Hello...any help is GREATLY appreciated...

I have a 97 Max SE -- Auto with a hair under 100K miles.

For a few weeks now, my car has been wonky...I start it, it revs around 12-1300 RPM, and will idle normally at temperature. However, more often than not, the engine RPMs will wildly fluctuate up and down, sometimes cutting out altogether (sometimes, it'll hang on around 200 rpms, then jump right back up to 800).

Its getting to be dangerous...When this first happened, it was confined to reversing and slow starts, but now, even at highway
speeds the car will sometimes feel like its pulling (RPMs will drop, but, not from 2500 to 500, more like 2500 to 2300, still scary )

OK, since this problem started, some codes have appeared:

Front Right Heated O2 Sensor (twice)
Knock Sensor (three times)
Mass Air Flow Sensor (once)
Rear Heated O2 Sensor (once)

IDEAS? THOUGHTS? HELP ME!!!

I love my Max, and owe far too much to let it suffer like this!

thanks all!
G.

 

Whens the last time you tuned up your Max, Plugs(15.00plugs), Wires, fuel filter etc.?

 

HI -- Thanks for the reply:

PLUGS -- last summer?
WIRES -- ?
FUEL FILTER -- ?

 

Don't have wires. But from the codes that you've been getting it sounds like you have an air leak somewhere. Make sure there are no vaccuum hoses cut off. It could also be a faulty MAF sensor.

 

mine was a similar situation... it would stall out on occasion, usually when just started or just up to temp, but always random. daniel B martin insisted it was the coolant temp sensor... he was right. anyways, some days or drives would be fine, others it would stall (always at a bad time). i did my fuel filter first, and that did not help, i doubt that is the problem with yours either. search for coolant temp sensor, and try doing the voltage checks that Dan mentions, it cant hurt. goodluck

Hall

 

Clean your throttle body out.

 

Here's an idea.....take it somewhere & let them tell you what the problem is?

 

I had the same problems on mine. Cleaning out the air filter and tb body worked out fine..

 

Hello everyone, and thanks for the replies.

Some new information about my car which I thought might help:

I had a stuck injector replaced last year...
I put in a new air filter last summer...

When a had a similar problem to this in the Autumn (although, far less so), the Nissan dealership said that it was simply a loose wire -- but, they never let me know which one...thoughts?

again, much appreciated!!!

best,
flo_boy

 

about the coolant temp sensor...

FIRST clean the throttle body, its easy and cheap... if that fixes it, you are lucky, and it should be done anyways..

if that doesnt work, it still sounds similar to my problem.
check the ECU for any codes, and see what COULD be the problem.

the coolant temp sensor controls how rich the car runs at different temperatures. doesnt effect the engine temp. when its cold, its gets more gas, the sensor will screw up, and basically stall it out by running it lean or rich. it was a long stretch to believe it, but it sure worked, after stalling every other day, it hasnt stalled again for months since the fix. give me a few more details about your prob, and i'll look around and see what it could be. i owe Daniel B Martin for this one, i miss him

Hall

My first thread on Coolant temp sensor

Another post about the sensor from me

 

Alot of people who have been on here when he was around owe him. I thought he was only leaving for a bit when he left his last post but it looks like it is maybe permanent.

SuDZ

 

I had almost the same problem few months ago, for me it end up been the TPS going bad it about 75 bucks at the dealer.