1990 240SX Misfiring/Wont Start

[KASilvia90]

1990 Nissan, KA24E. Automatic.

Ive had alot of bad problems with my 240, most of them have either gone away on their own, or i have fixed them. I have replaced the fuel pump, installed new injectors (rear one slightly leaky, will fix very soon).

Well the other day I put a new alternator on my car. I started it up, ran fine. Tromped it some, just like new. Well then I drive it 15miles to pick up some stuff. Ran fine going there then I got into my car, started it (fine) and got a block down the road to a stoplight and it was gluggin real bad (sounded like a freaking dragcar) and was bouncing idle between 375 and 750 in Drive.

I drove home and started it up the next day. It was gluggling horribly and when I revved it to 3krpm or so, i could hear a noticable miss in the firing. I pulled it in the garage and did alot of work to it. I took off my seized clutch fan unit (no fan...not driving it so no worried about voerheating yet), ripped off the a/c fan and hoses, evaporative core, and took out the radio.

I also then intalled a MSD blaster 2 coil and bosch super spark plugs (stock wires). I noticed my plugs were all fouled (my car was running overrich for a while a few months ago), and 3, maybe 4 were wet with gas?

After I got done reinstalling the ignition components, i came across another odd problem. The bottom bolt, closest to my headlights, on my exhaust flange was gone. So i may have a minute exhaust leak there.

I went to start it and it would would pretty much go, crank crank fire crank crank crank fire crank fire crank crank crank fire...etc. Couldnt get it to start. I had ALOT of exhaust from this event, and it smelled sorta like a mix of 2stroke and race gas (added methanol to gas in winter or something?). I checked my firing order, nothing was wrong. I don't know what to do.

I'm looking at either the slightly leaky fuel injector is REALLY messing something up (but has been that way at least 1 month prior to mishap) timing or MAF unit...I have a CAI and checked all my lines and everything, fine.

Sorry for the lengthy message, but detail is cruicial I guess. Thank you for any help. As of right now, my car is stuck in the garage and my dad wants his parking spot back

[steve s14]

that leaky injector is the first thing that i would look at. when you have a known problem with the car, take care of that first. as problems go, most will get worse as time progresses, generally it will not fix itself and go away. by ignoring a known problem, you might be chasing a solution that you knew about all along. it sounds like the engine is getting way too much fuel and that injector may be the cause. will the engine start if you floor the gas pedal and keep it floored while you crank it?

[KASilvia90]

I have tried to fix the leak on my rear fuel injector. I think the o-ring may have cracked upon installation and I will fix that with the help of a friend as soon as possible. I may have a problem there with a bent fuel rail or something, or I just have the tendancy to crack #4's o-ring.

I believe my problem is the TPS sensor. 2 Days ago my car wouldnt start at all because I got the +/- backwards on my blaster coil, i guess black w/red doesnt always mean hotwire. I checked for damage and other than a messed up rotor piece on my dist (may or may not have been damaged from that) everything was fine. I replaced the rotor, put the wires on the coil right and it started up.

It was gluggy when it started, i held the throttle lever beside the T.B. down to 3-4krpms for 60 sec, let off and rev'd to 3-4krpms abruptly, went back to holding, until my car was up to temp...It was running fine at that moment. Something came over me and I unplugged the wire connector going to the black box on the side of the throttle body (TPS?), it acted just like it had been! I replugged it, back to normal.

Today I started it and it was perfect idle cold and perfect idle warm. Hmm amazing eh? Just as abrutply as it started, it ended (just like 2 other times). Well I drove it around the neighborhood because I am also doing cooling system stuff and testing for overheating, when i brought it back into my driveway it was at dead center temp and idling fine...I took it out once again for about 2 minutes, perfect temp but whats this, glugging! OMG.

I took off the TPS connector and the glugging didnt alter, just a slight rev from the engine as it disconnected. Reconnected, still gluggly.

I think my sensor may be bad. It seems to show the syptoms of it being unplugged, when it is plugged in on occassions (lasting 2-3weeks and gone for a month). Maybe if i hit a bump to hard it makes something loose. Does this sound like a possible theory, or does anyone know anything about my situation? Is there a voltage I can check on the sensor, and how do I replace/fix one?

Like i said though, I think it is the TPS, it may be something totally different. But my symptoms as are followed: Very low idle, gluggly, doesnt feel like its running all cylinders, shaky engine/body, seems rich but can't tell for sure, randomly happens and randomly stops....Syptoms are similiar but not identical to what happens when i remove the wire connector.