KA24DE help!

[Kougeki]

I bought a 91 240 about two weeks ago. It ran fine, and i was gonna do a tune up, but then it started acting funny. All of a sudden, the engine starting vibrating, then shaking at a stop light. I changed the fuel pump cause i thought it was too lean and the plugs. Still the same. I pulled all plugs while running, and the third one wasn't firing. People tell me it might be the injector or the spark plug wires.
Any pointers or tips would be appreciated.
Thanks.

[AznDrftr.]

Get new spark plugs then and try that out. If you misfiring in your 3rd then you very well maybe runnin on 3 cylinders.

Check all that.

[MoSinister]

People tell me it might be the injector or the spark plug wires.
Any pointers or tips would be appreciated.
Thanks.

If you suspect the plugs or wires, a quick swap with one of the others should verify whether it is or not. Yeah, it's obvious. But you didn't mention if you've tried that already.

Regards.

[Kougeki]

I swapped the wires and it's the same. I pulled out the third one while it was running and it sparks as I pull it out, but the engine runs the same. There isn't a change in the idle. When i do it with the rest, it REALLY struggles.
I think it might be the injector now. I'm not 100% sure though.

[aznpoopy]

to test the injector swap it with a spare or another

to test the harness try to shock yourself. j/k. get a test light

[eclipse_dsm]

I would clean the AICV with a Carb Cleaner and Maf Sensor with Maf sensor cleaner. Had simiar issues but I ended up removing all emissions parts cause I went turbo. Hope this helps.

[cloudstrife930]

swap injectors with another cylinder, swap wires, spark plugs, and injectors, check for 12 volts at the distributor. check for fuel air and spark, those are the key ingredients that make an engine run. you can disconnect the maf as well see if it runs better, it will kick up to like 2500 rpm tho being in safe mode. you can also ohm out all the injectors, see if any of them seem to have excessive resistance opposed to the others, you can buy an inline spark tester and a fuel injector pulse tester to see if the right amount of spark is being made as well as proper pulse going to the injectors. I recently had the similar problem, mine stopped running all together, after driving through 3 feet of water. The MAF was shot, but its wouldnt turn over due to bad wiring doing to the distributor. I intergrated a 96 altima harness where I loss continuity, plugged it in got 12 v and it fired right up! Good luck! P.S. check for proper fuel pressure as well with a gauge.

[Kougeki]

Thanks guys, i pretty much went through all those tips and the the
problem was... don't laugh... the distributor cap.
It had a crack.
At least i know the rest of it is working fine.
Thanks a lot.