Greetings! I've spent a couple hours searching and learned many things (Great site BTW) but I'd like some input to help resolve a few issues with my '96 I30 (VQ30DE engine).

I've got a '96 I30 with 5 spd transmission with 204k miles, I've owned it since '99 (had 86k miles) and I have done almost all maintenance and repairs so far.

Current issue: Car has had several episodes of engine cutting out and stalling. SWMBO drives the car primarily now, mostly around town stuff. A few days ago she told me that it was stalling and running rough and she didn't want to try to drive it home. I drove the car home and at first it ran fine but after about 30 minutes of in-town driving (nice and warm) it stalled while at idle for a stop light. Restarted just fine, but then it would either buck really bad or cut off entirely if the RPM was too high or if I gave it too much throttle. At low RPM and low throttle, it seemed to be OK, but it would die easily at idle. Always restarted just fine. When it cut off, the engine just flat died like the ignition was off. I immediately suspected a crank sensor or camshaft sensor.

I pulled the codes: 0102 (MAF), 0303 and 0503 (both front O2 sensors), 0801 (vacuum cut valve / bypass valve), 0105 (EGRC solenoid valve).

MAF fails the component test: output voltage signal is supposed to rise to ~4 volts at 4000 RPM, it only gets to about 2.3 volts. Tried cleaning it with CRC MAF cleaner, no change. I think I need to just replace it.

O2 sensors are working, but they respond slowly. The front left sensor flat out fails the test, the front right fails about 1/3 of the time. I'm planning to replace both.

EGRC solenoid valve passes the component test, and harness is good, so I'm a little stumped here. The FSM test is only to apply power and make sure that air can/cannot pass through the various ports. Is there another way to test it? Should I just replace it on principle?

I haven't tested the VCV/BV again lately, but I have tried in the past and couldn't resolve it (see history below).

I decided to dig a little deeper, so I put the timing light on her and disconnected the TPS. FSM says timing at hot idle should be 15 deg BTDC, but I get about 30 degrees. Reconnect the TPS, and no change. Rev the engine, no change. I guess I probably need to fix the MAF and the O2 sensors, and then check the timing again. I also tested two out of three of the crank/cam sensors, and they tested fine, and I'm not getting any codes for those so I'm skeptical that any of those are the problem but I could be wrong.

So, I cleaned the MAF, adjusted the idle speed which was too low, adjusted the fast idle cam. For three days now the car is running fine for my short commute to/from work, and if I drive it hard around town for 45 minutes or so it does just fine, so maybe it just wanted some TLC? The timing issue really bothers me, and the car doesn't get mileage as good as it used to (dropped about 10 to 15%).


History: Back in July of 2001, at about 110k miles, on a hot summer day while SWMBO was driving, car started running really rough and acted like it was going to die, but after 5 or 10 minutes it got better and then ran fine again. Engine temperature was fine, oil was fine, nothing obvious, but shortly afterward the CEL lit up. I pulled the codes (0304, 0801, 1005) and knock sensor was bad, there was a code for the EGRC valve and the Vacuum Cut Valve Bypass Valve. I did the component checks on the EGRC valve and the VCV/Bypass valve, but both of those checked out fine. Harness was fine, signal at the connections on the ECU was fine, I didn't want to throw money at it and nothing else seemed to be affected, so I decided to live with the CEL on.

A couple years later I found a cheap source for the knock sensor on Ebay, and fixed that problem. Periodically I would pull the codes to see if anything new had cropped up. CEL even burned out on me, I shifted an unused bulb on the instrument cluster to bring it back to life.

Thanks for reading all this!

-Max