Hi ... was wondering if anybody could lend a hand. My truck won't start. Here's the details

91 F150 5.8l, EFI, Automatic, 4X4, dual tanks

Pre-existing conditions; its been very cold here lately. Check engine light has been coming on intermittintley for the last couple of months, but truck has been running great.
Lately, the engine speed would race once in a while, sometimes getting up to 2500 rpm. This would happen after driving a while, with the engine fully warmed up.

Now she won't start. The engine cranks, the fuel pump primes, but no ingnition.

Here's the codes
116, 122, 114, 172, 173, 327, 328, 634.

I used the Key-on Engine-off test, using a test light count the flashes method. Thoughts ?
thanks

 

Sorry about your troubles, however it may have something to do with something upstream from your throttle body. I installed an X 303 cam in my mustang and in cold weather when i would start it to charge the battery, it would surge. I found out later that my MAFS wasn't calibrated properly to accomidate this extra cam lift. Normally you can "tap" a MAFS when the vehicle is running and if the car slows or speeds up you know that the unit is faulty. Not starting up is another story. I guess I'm rambling and not answering your question, but do you know what those codes mean? If not I would call a reputable Ford dealer to find out and maybe you can pin point the issue. Hope this helps.
Keep on crankin' that Ford blue!!

 

OK ... I did some research, and this is what I came up for the codes;

116 Coolant Temp out of test range
122 Throttle Position sensor out of test range
114 Intake Air Temp out of self test range
172 Right HEGO lean
173 Right HEGO rich
327 EGR valve pressure transducer/position sensor below minimum voltage
328 EGR Valve position sensor below closed limit
634 Manual Lever Position not at expected position

ECT, TPS, IAT, EGR ... where do I start ???

 

Sounds like its time to take it to the shop.

I personally would probably disconnect the battery to reset the PCM for grins and see if anything changes when you hook the battery up again.

Call your local Priest and have him get ready for an exorcism on your engine.

 

Here is something you might look at... One of the codes was tps out of range..
If it has failed and giving wideopen throttle voltage in the idle position, the computer will go into flooded mode and cut off the fuel causing the motor not to start.
you might want to check the tps voltages and make sure it is .9V at the idle position.
I have seen this happen a few times.

 

Gonz,

It wouldn't hurt a thing to remove and reseat all the connectors on the electronic's (sensors, etc.) of that vehicle, the ecm module first (the bulls eye for this trouble shoot). With that thing throwing all those codes all over the board like that. Also look for good clean grounds off the engine to firewall/chassis. As always remove the ground from the battery when working on the electronic's unless of coarse the device needs power to test.

Good luck, let us hear back.

T-man

 

I tested the fuel pressure - was getting 25 psi during the start cycle. should be 40. I replaced the fuel filter, measured pressure and now getting around 42. Now she starts fine.

Sorry guys for putting you through my dumbness; i'll go back under my rock. thanks for all the suggestions.

 

Gonz,

Thanks for the info! A fuel filter with a 17 lb pressure drop can cause a engine to fail to start. One more fact to tuck away in our old noodle!

Thanks again-----keep on truckin

T-man

 

Thanks for posting the solution. It nice that you had some test equipment.