J30T Problem

[infiniti1995j30t]

I have a 1995 infiniti J30T, it does have a knock sensor problem and idk how to fix that i was told there was a bypass i could do but never looked into it, but the engine light is on due to the knock sensor. Its ran ok with the knock sensor problem but the other day the engine light went off for about 3 hours then came back on and now i have a nasty fuel smell coming out of my exhaust and the car is getting really bad gas mileage but still runs the same, what should i do to fix this problem. The engine light has been on for 6 months cause of knock sensor but never had a problem like this.

[GerryO]

O2 sensors, catalytic converter, MAF, air filter, old spark plugs?

Any mis-firing? Time to pull some codes, and on a '93 a failed KS doesn't cause the CEL to turn ON, but it sure affects how the transmission shifts. I suppose it might on a '95.

I also believe fuel mileage suffers in colder weather.

[infiniti1995j30t]

the codes come up for knock sensor... and the car runs fine, once in awhile it oddly dies but starts right up then runs fine, a MAF wouldn't cause a strong fuel smell in the tail pipe, air filter is clean, sparkplugs are not that old, o2 sensors seem fine, catalytic converter seems fine

[yodawill2000]

are you sure the fuel smell is from the tailpipe ??I just fixed a fuel smell leak in cold weather by replacing a few fuel lines on the engine.the symptom was a strong fuel smell until the engine warmed up.The old lines would swell up when warm but leak when cold.easy fix.

[infiniti1995j30t]

well, if i get close to the tail pipe yeah it smells of gas badly, but maybe its a line still? guess ill check it out again

[Jissen_kenbu]

the codes come up for knock sensor... and the car runs fine, once in awhile it oddly dies but starts right up then runs fine, a MAF wouldn't cause a strong fuel smell in the tail pipe, air filter is clean, sparkplugs are not that old, o2 sensors seem fine, catalytic converter seems fine

MAF do some screwy stuff trust me. Im a nissan tech. lol It doesnt take much to check simple stuff like the MAF. Also the Injectors are NOTORIOUS for failures. It seems likely its an o2 sensor or an exaust leak or maybe a leaky injector. If i were you i would have changed the knock sensor 6 months ago lol. It might be possible you you jumped timing?

[infiniti1995j30t]

MAF do some screwy stuff trust me. Im a nissan tech. lol It doesnt take much to check simple stuff like the MAF. Also the Injectors are NOTORIOUS for failures. It seems likely its an o2 sensor or an exaust leak or maybe a leaky injector. If i were you i would have changed the knock sensor 6 months ago lol. It might be possible you you jumped timing?

For u being a nissan tech u should know how hard it is to replace a knock sensor in the VG30DE 3.0L motors, dealer alone charges $1200 to replace the $60 sensor. i never heard of a exhaust leak causing a raw fuel smell, and if i had a injector problem i think the car would run bad, but maybe a o2 sensor.. and to say the car runs the same as it did before this happend
Modified by infiniti1995j30t at 6:46 PM 12/19/2008

[j30t_Dan]

Everything the guys said is a really good call. Sounds simple, but are you running synthetic?

[infiniti1995j30t]

Everything the guys said is a really good call. Sounds simple, but are you running synthetic?

synthetic oil? If so then no, the car has never had synthetic oil put in it.