Pump installed in January to the tune of $800
*Battery, Alternator, Water Pump, Starter, Belt, Hoses, Fuel pump relay all replaced fairly recently. (Fuel Pump relay coil burned out)

The Idle was somewhat rough, and extremely low. At the 1200 RPMs, it sounded like only 3 cylinders were even attempting to fire.

I would really appreciate some help in diagnosing this problem.

 

you can pull the codes yourself using a paperclip and all parts places sell a code reader for between 20 and 50 bucks most autozones read codes for all vehicles not just the OBDII ones . Sounds like you might have some wires on wrong or your timing is off maybe even the computer

 

Once I experienced what I thought was a hell of an electrical short, the engine sounded like it was trying to run backwards. Turned out to be a newer dist cap, one of the nipples was litterally falling off. Mine is a '92 300 cu in. and has the TFI mudule on the drivers fenderwell. For laughs you should make sure its got good layer of silicone grease between that and the heat sink. Auto zone can check the module for free. That thing gets pretty hot in normal use. I carry all Ign. parts when in Mexico.

 

Autozone said they couldn't pull the codes because it was Pre-1996.

I thought about the ignition coil/module. I just replaced a power steering pump that had a bad leak. The fluid coated everything on that side, including that coil. It was this way for a long time before I finally got motivated enough to replace the pump. I honestly can't remember that module ever being replaced...

I haven't changed any wires recently, and with it only doing this once in a blue moon, I have my doubts about the timing being off. (If it was, it would do it constantly, right?) The computer is a different story, however. I have had my share of Electrical problems...

 

New Idea, after reading several posts... Could it be a fuel pressure regulator? If so, where the heck is it located on this year F150?

 

Welcome to FTE.

I would start off by seeing what codes you can pull first. Go to www.fordfuelinjection.com and click on Getting codes.

 

Advance auto checks codes for free too if engine light is on???

 

it's very easy to pull them yourself with a paperclip. You have to jump two leads turn the key on and push the clutch in, the CEL will then flash, record the flashes.

 

I read the article on the website about Ford EFI. I plan to pull some codes and report back asap. The only time I've had, I consumed by doing a well overdue oil change.

 

Alrighty guys, it took forever to get the time, but I finally pulled the codes. Without further Adu....

213 - SPOUT Circuit Open.
328 - EGR (EGRP/EVP/PFE/DPFE) circuit below minimum voltage

I also get the 522 Transmission not in Neutral/Park error while doing the KOEO. I had the Tranny in Neutral and the P-brake set, so I don't know why I got this code.

Any Help? I checked the SPOUT connector to the ICM, and it seemed solid. I've noticed that this problem only occurs when the Engine is cold.

 

Please? I know SOMEWHERE out there is a genius.

 

I'm no genius, seeing how I'm not in a much better boat than you you, but you might want to start with the simplest things. Like make sure that your connectors are clean.

 

well old buddy i have had the same problem on my 89 f 150 and every time it has been the same thing in side youre distrbutor is a electronic device that i cant remember the name of right now but it only will do this once in awhile after it gets hot i have had about 5 of these trucks and it is the only thing i have ever had problems with. but it is inside the distributor. when i remember what it is called i will post it.

 

You wouldn't be referring to that little capacitor would you? If not, then maybe something to do with the distributor advance, or the Tach system? As far as my connectors, they're all fairly clean. I've tried jiggling them and all sorts of stuff, but with no luck.


An idea just hit me though... Is it possible that this could be a symptom of crossfire? I might have a couple spark wires laying perpendicular right at the distributor...

 

Sparkplug wires SHOULD cross at right angles (perpendicular) when possible. It is parallel plug wires that can crossfire to each other. But crossfire is a very unlikely explanation for your symptoms.

Check all of your engine/chassis/battery ground wires. There is a post on the radiator support right in front of the battery -- should have 2 wires going into the harness and one to the battery ground post. Remove the nut and bolt, shine up the metal under the bolt, shine up the 3 wires, and reassemble.

Pull the ground wire off the battery and clean the battery post and the inside of the clamp. If it is a replacement bolt-on clamp, check the connections where the wires enter the clamp.

Check the ground wire connection to the fender at the left rear of the engine compartment.

Code 213 should only happen during the KOER test. It means that the computer is unable to change the ignition timing. The most obvious thing is maybe you left the SPOUT jump out of the harness the last time you checked the timing. Alternatively, your TFI module may have gone bad and is not obeying the ECM's commands to change the timing. A flaky TFI is also consistent with "firing on three cylinders and is intermittant". Check static timing, then install the spout jumper and check that the timing advances as RPM increases.

Code 328 means the EGR valve position sensor is bad or the EGR valve diaphragm is leaking, the vaccuum line is off, the valve is stuck closed, etc. Is this a KOER code or a KOEO? If KOEO, then the problem is likely the sensor or the wiring to it. If KOER, then the valve is the more likely suspect.