Lose power at mid-high rmps and now won't start!
My brother has a 2000 A/T 4 cylinder and has had some problems lately. I just picked my first tool set Nov 2009 and only have a few months experience. My brother is very mechanically inclined, but still no professional.
First when he was driving to work a couple weeks ago he heard his engine start making knocking noises, and when he stopped to look under the hood there was engine oil all over the engine bay and there was no oil left in the engine. He figured it was destroyed because it was running like crap so he bought an engine and swapped it out. It started fine and drove fine for a few days, but then started to lose power when he got to around 3-4k rpms. The power would surge down and come back up. It did this for about a week and then died completely and wouldn’t start up anymore. That’s where we are. Unfortunately neither of us are pro mechanics and all I’ve ever worked on is my 97 maxima, so my knowledge of American cars is kind of limited. It sounded like maybe fuel pump or throttle issue to me at first but he said he pulled the plugs and tested for spark and got no spark on any cylinder. Coil packs never all go at once so I am now sort of leaning toward CAM sensor or Crank sensor. On my Maxima, a bad CAM sensor would cause no spark, but a bad CRANK sensor would not. BTW the crankshaft is turning fine, so it’s obviously not a bad starter.
Questions:
1-On Rangers, anyone know if I can test the coil packs and spark plugs with a multimeter? If so, how? What voltage am I looking for? AC or DC?
2-Anyone know the specified allowed resistance on the crank and cam sensors? Am I off base thinking these 2 may be the culprit?
3-I will be pulling codes tonight with OBDii but on my Maxima, CAM and CRANK sensors often don’t throw codes even when they’re totally dead. Can I expect a code if his sensors are dead?
Thank you very much for any help you can provide.
Daniel
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