Any Ideas

[ihenson711]

Hey Everyone,

I have an 02 Ser Spec v.. and am having some issues. Two days ago I stopped at a local Shell Station and filled the tank with 91 premium gas.. hopped on the freeway and ended up at work. On my way home that evening while I was getting on the freeway the car started acting like it was missing or something. I would try to take off and the car would kind of stutter, and then it kept stalling. I was able to limp the car through traffic and open it up once the freeway cleared.. it continued to act like it wasnt getting enough fuel. After getting home I thought it was probably bad gas so I added 2 bottles of heet dry gas, and some lucas additive to the fuel as well. Since then I have ran octane booster, Seafoam, and have filled the car once again with 93 prem this time.. Now I am aware of some of the issues such as the butterfly screws, pre-cat.. etc.. and the recent ECU recall all of which have been taken care of. I took the car to the dealer 2 days ago to have the ECU reflashed under that new campaign. The car has seemed to smooth out a bit but it still stutters like it has moisture passing through.. and it seems to happen when I am cruising on the freeway at an even speed with my foot on the gas just enough to keep an even speed. My car has 81,000 miles and is well maintained, this issue did not arise until after that first day at the gas pump which has been about 5 days ago.. I called a guy at NAPA today who knows alot about nissan, and based on what I told him he said that it sounds like I still have moisture in the fuel system, he said he would undo the fuel rail supply and purge the line.. Any Ideas!!!

Thanks, Ian

[nametakennow]

Could also be a bad MAF, which is an easier job. Unfortunately, it's hard to diagnose one over the other, so you may just have to choose which option to try first.

If you go with the MAF, find one from a junkyard, new ones from Nissan are ridiculously expensive.

Welcome to NICO!

[ihenson711]

Thanks so much for your reply.. I am glad to be a part of nico..

[ihenson711]

One quick question reagarding the MAF.. Generally if the MAF is bad or causing problems would it cause the CEL to come on? Just curious.. as the CEL has not come on at all..

thanks

[nametakennow]

The CEL may flash once or a couple of times when it happens, but since the car runs most of the time, the CEL doesn't get triggered.

It's kinda stupid, honestly, that the MAF isn't a stay-on diagnostic code.

[ihenson711]

Yeah I agree.. I have not seen a CEL at all since this issue arose. The guy at NAPA said that the MAF sensor on the Spec v is extremely sensative though and he recomended the CRC maf sensor cleaner.
Modified by ihenson711 at 12:41 PM 1/25/2008

[ihenson711]

Well I went ahead and used the CRC maf cleaner and it didnt help the issue. Actually I pulled into a Sonic to grab some food and while the car was idling it acted like it wanted to stall a few times. Also I have been able to narrow down when it actually stutters... it seems to be if i am driving at an even speed and my foot is barely depressing the pedal just enough to keep a constant speed. It makes the car jerk.. kind of like if you were rapidly tapping the gas pedal in like 2nd gear.. kind of that lurching feeling but really quick then it goes away.

[nametakennow]

Definitely sounds like a MAF symptom to me.

[ihenson711]

Is their any way to actually diagnose this, or is it simply buy it and try it? The only things that I have done to the car is a header, and I bought a CAI Filter and basically attached it right after the MAF sensor, but these mods were done several months ago and this problem just started.

[ihenson711]

Hey nametakenow are you out there?

[nametakennow]

Yeah, dunno how I missed the previous post.

Is the filter oiled? More importantly, did you oil it? If so, you may have sucked in some oil and killed the MAF. It's a very common and easy mistake to make.

Anyway, if the MAF is intermittent, there's no real way to be sure, as the voltage will read properly when it's functioning properly. If you could get it to act up with a voltmeter attached, you could be sure.

Try junkyards before buying a new one, they're way more expensive than they should be.

[ihenson711]

Is there anything else that you think it might be?

[ihenson711]

I was doing some digging on Ebay and found a MAF that says it is for the spec v, and it's 39.99 + 8 bucks shipping. I am going to paste the link will you take a look to see if it looks legit?

http://cgi.ebay.com/ws/eBayISA...h=005

[ihenson711]

If I were to test the MAF while it was messing up.. how exactly would I do this. I am not really familiar with how to use a volt meter.

thanks

[nametakennow]

While that is a MAF, Nissan integrates MAFs into a part of the intake piping. The Ebayer not knowing that makes me skeptical at best, don't do it. Try a junkyard.

You'd need to place the voltmeter contact on the signal wire. You'd be better off getting someone who knows how to help you.

