DivaGal

2001 Nissan Maxima SE Auto, 113,000 miles. This car must literally just hate me. Ok, in June, new IACV and TPS. About two months ago, threw a code for catalytic converter and has some angry sensors. Codes come and go for it though. Been running ok, but terrible gas mileage. Car also STINKS. Has for a long time. It did that same thing once before and turned out to be a bad coil, or coincidence, I dont know. Hubby checked catalytic converter parts, except the front one under the motor, the one that I guess goes to the motor? Anyway, the parts he had time to check were ok. He's a truck driver and isn't here much. Anyhow, back when I changed the IACV and the TPS, it was done because the car would go into really high idle when I put it in park, or, the idle would drop almost all the way to a stall whenever the engine fans came on or I turned on the air conditioner, or, just for fun, it would drop but pick back up. Changed those parts and it quit doing that. That was in June. Now? The idle started fluctuating, up and down up and down, but not quickly, it would idle fine for a few minutes, then drop down to around 500. I think the idle was always too high, right around 8-900 rpms. It would drop down to 500 then pick back up. Over time this started getting worse and worse, to where it would take longer to pick back up, and then not pick up to the usual 8-900 but it would actually go to where it probably should have been all along, around 750. It would idle for a few minutes, then drop, then back up and stay fine and drop again. Anyway. Last night, it wouldn't even start. It made like a really fast drumming sound, I dont know how else to describe it. On the 3rd try, it started. Seemed ok enough, the usual roughness but nothing new. I had no choice but to drive it to pick up my daughter. Got to the driveway, which is less than 1/2 mile from my house, put the car in park, and it died. No problem restarting it. But, every time I took my foot off the gas, it would go to stall again, so I had to race it home (it didn't really get any speed, I hit around 40MPH at 3000RPMS) but I kept my foot on the gas all the way home. Interesting trying to reverse out of a driveway, then put it into drive, without stalling. Got it home, put it in park and the stupid thing didn't stall. I didn't sit there forever though. I shut it off. Started it again. No trouble starting but the car sounds like crap. Just really rough running. And like I said, the car gets horrible gas mileage. And that smell. That smell was there. My husband and his two brothers want to full with my catalytic converters, but I just dont think that's it. Not from all I keep reading. So, here I am, you guys seem to always have an answer, so I thought I'd give you the low down. As it stands, I wont drive the car now. I can't afford to be towed home. I dont have a cell phone and I have no family or anything around here to help me if I'm stuck on the side of the road, or IN it. I don't really need any of this right now as we've not been bringing in any money and I'm still trying to pay the rent. So, do you know of any cheap and easy ways out of this mess? Or am I just going to have to go without a car until I can afford 250 dollar parts? Help? Thanks! Pamela

Grand_hustle17

iTrader: (22)

i cant read all this man.. sum up the story a lil better next time but i saw key terms in this whole written bible lol... "certain rpms, 3000, 4000rpms, topic" based on those you seem to have a MAF related issue

Tonyrizzo21

Agree with MAF going. Had exactly same symptoms in my car, 60$ ebay MAF, ten minutes to switch out out, problem gone. Good luck, hope its as simple for you.

biggmike717

Hello im new also...what is MAF..my car sometime acts like it wants to stall also...but i have still a 30000 mile warranty left..

Grand_hustle17

iTrader: (22)

^^^ at this point its good to do a lil researching on your own instead of wanting spoon feeding... anyways MAF= Mass Air Flow.. the sensors tend to go bad in em... just do like the above poster said... type the keywords in ebay or google and search ur year n you will easily learn what a MAF is

foodmanry

iTrader: (15)

Sounds like you have two separate issues:

1. Bad MAF
2. Clogged or bad main cat

I don't know how your husband checked your catalytic converter because he would have had to remove it to inspect it thoroughly enough. With the age of the car it seems the main cat needs replacement as they will wear down/out. You can get it replaced at any exhaust shop. It will likely clear up the code issues you have, if you still have any...I wasn't clear on this.

