I purchased a 92 dodge 150series pick up with a 318 fuel injected engine 4wd 176000 miles on it. Not a bad truck it runs strong and is mechanically sound EXCEPT for the strange missing sensation when on the highway. The dude I bought it from said he thought it might be the map sensor. O.K. I put a map sensor on [ which I purchased from chrysler/dodge] and it didn't make one bit of difference. I ALSO GAVE IT A COMPLETE TUNE UP plugs,wires cap rotor,air filter, fuel filter oil change , Still there ,that strange bucking engine miss kinda drive you freakin nuts problem.I had no fault codes with a scanner. I CHANGED THE CRANKSHAFT SENSOR to no avail.I changed the ignition coil nodda I changed the pick up in the distributer nodda I ran lucas injector cleaner through it nodda The dude I bought it from put a water pump on it about 5000 miles ago I sure hope there's no mechanical damage to the engine . It only does it at 55 mph and above .Especialy on long trip 65-70mph is worse. HELP?
2006-12-22 14:32:47 · 4 answers · asked by jo jo 3 in Cars & Transportation ➔ Car Makes ➔ Dodge
look down your throttle body in to your intake. if you have oil in there. then your belly pan gasket is blown. if I remember right this will cause missing sensation at highway speeds. its easy to check and costs nothing.
also want to replace your throttle positioning sensor as it will cause this also
might be a good idea to take your TB off and get some TB cleaner and clean your TB real good.
2006-12-23 02:26:00 · answer #1 · answered by Jecht 4 · 0⤊ 0⤋
Surging at speed can be difficult to pin down, especially when it's intermittent on newer FI vehicles. On older high-mileage vehicles, surging is often caused by bad O2 sensors (pre or post cat), plugged EGR or even a plugged catalytic converter. Also don't forget the fuel filter and electric fuel pump. Any and all can cause problems like this.
On older Mopars, ignition timing can vary when the distributor gear/bearings start wearing too, although this usually causes problems at idle and lower speeds.
Your ScanTool reading from the OBD plug may not catch minor problems as on many cars, the problem codes clear if they are resolved quickly. For example, if you have a misfire and it only happens twice, it may reset after you shut the car down and re-start as the computer may interpret an occasional misfire as "normal." Yes, it's frustrating.
I would recommend bringing a friend along next time. Bring your ScanTool and leave it plugged into the OBD port. Drive at 60 under normal conditions and keep checking the readout for anything unusual. Although normally you should only use a ScanTool while the vehicle is stopped, most will operate while the vehicle is being driven as well.
If that turns nothing up, I would start troubleshooting the fuel system first, beginning with the fuel filter and a fuel rail pressure check. Then EGR followed by the O2 sensors.
Get back with us if those don't pan out and we'll go from there...
2006-12-23 01:10:34 · answer #2 · answered by Anonymous · 1⤊ 1⤋
I had 318 before. It had an engine miss, tune ups and dealer couldn't fix. It had bad valves, it was new too. I am suspect of a camshaft problem on your truck, worn out from mileage. We use to call that a (floating cam). It hits certain rpms and it will float.
Seen it in 318 and 340 mopar. Luck
2006-12-23 05:03:05 · answer #3 · answered by AJ 4 · 2⤊ 0⤋
Now try something simple like the fuel pump pressure or fuel filter.
2006-12-23 01:07:24 · answer #4 · answered by eferrell01 7 · 0⤊ 0⤋