Ok, this one has me stumped. Got this truck from my boss who couldnt figure out what was wrong with it. it seemed like it wasnt getting fuel. to make a long story short, i replaced the high pressure pump on the rail, low pressure pump in tank sounds ok, replaced fuel pressure regulator and fuel filter too. it will run at an idle if i spray gas in the throttlebody to start it but the second i go to give it gas it bogs out and half the time stalls out. inertia swith is button is not out and it smokes which he said it never did previously. i put new plugs in it, tried a new map sensor, checked vaccum to map sensor, tried adjusting timing, ran fuel injector cleaner through it. i have no idea what it could be? any idea other than a stick of dynamite?
Update:Well, found the problem. noticed smoke from the back of the motor, realized there is a aspirator tube that runs from the egr to the back of the intake manifold. it is completley disconnected from the manifold, the tube rotted off flush with the manifold. Any ideas on what its called or how i can fix the problem? Thanks
Answers & Comments
Verified answer
throttle position sensor? plugged exhaust? bad pcm or wiring to pcm?
clogged injectors?
The first thing I would have tried would have been the TPS (throttle position sensor) mounted to the side of the throttle body. As the pedal is pressed, it rotates, sending a signal to the ECM that you need gas. You can test it by looking for voltage from about .9v up to 1 volt at wide open throttle, or just buy a new one and try it. To test it you'll need to find the hot wire and ground wire. There's a third wire that should show 5 volts, that is the power supply to the sensor.
How many miles are on the truck? Any way for you to get the truck somewhere to have a diagnostics check done to it?
To ken k, for an experienced auto mechanic you're not very savvy on these trucks. 1988 BRONCOS DON'T HAVE A MASS AIR FLOW METER
Geez.
have a 1988 ford bonco 302 getting fuel to fuel rails but to throttle body .....
only other thing i can think of is maybe a pinched ecm wire or the module is getting weak in the distributor
Do you have fuel pressure, blocked exhaust, timing too slow,
it is the air flow meter-available at any real parts store