DivaGal

Thank you for your help! I have had code issues, nothing in the past month though. The car did throw a code, I forget what exactly it was, a month ago, but that is when the idle started going crazy, and my husband took it over to Autozone and came back and told me it was my catalytic converter. They (codes) come and go, but most always, they have pointed to O2 sensors or catalytic converter problems, and in the year I've owned it, at one point, it said something about my fuel mixture. But it has read for the catalytic converter before too, and kept on going. The codes dont seem to be very reliable. It read O2 sensor another time it broke, and I ended up replacing an ignition coil. As for the catalytic converters, yes, he did take them off the car. EXCEPT the one part in front, I think its that curved part that comes down off the engine area? That one. He doesn't have a bunch of time and unfortunately, the car started acting up the night before he had to leave to go back on the road, so he just forgot all about the front part. I've been driving the car for a month since he checked on it, then last night is when it finally had enough of that. Either way, from all of the reading I've been doing, I say its most likely the MAF and the catalytic converter. The car has a whole bunch of problems, but by the time I can afford to fix something, something more major happens to it, like now, and I have to fix that first. You'd never know by looking at her that she has so many problems. That will teach me to buy a car because its just so darn pretty and still fits the kids in it

foodmanry

iTrader: (15)

Yeah, never buy a used car by how it looks. Always get it checked out by a reliable, trustworthy mechanic. Worst case scenario take it to the dealer and have them inspect it. They will usually tell you there are a 100 things which need attention.

You have three cats total on the car. Two pre-cats and one main cat. The one you say your husband did not check is the front pre-cat.

I'd say replace the MAF at this point and do a reset on the ECU. To reset basically disconnect both battery cables, step on the brakes a couple times (to get rid of any lingering charge), and reconnect the battery cables. Do the reset while you change the MAF (have the battery cables disconnected while changing MAF, then reconnect after new MAF installed).

If it is the MAF you will notice an immediate difference/change. If no change, then the cats need closer inspection and likely to be replaced.

Darkrock

1. There is no basis for a parts change until it is diagnosed correctly.
2. You need a multimeter and the FSM (Field Service Manual) to correctly diagnose this without a rock solid lead from a SES code.
3. Since the IACV and TPS were recently replaced you should verify the IACV has continuity at all posts and that there is 22ohms resistance as indicated on page EC-436. Second, is a question ...the TPS needs to be dialed in when replaced and if you didn't do it then you may have shorted the IACV. But if you bought it from Autozone then you should have a warranty.
4. In the FSM go to section EC then look for the pages for the P0505 code and start the diagnostic from there using the information noted for WITHOUT CONSULT II.
5. This is not an easy task but go back to what you recently replaced and verify functionality first before throwing parts at it.
6. Also what does the "stink" mean as in smell? If it smells burned then you have shorted a section of the ECM which is a hallmark of the 2001. Then search the forum for "fried ECM" good luck.

foodmanry

iTrader: (15)

Yeah...but she changed the parts in June of 2011 which corrected her high idle problem then. Now, all of a sudden the IACV or TPS would go out? Doesn't make sense....

Considering the car is 10 years old and has never seen a new MAF (I gather this from the history of the car she described) it won't hurt to change the MAF.

Plus...she doesn't have TIME and expertise to do all of those things. Time and expertise is what she is short of.

DivaGal

Well, I let the car sit for 3 weeks, didn't have a choice, nobody here to help with it. Brother in law comes, sprays stuff all over the place, I seriously dont know WHAT he sprayed but the car was ok, according to the men. It hasn't stalled, so I guess that meant FIXED to them. NOT to me. Still having the idle drop but it picks back up. For now. I am picky, I've been on the side of the road with my two kids, 3 times last summer alone (had a Mazda MPV with a serious timing belt problem) and not looking to do it again. I said MAF, nobody listened to me LOL! I'm getting the MAF. Will pay for it to be done I guess.

I didn't exactly buy the car because it was pretty, although that was the main thing, LOL! I drove it, it worked, seemed like a good plan since I was driving that killer mini van for so long. Paid 3800 for this car, taxes and all included. Is it worth it to replace everything it needs? I wonder. I consider throwing in the towel pretty much every day. I have front end issues and motor mounts that are bad and I can't ever get to them when I'm having to just keep this thing running, money is short. I have two bad outer tie rod ends, a bad drive axle, have already replaced the hubs and bearings but I'm not feeling like it was done right, I have NO ABS sensors, apparently all were cut? I've never even gotten to the spark plugs, and I'm absolutely sure they need replaced. I wont even get into the air conditioner, nobody can explain the mess there. Whoever had the car before me, I am assuming probably correctly, they did NOTHING but drive it. So, seeing as how I paid 3800 for it, if I were to practically rebuild this thing, opinions here, do you think its worth it? Thanks for all the input!

Mr. Brett

iTrader: (7)

TL;DR