New MAF and still got issues

[BlackBirdVQ]

Well I have been experiencing alot of hesitation, uneven idle, very low power (will NOT spin the tires with the TCS off). I do need new knock sensors cause I am getting codes for them but will a bad knock sensor affect the VH that much ? I mean its kinda ridicilous in terms of power output. It seems to be alright as long as I don't go more than like 1/4 throttle. I got myself a brand new MAF and knock sensors from Infiniti today (cost an arm n leg, 380 for MAF and 130 each for the knock sensors) I am going to do the knock sensors sometime this week, but before I do all that I have to make sure the car no longer has a cooling system problem.

On Sunday my aftermarket radiator blew at the right end tank, previous owner said it overheated on him a few times with the new radiator so I am thinking that radiator just took a beatting. My new aftermarket radiator has Nissan stampings on it, and looks just like OEM so I should be alright. I am still dreading a blown head gasket which would cause the radiator to blow out due to pressures.

While sitting in park today idleing I noticed the car started to run rough- felt like one and then 2 injectors stopped fireing. After a short drive around the block it went away.

Did anyone ever have any VTC problems on the VH ? I know VE30DE in the 92-94 Maxima SE (DOHC 190HP motor) has issues with them causing low power, clicking etc.

I need to make this thing reliable again, as previous owner didn't have much of a luck with his Nissan dealership (who obviously has no clue bout the VHs) and local independent shops.

[Rex]

Have you checked your fuel pump? Is it humming?Have you ohm'ed your injectors?Have you run a can of BG44K? (the better ~$10 Valvoline works well)Any idea on plug age or type?

[gloucester Q]

what's a good time to replace the maf anyway? i had, over the weekend, a wildly erratic idle on startup, then over the course of a 50 minute drive, 2 seconds of stumble out on the highway. to answer rex's ?s for myself, i've got recent fp, injectors, plugs, and fuel system i believe is fairly clean. is the maf linked to mileage (90k) or age ('93), neither, or both?

[96Qowner]

I haven't noticed any particular correlation to mileage or age. As with most part failures it can happen over a wide range of mileage points. That being said, 90K doesn't sound too soon for a MAF failure, especially given its age.

Mine started to fail much the way you describe your symptoms. It started as one or two "bucks" a couple minutes after I'd hit the freeway and settle into speed. No big deal, but disconcerting, when you don't know what's wrong. I first replaced the fuel pump and then the filter. Neither solved the occasional bucking/jerking. Then I cleaned the MAF and the problem went away - for a few thousand miles. Every time the bucking staretd again, it was worse. Every time I cleaned it, it lasted fewer miles.

From reading the posts here, it seems the MAF problem has two causes. It's either a connector problem - loose and corroding wires inside, or corroded connector pins - or a problem with the MAF itself, or both.

If wiggling the connector while it's running doesn't change anything, plan to replace the MAF itself. If it's the connector, you can get replacement pins and housing from Joe:

zerothread?id=135741

You can clean the MAF and get some thousands more miles out of it, but if it's actually starting to fail, and not just dirty, you'll need a replacement fairly soon. Check out the Infiniti parts section on NICO, or ebay, or just find a parts yards through http://www.car-parts.com where they can be had for under $100.

[BlackBirdVQ]

Recap of what the car has....

New Fuel Pump has been installed previously by the last owner bout year or so ago.

When I purchased the said whipp I did...

*New NGK plats - checked the gap on all of them and regaped to the FSMs specs*BG intake manifold cleaner and fuel injection service- did it myself at work, ran 4 cans of cleaner through the engine.*PCV valve, and PCV hoses into the intake manifold.*New fuel filter.*Cleaned the pins on the MAF connector and put some dielectric grease on the connector.* New MAF as of yesterday- runs exacly as the car did with the old one.*New Thermostat as of last week *New Radiator as of Monday- OEM.

Things I still need to do.- Valve cover gaskets, leaking all over the exhaust manifolds causing people to stare at my *sometimes* smoking from under the hood at the stop light-Q.- all the intake manifold hoses and coolant hoses under the intake- NEW knock sensors, I got codes for both knock sensors showing up on the Consult- I am holding off on those till I get some new injectors.- NEED TO GET- new injectors, I have not ohmed them out but I noticed it more now that if I let the car idle for little too long when hot it will drop cylinders and runs rough.

I have all the gaskets, hoses, etc needed to do the job but I am still looking for a set of good 370cc injectors off a SR20DET (same as the Q) to install. The car has 2 or 3 new injectors from what I can tell by peaking through the intake manifold runners, and the previous owner left me recepits from Infiniti for injector repairs.

If the knock sensors do not fix the car, even with new good injectors I will hit my friend up to run my car with a Consult to see wtf is going on. It seems it runs pretty good at very little throttle, but lay on the gas and its not going anywhere. Trans doesn't want to downshift till I get on it hard and at that point the car isn't making any more power, so I am forced to drive it very very slow- but I did manage to get 21MPG so far.

Maybe my car has Infiniti's Displacement on Demand concept ?

[chinaonnitrous]

Hi Mike!!!! :

[Jeff Williams]

Maybe my car has Infiniti's Displacement on Demand concept ?

I feel that way sometimes, myself.

Have you thought about the TPS or CAS? Also, I have heard that the VVT assumes a base timing of 15 Deg.

All cars need the same things: fuel, air, and spark. Some are just a bit finiky about quality of fuel, cleanliness of air, and when the spark is.

[BlackBirdVQ]

Well I think TPS is a possibility, or bad injectors. I am going to be testing them out very soon and I will know for sure. I really want to do the knock sensors but I am sure a few of my injectors are shot and will not ohm out within specs. If thats the case I just wanna have a set handy to throw in to make it drivable again- with 100% of its power.

I am thinking I can have the KS sensors and all my coolant hoses repleaced tomorrow within 2 hours but I am too lazy to do this yet :P I'm hunting down a set of good injectors and then I will tackle the job.