You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!
I have been searching the forums here but cant find specific info to my year truck or problem. I just changed both in tank pumps and filter because they died and truck ran great for about 6 miles, then promptly died.
I have heard suggestions from the coil to the IAC, MAP, AIV, FP Regulator, FP and adjacent relays, TPS and other sensors. The ignition switch (on the middle of the steering column) has been replaced (a suggestion) but no difference.
We just purchased a new coil, ignition control module and distributor pickup assembly to try. I will see if the existing coil has power by pulling and testing with another spark plug JIC. In lieu of that being OK, What is the likely culprit?
After cranking, I depressed the Schrader valve on the fuel rail and fuel did bubble out but didn't "spray" at me.
I also have not been able to locate the OBD-I test fittings but will look again. I only have an OBD-II tester so I guess I should get another. I also disconnected the battery ground for several minutes JIC to clear the ECU memory.
Oh...I forgot some more info FWIW. The truck is a 95 F150 4x4 XLT extended cab with dual tanks and 230K orig. miles and I am the original owner. The dist. cap, rotor, wires and plugs were changed about 40K ago.
get a fuel pressure gauge. so you know if it is building pressure, and maintaining the correct pressure.
I've had pumps that ran good and built up pressure at idle but when you gave it gas it would drop about 5 psi and not build back up, at all.
then it would drop again if you hit the gas again, it would do this until it dropped to no pressure and died..
It happened directly after your repair, so there's a 99% chance that something isn't connected correctly or maybe you got a faulty part. I know it sucks, but you need to verify your repair before you start looking at anything else.
Check for power to the Interia switch. May have got tripped and shutting down pumps. If you have power there, try resetting it. Tap on it with wrench and see if the button springs up, then push it back in to reset. Once its set should have power coming in and going out to the pumps.
The initial symptom that prompted the fuel pump replacement was that the front pump became very loud. It then stopped making any sound when the key was turned on. Additionally, if you switched between the tanks while driving (from rear to front), the engine would want to die (no fuel...duh).
The truck ran fine on the rear so I figured I would just have to get a front pump. Then the truck started dying indiscriminately on the rear pump, sometimes after a lot of driving, sometimes after only a few minutes and then finally died altogether.
The tanks now have fresh fuel with Lucas stabilizer. The new pumps come on when the key is turned but I am not sure how to verify their output once installed. I will see about getting a FP gauge to test cranking pressure and if it holds.
Where do I find this inertia switch and what else could be causing this issue? I don't want to have to pull the distributor if at all possible but if the culprit is the dist. pickup, I am OK doing that.
Have you thought about a Fuel Pressure Regulator? If the rack pressure is not up to snuff the injectors will stream fuel into the port instead of fogging it in. This will cause problems in ignition and there are plenty of these regulators that will cause the fuel to circulate through the rack and return right back to the tank.
The regulator allows a constant pressure to be supplied to all the injectors in the system and it does it by closing off the path of return to the tank until it reaches the proper pressure. It could be that simple.
I will look into the regulator possibility as well as the inertia switch soon. I am presently recovering from back surgery so no excessive movement or work from me as I am officially a temporary couch potato.
An obd I code reader is almost not worth the money. I've made a jumper out of a short wire and two male spade connectors and attatched it to the harness at the test plug. Place jumper, key on, copy flashes, decode . Of course a reader might be a wee bit faster.
How well did the connectors go back on the tanks?
Do you think you crimped the new wires on really well?
The fuel pressure testor is almost a must. I was puttin' out about 30 psi and thought I had full pressure. It's worth the $$ to get a testor that will do most makes.
Chase the fire / chase the spark / chase the fuel / check the timeing
1) what codes are thrown?
2)what pressure do you have on the fuel rail?
3)Next time chase the spark before spendin' 150$ on ignition parts (I've spent at least that on parts so far myself But you shouldn't have to worry about them now. You've already solved these next steps.
1)fire at the plugs
2)Blue fire at the plugs?
3)fire at the dist? consistent ?
4)are your primary and secondary coil resistances within tolerance?
4) are the plugs wet? are they fouled?
5) are you in time?
I have a crank no start issue too. One of my problems was a little bit of rust in the bottom of the distributor. (My opinion) It was causing the injectors to fire at odd times. Once I replaced the hall sensor and cleaned the distributor I now get detonation in the cylinders. But I have other troubles now... If you would, please take a look at my thread and see if anything comes to mind.
Thanks for the info. I am sidelined with the back surgery recovery but will get son to start testing all mentioned. I will swing by HF and see if they have the gauges and testers cheap. It is either that or I trailer it to a local shop for probably $85 to test and determine the issue with the fix to come later.
There are so many things I have to do and I am stuck on the couch.