'94 J30t EGR Temp Sensor

[PNWj30t]

I'm the new girl to this group and have a question about my '94 J30t. For the last several months my "Check Engine" light has been coming on intermittently. Now it's on more than off.

There's no Infiniti dealer within 3 hrs of me, but the local certified BMW/Mercedes/Jag tech said that, since my car was originally from California, that the problem was the EGR Temp Sensor.

He was going to charge me a fortune, so I got the Sensor from the Scottsdale Infiniti dealer seen on this site - they were very helpful. So....now that I have this thing....is it something my son can put in for me? - or does it take programming of the car's computer or something complicated? Thanks for any help you can provide! Denise in Port Angeles, WA

[VimyJ]

OK. Go to a Nissan dealer. The J30 has the same engine as the 300ZX and the Pathfinder. Nissan knows all about this engine. Has them do a diagnostic to find out if in fact it is the sensor. Many things can trigger the check engine light. If you have the boxed mini full service manual from the trunk you can fnd out how to recover codes directly from the ECU (engine control unit). This maybe something your son can handle. If the code indicates something that has nothing to so with the EGR (exhaust gas return) you can return the part to Joe.

Some Nissan dealers say they don't do work on Infinitis. Work around this. Tell them how far away the nearset Infiniti is and that you are aware that your J30 is equipped with the famous Nissan VG30DE engine.

[Q45tech]

The Pathfinder has a different engine family from the Z/J30...intakes exhaust no VVT in 94 a truck engine.Many times a clogged EGR tube won't let the EGases flow enough to heat the EGR sensor..........clogged tubes are more common than failed sensor.

[VimyJ]

Yes, the Pathfinder engine is definitly a different set up but it is still a member of the VG engine series and most likely shares things like the timing belt, water pump, ERG, etc., OBDI .

[PNWj30t]

Thanks so much for all the advice - today's my day to follow-up. I also appreciate the input on the other Infiniti forums - about tires, and such. Having taken my studless snow tires off today, and looking at the tread in my all-season tires, I can see that'll be my next purchase.

[autotech43]

While the engine is warm and at idle, you might try and reach under the EGR valve and lift the valve off of the seat and see if you get an engine stumble. One sure way to find out if you have an EGR clog, but also depends on where the clog may be located. One way the ECM knows that the EGR has a malfunction is from the EGR temperature sensor, which as the EGR flows past the temp sensor the voltage will decrease in value. Most cases, the voltage will be around the 1 volt range when you have (no EGR) flow, and the voltage will decrease when you do have (EGR flow). There are no real specific values on that particular sensor due to the hot and cold ratio will somewhat affect the reading. The ECM is looking for the change in voltage! In my experience, 99% of the time with that particular trouble code, the EGR tubes are clogged, after the cleaning of the EGR tubes(right and left sides), I would recommend a BG air induction clean.