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Tried everything possible on my 4.0 ohv Need help please!


New Member
June 17, 2017
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1998 ford ranger exlt 4wd
Hello! I have a 1998 4.0ohv 4wd. Recently I got the p1309 code and also the p0171,p074 bank 1 and 2 lean codes. I proceed to change out the Cam Position Sensor and syncro. I did them both correctly exactly by the book. Made sure to put the engine at top dead center ect. I reset the computer ( left battery unhooked for few hours ) and started her right up. It began to relearn itself but started running rough and sputtery. I maybe thought it could be the
TPS ( throttle position sensor )
MAF ( Mass air flow )
IAC ( idle air control )
and air temp gauge.

I ordered a new MAF and TPS since i found a good deal on amazon. I clean the temp gauge and IAC. After another reset it developed this problem.

from 0mph full throttle no acceleration at all. 0. half throttle was quick and fast and sounded healthy. I proceeded to do some research on the fourms and found a issue could be ground wires and PCM ( power control module ,the ecu/computer ) I checked all my grounds and even took off my coil pack and cleaned the grounds under the coil pack and threw it back on. I even checked the fuel filter and got sprayed right in the ear -_- even though i relived the pressure! Right now its doing another computer reset.

My question to you dear kind folks is this. What the hell could it possibility be!?

ive checked spark plugs, cleaned air filter, checked fuel filter, checked all vacuum lines, brand new MAF,TPS, cleaned IAC and temp gauge. I need help please! Im lost and dont know what to do. thank you all so much!

Not sure about your p1309 code but I suspect you're on the right track investigating your cam sensor and synchronizer.

I can tell you from experience that the lean codes are a pain. How did you check your spark plugs? How are the wires? Hows the coil pack? What brands of parts are your using? I know the Ford EDIS is sensitive to non-Ford parts.

Have you checked the fuel pressure using a gauge via the test port on the rail? I'd do that first.

Was it running OK before the cam syncro change?
Are you sure it was at TDC on the compression stroke when changing the syncro?

I remember something about the PCM going into open loop at WOT...?
Maybe that gives a clue. I'd check the O2 sensor wiring or anything that
may have been disconnected (on purpose or by accident) during the
syncro work.