1994 E-150 5.0 RUNS BAD, BUT WHEN THE MAF SENSOR IS UNPLUGGED IT SMOOTHS OUT SOME.I HAVE REPLACED IT AND NO CHANGE

 

Runs bad,,, can you give a better description.. Was/had the CEL illuminated prior to any work done.. Any codes? Any vacuum leaks, EGR, EVAP, or possibly PCV to manifold supply.. Has the man vacuum been checked? Misfire/stumble/stall, rolling idle with excessive emmisions ect..Just poor idle, or off idle tomid range running concerns.. Better/worse performance out on the road?

 

94 e150 while driving it acts like the van is not getting fuel. then when the accelerator is depressed it will run fine for a little while then it does it again .i have replaced the fuel pump ,filter fuel pressure regulator,map sensor,ignition coil & gave it a major tune up,i also had the exhaust checked for a plugged convertor. The cel will come on for a brief time. Just replaced the MAF still runs better with in disconnected. THANKS FOR ANY ADVICE

 

Is the idle normally fine? or is that when you pull the MAF connector? Is the poor performance and drivability just in the mid range power? or over all the ranges?

Does the CEL come on during the flat throttle? then go off just after?Possibly a drop out in the TPS would cause the power loss and flat throttle as well as set the CEL but generally tend to idle ok,or have youmonitored the fuel pressureduring an event and see what/where the indicated pressure is if more in the higher ranges? If you could have anymemory code/s read on a CEL, it may help in some direction.. You can check for DTC's with the CEL as lamp flash DTC coding..