I need help with my 1994 J30 Please and Thank you Too!

[Sweettoze]

I am going to try to not sound like a total idiot, I hope I succeed, but I doubt it.I bought my 1994 J30 a month ago. It has 58,000 miles. Three days after I bought it I was on my way to the DMV (this was the first time I had it on the Highway) somewhere around 60 -65 mph I felt a slight surge or slip and both the check engine and the oil lights came on. I pulled over, sat there for minute then got out and checked the oil, it was the fine. (The previous owner had it changed the day I bought it.) I decided to get back in the car and keep going. When I started the car, the lights were still on within 2-3 minutes they went off, then on again, then off again. Round trip to the DMV is roughly 20 miles; lights came on then went off around 8 or 9 times. The next day I took it to a mechanic, he said the computer showed no code or record of any code indicating that the lights had ever come on at all; and he could not duplicate the problem. Since my car knowledge is minimal, my logic told me surge/slip problem, hmm…could be the transmission. I figured the transmission had probably never been serviced and it couldn’t hurt, so I had that done. But of course, it didn’t fix my problem. Although, the lights have not come on again, it is still surging and a lot more often. I have noticed that when it surges the rpm’s will briefly jump up as well.I have been thinking, ( A dangerous concept for me, lol) on the way to the DMV that day it was over 100 degrees outside, I have been running the AC on high just about everyday since then. Could this have something to do with the problem? My husband says no, but he is no mechanic either. Does anyone have any ideas? I hope I have given you enough information, I can’t think of anything I forgot. But then again, if I thought of it, I wouldn’t have forgotten it, would I?p.s. I am not a blonde; I just act like it sometimes. Thanks for any help you can offer. Sweettoze

[goody90q45]

I don't own a J30 but had this site bookmarked. Lots of diferent DIY repair instructions and there is one on a faulty headlight relay which may be the problem. It doesn't look too difficult to look at the relay for loose wires and the replacement cost is cheap if you order through Joe.

http://fuzzycats.com/j30_diy.htm

I will let one of the experts answer to the other problem you are having with the engine.

[maxnix]

I figured the transmission had probably never been serviced and it couldn’t hurt, so I had that done.

Could you define this "service" in detail?

Sounds like maybe the IAC, but I don't know a thing about VG30DE.

[Q451990]

I would first start by jiggling all of the electrical connectors you can find under the hood while the car is idling. If the idle speed changes, then there's a problem there. Open the connector, clean and lubricate with di-electric grease, and see what happens.

If that doesn't fix it and the problem is fairly consistent at this point, I would take it to the local dealership or better yet someone local who specializes in Nissan Z's.

Don't think the headlight relay is your problem unless the headlights are flickering on and off...

Heath

[DAEDALUS]

The mechanic you took it to didn't bother to measure the oil pressure? The check engine light coming on means you might not get to where you're going. The oil light coming on means your engine might be close to death. Without lubrication parts will grind. The oil light is probably the most critical indicator on the vehicle. It could be an electrical problem, but that needs to be verified ASAP before you drive the car any more.

[driverdriver]

You should get an oil pressure check done and a cylinder compression check done.

Check your tailpipe(s) for a thick deposit of black soot.

Do you smell any coolant or "burning " in the exhaust?

If it is a transmission sensor problem, the ECU has a hard time capturing a code. Its best to drive around with the scan tool plugged in.

[metaverse3]

A lot of good advice...

Add fuel delivery system to the checklist. Have your mechanic/garage check the fuel circuit consisting of Fuel pump, Fuel pressure regulator, Fuel filter, Pump Relay. Connect a pressure gauge to the fuel system and take the car for a drive while monitoring fuel pressure.

Check the exhaust system. Clogged catylytic convertors can cause this.

Post back and update us with the status..

[Sweettoze]

WOW!!! Thank you guys so much for your super fast responses. I will print them all and check them off as I go. I will check back in you and let you know how I made out. For starters I think I will look for a different mechanic.There is just one more thing before I go. I talked to the previous owner today, he said he never had this problem. The only thing he could think of was the oil change. Previously he had only used Pennzoil oil. The day I picked it up he had it changed at Mobil1, and they used Mobil Oil. Could this make a difference? Should I have it changed again with Pennzoil this time? What about a synthetic oil? Thanks again for all the great suggestions. I will be in touch!

[metaverse3]

Oil should not make a difference. However, overfilling or underfilling oil in the enegine can cause issues. Check the oil level with the dipstick using the owners manual.

I did a change from regular kendall oil to Mobil 1 around 50k miles on my own J30 with no issues, so no worry there..

Synthetic oil is the best option to run in the car..longer oil change intervals, better protection etc. I would maintain synthetic if possible.

Good luck. Problems like these can be frustrating..

[infiniti tech]

Sometimes when the alternator goes bad it will turn on some warning lights. Most likely the battery light will come on but I have had a lot of customers over the years say this or that light came on and they did see a light just not the one they told me. I will say it is unlikely it would turn on the check engine and the oil light.

[Sweettoze]

Sorry I'm a little late with this response but thanks for all the help. Turns out it was the O2 sensor. You guys are the best. Thanks again.

[Q451990]

Sorry I'm a little late with this response

Oh... it was only a year later! Thanks for letting us know what fixed the problem!

Heath