I'm posting this for a friend as he is trying to figure out either what may be wrong or a good place to start.. Any ideas would be great.. Thanks..

1993 Nissan Altima GXE Automatic
Runs poorly / intermittent misfires
Radiator fans don't come on
Coolant leak coming from what appears to be the 'front' (passenger side) of the motor

Car runs but loses power / misfires. Car doesn't appear to overheat (as indicated by the temp gauge at least), but the fans never come on, even after driving and sitting in traffic. Lots of built-up oil sludge and coolant crap near the 'front' of the motor. Not sure if there's a crack in the block/heads or a gasket is blown--can't see anything thanks to everything being so tightly put together. Put new plugs in, ran a little better but still runs poorly especially once it heats up. It idles fine though oddly enough. Needs new sparkplug wires I believe (when you pull them out, they arc on the motor through the plastic--not sure if this is a cause or an effect of the problems).

There's what appears to be an IAT sensor coming out of the side of the air-box near the air-flow sensor, after the air-filter. It's a simple 2-wire sensor, the plug sits on top/side of the air-flow sensor. I can see something had been plugged into it before as the sensor prongs are worn, but I cannot find a harness to plug the sensor into. There's another sensor, what also appears to be an IAT sensor, prior to the air-filter, but it is plugged into a harness.

Also, how the hell do you change a belt on this thing!? It's as if you have to lift the motor out of the car. No history on the vehicle, just looking at it for a friend. I was going to degrease and clean the motor except all of the buildup is behind the belt accessories, and I can't see or reach behind them anyhow. The other sides of the motor are clean.

And wouldn't you know the check engine light is on?

 

well i dont know about all the other stuff but if the fan is not kicking on then you need to checked the temp sensor. what i do is i unplug the fan and hook it straight to the battery. you want to find some wire and hook it up just to see if the fan is working. if it is then it might be the sensor. for the leaking its best to clean the spot and then look. if there is stuff like plastic in the way take it off. and some cars it might be better if you take the wheel off to get to the drive belt. some times dont quote me. but its best if you get the helms manual. stay away from hanz manual.

 

timing chain? water pump? coolant temp switch?

 

it has a timing chain it will make alot of noise if it loose also they had a great deal of problem with the dizzy. take off valve cover you'll see the chain. iat isn't going to cause iny problems.