Running stupidly rich ... any ideas?

RG.net · Postby **RG.net** » Wed Jul 22, 2009 6:19 pm

ampz wrote:You won't see any difference on the sensor visually.
The only way to test it is to measure it's resistance when cold, then when hot.
If it's within certain levels (I don't have an NB manual sorry) then it's either good or bad.

I usually just look for a different ohm reading between hot and cold, but that doesn't guarantee it's not within specs. The only temp sensor that died on me went short circuit (0 ohms) and stayed that way hot or cold, so was easy to diagnose (wasn't an mx5).

Intresting, i'll give that a shot sometime this week. I might chuck the old intake setup on first though.

thanks again.

corners · Postby **corners** » Tue Mar 30, 2010 9:54 am

How did you go with this?

Shinigami! · Postby **Shinigami!** » Tue Mar 30, 2010 6:08 pm

most factory computers are designed to run rich on cold starts, that is why the idol is high compared to when the engine is warm. that is what i understand.
and the puddle from your exhaust on cold idol is condensation(water).
another reason as to why your car is running rich could be due to you intake as its sucking in air quicker/less restricted so the afm/maf tells the ecu to dump in more fuel.

ps: i may be wrong.

RG.net · Postby **RG.net** » Tue Mar 30, 2010 6:33 pm

Wow, this is an old thread.

I did fix the problem when the car was ripped apart, some vaccum lines were going into the wrong sensors, I think the one of the fuel pressure lines was hooked up incorrectly too.

Runs great now, still runs rich but not to the point where it's spitting fuel on idle. My Jaycar DFA will let me lean it out and grasp more power too.