So i bought a 1995 maxima from a guy who claimed it overheated and head gaskets went out. Oil was a milk float, yes. I bought it for $300 with the anticipation of fixing it of course. I replaced water pump, timing belt, accessories and head gaskets. Put everything back together and it runs like timing is off,
So i bought a 1995 maxima from a guy who claimed it overheated and head gaskets went out. Oil was a milk float, yes. I bought it for $300 with the anticipation of fixing it of course. I replaced water pump, timing belt, accessories and head gaskets. Put everything back together and it runs like timing is off, shakes more than it should, little rough sounding, not smooth. Compression is good. Tested resistance of injectors, one was way out of spec (10-14ohms) at 70 ohms and thought that was it, still runs like crap. New plugs are black and wet, seems to be running very rich.
Current codes are for crank position sensor 0407 (reference) and knock sensor 0304.
help pleasecould a reference for crank sensor really cause it to run like this?
Yes. The P0407 code indicates a problem with the REF crank sensor mounted near the front engine crank pulley. Your engine has two crank sensors…the other POS crank sensor is by the bellhousing. The PCM needs signals from both to determine proper engine timing. Could be that the front crank sensor is not hooked up, bad sensor or wiring issues. If the PCM does not get a good signal from the sensor, it can go into limp mode with basic fuel trims that are too rich, reduced power, etc…
P0304 is a misfire code for #4 cylinder….check for bad plug, plug wire, bad injector, vacuum/manifold leaks, EGR issues, etc.. on #4.
Repair the crank sensor issue first and the 0304 code may go away. Clear the codes on the PCM and test drive after crank sensor issue is fixed…see if the P0304 comes back or not.
Running rich could be due to the crank sensor issue or a faulty coolant temp sensor (ECT) which may not trip a trouble code/CEL if voltage values are still within specs…just wrong for actual engine conditions…test the ECT if needed. That may also be part of the issue why it runs rough.
Yes, a Crank Position Sensor can cause the same symptoms as a timing problem. What is timing? It's firing the spark at the proper time in the cycle based on piston position. What does a crank angle sensor do? It tell the the engine the position of the crank shaft from which the engine computer calculates the piston position. . . .
So, poor data from the Crank angle sensor can actually cause a timing problem!
Your codes are a clear indication that you put the timing chain on wrong, you don't have a timing belt and you would have known that if you really did this job. The injectors on this engine are a known problem and they should all be replaced. What did you do to resolve the over heated heads?
Bad crank sensor can tell the computer that the engine is not running. On both my diesel pickups CPS failure let the computer tell itself, "Engine not running, don't bother charging the battery."
Who knows what your car's computer may be thinking, but it can't be good.
Cost to repair mine? About $280 parts & labor. Each.
Cost to repair yours? May depend on how easy it is to get at the CPS. On mine it's horrible.
haul it to the auto wreckers. save anymore time, once a motor is heated up things get warped like the heads. even wore lobs on the cam shafts just from high miles , make sure the timing gears are lined up right it could be of one notch. it will run like shyt ..
Timing belt is one tooth out