96 f150 w/ 200k miles. 302. usually runs perfectly. has thrown a p0401 and a p0443 code. had autozone reset just to be sure. codes came back in about 20 miles.

this has begun to happen more frequently - going down the road and the truck just dies - like it lost all electrical power or ran out of gas. Coast to the side of the road. Usually, can wait 10-20 minutes and it will crank on the first hit. Two nights ago, drove it and parked it. came back out - nada. waited 10-20 minutes. nothing. before two nights ago, sometimes you could drive the truck 200 miles and not have a problem.

what i've done so far - replaced fuel filter, replaced coil pack, replaced starter solenoid, replaced starter. had battery checked and made sure cables are tight. took the EGR off and cleaned it - seems in good shape. no obvious vacuum leaks. Checked the fuel valve under the hood - good pressure and gas sprayed on the guy that checked it.

yes, I know I probably didnt have to replace some or most of those parts, but it was a cheap investment in a 200K+ engine that never gives me a dime of problem.

what i have not done. a prof mechanic friend said he has seen the crank shaft sensor (I believe that is what he said) cause a truck to die like that. Reading some other posts, I saw a good bit about a DP?? or DF??? sensor I might need to check. havent changed the distributor, spark wires or coil wire. havent changed the EGR since it seemed to work fine.

i'm not the best mechanical mind in the world, but i love to learn to fix stuff. if you can explain it, I can go try it.

Any help much appreciated...Kevin

 

the check engine light has been on for years and the truck ran perfectly. I doubt either code has anything to do with this stalling development...but i did want to mention it.

 

My 05 did the same thing last year. It died and I pulled over let it set and then started back up. It was very spiratic though.

Ended up being the throttle body. Don't know how to check if your issue is the TB..??

Good luck man

 

The 401 code says that you don't have enough gases being recirculated and most likely the EGR will need a cleaning if it's never been done. The 443 code says that the EVAP system is not working correctly. Neither on your model truck will cause the issue you are having by the engine just turning off like you turned off the key. Most likely culprit is the spark control module on the side of the distributor. When these get hot, they just stop sending signal and the PCM thinks the engine has stopped so it does nothing. Just like turning the key off.
Here's the part:

 

i found it - drivers side under hood just behind fender well. is there a way to test it - at home or maybe at an autozone?

 

took ignition control mod and had it tested. series of 5 tests. all good. what next?

 

Check running fuel pressure, document/ needle should be steady. Engine running, tap relay lightly while monitoring pressure. Also, feel relay for heat. They get hot when bad.

When it won't start, check primed pressure. When it won't start, turn key to run and listen for pump prime. You should hear this per key cycle.

This also could be a regulator issue, -so when checking fuel system, thoroughly check regulator operation.

Here's a chart, -some of these operations you can do. -

 

there is a vacuum line (white) the runs to a silver canister with a hinged arm coming out of the bottom of it. arm connected to a shaft that goes down into heater/air assembly? canister located passenger firewall in corner. one online diagram looks like it is outside recirc vacuum pump - hard to tell. but vacuum line was totally corroded and had a big gaping hole in it. I cut the bad part out, pulled it back, reused the boot, and reconnected it. probably has nothing to do with engine stalls, but I did fix "something".

am also changing the plugs and wires. wires are the factory jobs - 200K+ miles probably time to change anyway.

dont have a tester for the fuel pressure, but will see what i can find. i'm also going to take the ignition control mod back to autozone to retest. several threads said they can test fine when cool then test bad when warm. we'll hit it with a hair dryer and see if it changes.

 

Update - found one other issue. the EGR pipe had a leak. plugged it. Also replaced all the plugs and wires. Noticeable difference.

Question - does the heat sink on the spark control (ignition control) module ground it to the body? If so, I probably fixed another issue - the back of heat sink was covered in dirt and crud. wire brushed it and its contact point on firewall.

Reset the codes - drove it about 20-30 miles. No check engine lights. Power is much better. Crossing fingers...