crank pos. sensor question

1shotjake · #1 05-31-2008, 09:11 PM

Well I am a n00b here, and have had my 92 ext. cab 4x4 (318 mag of course) for about 3 weeks now. Just have a few questions as I haven't been able to find much about them whilst paging through.

First, recently on my way home for work (freeway speeds...) I noticed upon trying to accelerate, pushing the pedal more than about a 1/4th of the way down it begins to sputter and backfire, and (as a result I assume) I have some hard shifting (auto trans) between second and third I think, and finally kicks into fourth and rpms drop and everything is fine.

I pulled codes and got 12 and 21, So it says my o2 sensor is meh. I'm not quite sure that's the problem so I talked to my buddy w/ a 96, and he suggested it might be a bad crankshaft position sensor.

In addition to this I think my fuel sending unit is going bad as well (currently whines at idle) but I'm not sure that's the problem either.

Any other ideas?

and just a few other side questions, the motor was rebuilt about 85k ago and the tranny about 1k, and i figure things may not be quite stock, and in the fuse box it seems as though i am missing the radiator fan (which runs continuously) relay and the ABS relay, will this cause and problems? also anybody have any suggestions for dealing with rust around the outer edges of wheel wells/fenders? I figure theyre gonna need replacing or, cutting w/ some patch pannels but I figured I'd ask anyway...

Thanks in advance and appologize for such a long post.

dodgerules86 · #2 05-31-2008, 11:16 PM

As far as the reason for the post, I'm not sure really. I know the TV cable can effect shifts and sensitivity, but I don't know if it would, or could, have an effect on how the engine runs.

Some fuel pumps run louder than others. I can hardly hear mine, but on my friends Cherokee, its quite noticable.
As for the relays - the radiator fan relay is for 4-cylinder engines, which is why you don't have one. The ABS relay is used only on vehicle with 4-wheel ABS (the relay is not used with rear-wheel-only ABS)

zman17 · #3 06-01-2008, 07:28 AM

You have that 21 code and need to check and replace the 02 sensor(s) and eliminate the problem first before going on and trying to diagnos anything else.