This has me puzzled. Any help is appreciated.

I filled up my 91 Maxima SE with mid-grade ethenal-blend gas a couple weeks ago (like I usually do), during a rainstorm. Next day while driving, my engine started a fast chugging and then stalled. I was able to start it again and it continued fast chugging. Fine up to about 1800 rpm then it chugged between 1500 - 2200 rpm. Stepping on the gas wouldn't get me beyond this RPM. Then all of a sudden it ran like normal. A few miles down the road it did it again. Then ran like normal again. I figured it was water or contaminants in the fuel so I put a bottle of Heat and Chevron Fuel System cleaner in the tank. Really didn't help much, so once I got it down to 1/2 a tank, I filled up with Amoco Ultimate and put a new Wix fuel filter on. It idled VERY smooth for about 10 minutes, then started putt-putting noise from the exhaust (which it previously did). It ran a little better until I got to approx 1/2 tank of this blended good/questionable fuel. Now I'm about 1/4 tank and it is constantly stalling on me while driving, waiting at stopsigns, etc. I have a difficult time restarting it right away. If it sits for a length of time, it'll start right up. It is still is doing the fast chugging thing too. I'm completely baffled as it is a sporatic thing. I did notice my lights dimming as I tried to repeatedly start it last night. I just had a new alternator, cap, rotor, spark plugs, spark plug wires a year ago, so it shouldn't be that. My driving is almost entirely less than 5 mile trips in the city.

I'm planning on running this tank dry, refilling with Amoco Ultimate again, changing the Wix fuel filter again, and perhaps putting more fuel system cleaner in. ANY OTHER ADVICE??? Anyone have a clue what's going on?

Thanks.

 

Check out your o2 sensor. My car acted like that a few months ago and once I changed it everything was back to normal.

 

Also check your MAF and your injectors.

 

Rain + VG + distributer/plug ignition = probably electrial problem. Next time it chuggs like that, remove the dist cap and see if it's wet with condensation. Or if the plug wires have 100k miles on them (like most VGs here do), one or more could be bad.

 

Checked the dist cap... bone dry. New Bosch performance plug wires installed only about 3k miles ago. My Maxima only has 86k miles on it. Could be the o2 sensor... my entire exhaust is ready to be replaced from Ypipe to muffler tips. (Held together with wire, fiberglass tape, and a tin can in one spot.) Planning on going the Warpspeed route as soon as the funds are available. Haven't checked the MAF or Throttle control for soil yet. Maybe this weekend I'll get to that.

I'm using the Haynes repair manual... poorly written. Covers 87-92. Mostly shows 80's cars. Can't find the Eccu computer under dash or under passenger seat. Where else might it be?

Thanks for the help. It is appreciated!

 

Dammm your exhaust sounds sick. Ok the ecu is on the right of the gas pedel. its the bottom box. If you are trying to check the codes go to the passenger side of the box you will find everything their. Ok also try the dist cap too. Mine did that too and it came out to be a hairline crack in it.

 

hehehe, i guess i wasn't the only one who had problem during the rainy days.

my take on this is the 02 connectors (attached in the engine mount). water probably sipped in in-between the metal conectors an shorting them out, making the ecu go crazy.

i had to parked my max for about a week before i was able to drive it again.

 

I sell o2 sensors

 

Man im having the exact problem. Tell me if the ECU gives you the 33 code. so far ive replaced the fuel filter, cleaned the throttle body, put 93 octane after running the old gas out, cleaned tank and engine with seafoam and im still having the same symptoms.

http://forums.maxima.org/showthread.php?t=356035

 

If you're asking me??? yes, i got a code 33.

 

hey check that thread again. i think what MAXI said is the case. only in mine my coolant was leaking on the connectors. But it was raining too. . .hmm

 

Ok, checked the ecu (Thanks silverlinekenne! Never would have found that one on my own.) One red light and two green ones. 12 means the air flow meter. MAF? I checked voltage on the pins and that checks out. Now what? Take it apart and try to clean it? Does it need replacement? Help please. I have a cheaper aftermarket Boomz cone air filter on my car, has this contributed to the problem?

Interestingly, as soon as I started the car with the electrical connector unplugged, it started the fast chugging thing when I put it above idle. Looks pretty convincing that this could be the culprit.