Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Ey guys i need some help. Dodge dakota 1994. It has fuel rails and individual fuel injectors in it with cam and crank sensor. Customer has tune up in it(cap, rotor, wires and coil). This is speed density engine no mass airfolw sensor. Cust. Has eliminated the catalytic converter only straight pipe now. The fuel preasure is 43psi at idle (specs is 35-45psi) and when rises rpm fuel pressure never drops and stays the same at 43psi. The problem is misfire as Rises the RPM around 100-1200 rpm and once u pass that it starts running fine. Spark plugs have been replace too by the way. I check the injectors waveform (snap throttle test) and waveform is good all the way the pintle hamps are there from 1-6 injectors. I checked crank and cam signal and map signal and no drop out. By the way there is not have any codes in the memory. Checked all plug wirings making sure they are in their right location from the cap to the plugs and they are right(thought cust. makes mistake during his tune up). I was thinking exhaust being partially plug as vacuum gauge is dropping as i rises the rpm. however, i noticed my shorterm fuel trim goes very negative(-24) during misfire period meaning the condition of the engine is in rich mode but again this is an speed density engine(map). And also fuel pressure never change and stay 43psi whic is within specs. Don't know what is my next move next yet and it has been frustrating for me working on this vehicle. I need help guys. Thanks
It involves checking the distributor rotor for play, and replacing the distributor drive gear/bushing if too much is found. There's also a nice synchronization procedure in that same PDF for reindexing the distributor after repairs.
Speaking of, did the customer ever try to put his own distributor in it? An incorrectly indexed distributor can cause issues like this, too.
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