[ihenson711]

Hey man thanks for all your help on this.. Do you know which wire would be the signal wire on the MAF sensor? And do i need to expose some bare wire to test this or is there another way to check the voltage. Oh yeah one more thing.. Do you have any idea what kind of voltage issue that the MAF would display when the car is acting up?

thanks a bunch/..

[nametakennow]

You'll need to look up the proper voltage range in the FSM. If it's acting up, it'll likely read out of the range or change when it should be stable.

The red wire is power, black is ground. The signal wire is probably white. The FSM should tell you the colors to double check that.

[ihenson711]

I am going to pick up a manual on my way home.. But as far as actually testing it should I expose a bit of wire on the signal lead, or is there a better way to touch that contact while it is running to check the voltage.

[nametakennow]

Probably going to have to strip a little of the wire. Take a close look at it, though, maybe you'll find some room near the plug to minimize the amount of stripping you need to do.

[ihenson711]

You have been a huge help... I'll let you know the outcome.

[nametakennow]

Glad I can help. Definitely keep us updated.

[ihenson711]

Well the Sentra finally threw a code.. P0113 IAT Circuit. I dont see an IAT on my car.. is this part of the MAF?...
Modified by ihenson711 at 6:53 PM 2/11/2008

[nametakennow]

Yes, 2.5 and 1.8 Sentras' IATs are integrated into the MAF assembly.

Even if it's bad I don't see it causing stalling, but it sounds like you're going to have to replace the whole shibang anyway.

Look it up at a parts vendor, maybe it can be separated.

http://everythingnissan.comhttp://courtesyparts.com

Then try a junkyard before you shell out the dough.

[ihenson711]

I found one local yard that has 3 MAF's that are all from the altima 2.5 he says that it will fit my car.. He is asking 75.00.. If I buy this it should include the IAT sensor right?

[Boosted4Speed]

90% of the time if the MAF goes bad you cannot rev over 2,500 rpm because the car would be in limp mode. So if you cannot rev over 2,500 rpm its your maf. I believe you mentioned an issue about bad idle which makes me think a bad o2 sensor or if you have a older 02-04 model you could have the precat issue which also would have similar characteristics to what your describing.

[ihenson711]

I dont have the pre-cat.. I have a header, and I dont think that the MAF is dead because I haven't had any check engine lights come up until the one today. Right after I got the car I loctited the butterfly screws and bought a header, I have had the car since 68000 miles it's got 82500 now. I have had no problems until a few weeks ago.

[ihenson711]

If the MAF was going bad could it cause the car to stall especially at an idle? This is what happened before the car threw the code. I had the car off and I was trying to check the voltage on the MAF.. while the MAF was still unplugged I turned the key to the on position to check voltage and then turned the key to the off position and reconnected the MAF. I then started the car and a few seconds later the SES light came on.. I flew up to autozone and that is when the P0113 code came up. Prior to tonight I have had no codes, and no Limp Mode.

[nametakennow]

Yes, it could. It acts like a vac leak if it's an intermittent issue, as when it gets dirty or there is too much vibration. Sometimes the MAF can be damaged without completely losing function. In this case, it won't cause limp mode or an SES.

That light probably came on from having it unplugged since the IAT is integrated, drive it a bit and see if it turns off. It can take 50miles or so for the code to disappear.

Does it do these symptoms while cold and/or does your water temp gauge bounce or seem to be reading lower or higher than normal? It's possible that the coolant temp sensor is shot.

By the way, Boosted, 05-06's are not exempt from the precat issues. Nissan hasn't entirely acknowledged it, but they do occasionally eat the precat and you can get a free engine out of it. The telltale sign of precat failure is high oil consumption and/or significant power loss. Since there's no precat involved here, it's not an issue anyway, but just an FYI.

[Boosted4Speed]

Well on all the 05-06's ive worked on have a different header then the 02-04's do (im sure they still have it but much more unlikely) along with the later 05's-06 used a different type of screw for the butterfly valves. When you unplugged your MAF did you have your battery unplugged?

[ihenson711]

Ive got a question.. So I went to a salvage yard and bought a $65 MAF out of a 2003 Altima put it on the car there and the car is doing the same thing.. I went straight back to the salvage yard and swapped it for another, and its still having the same problem. Here is my question.. If the check engine light is still on from the yesterday could this cause the car to still have issues until the code clears itself even if the MAF that I got from the yard is good.. or if the MAF is good should the car automaticlly just run normal even with the SES light still on.. or will the computer have to cycle through and clear the code before the new MAF will work properly???
Modified by ihenson711 at 1:23 PM 2/12/2008