I recently picked up a 2001 Ford Ranger with a 3 liter V6 engine. Since I bought it it’s been idling a bit rough and the problem is getting steadily worse. Two weekends ago I replaced the spark plugs and wires which helped some, but still not great. I took the car in to my regular mechanic who kept it for a week, checked compression, fuel pressure and who knows what else, but could not find any problems except codes for engine misfires.
I had to use my truck for work a few days this week so I picked it back up from the mechanic. Today just for fun I went to AutoZone and had them check for codes, it came up with engine misfires and a P1400 which points to the EGR pressure sensor. Replacing that helped some but it’s still not great. When replacing the sensor I noticed a lot of what looked like electrical corrosion inside the vacuum hoses - that can’t be normal.
Replacing the sensor helped, it’s not stalling out on me any longer. However, it’s still rough at idle and doesn’t have much acceleration from a stop or getting on the freeway. If I’m sitting in neutral and rev the engine it bogs down around 3000 RPM and won’t go any higher (maybe, maybe not related). When driving on the freeway it will get up to 3500 or 4000 if I’m accelerating hard.
I’m also hearing a creaking/grinding sound from the front-right when I try to accelerate, but I’m thinking that’s more likely the suspension. I can’t duplicate that sound sitting still, it’s only when moving.
Recently the oil pressure gauge started going wacky. When idling at a stoplight or in the driveway (cold or hot, makes no difference) the pressure gauge goes berserk and swings wildly back and forth between low and high. Sometimes I can even hear it clacking against the stopper. If I put it in neutral, the pressure gauge goes back to normal. Once I start moving, it goes back to normal. At this point I don’t know if the oil pressure is actually doing that or if there’s something wrong with the sensor or gauge and I don’t know how to test that. Again, maybe or maybe not related.
What’s the next step with this thing? It’s no longer putting out any codes, but it’s still not running like I want it to. The oil pressure gauge concerns me a bit, but if it’s only a sensor then no big deal. Suggestions?