problems problems problems

Alphamalez32 · 02-19-2007, 05:02 PM

I have a z32 91 and my mass air flow sensor wasn't working so i kept driving the car for about 2 weeks. Now i got a mass but the car idles worst than it does without it.
It doesnt even want to change speeds, if it does it does it at more than 3700 rpm or even much higher. Some times the car shuts off and gives me a hard time to start so some times i have to take the mass out in order to star it.
even though this mass i got makes my car limitates at 7500 like it is suppose to be it gives me a hard time to rev it up. the engine shakes and goes crazy and if i let the gas go it will shut down. I think is the used sensor i got but im not 100% sure. I tried disconnecting the battery several times so the ecu could try to adjust it self but nothing works. Any ideas, i will try to replace my mass but im not sure if this is the only problem that im having.

k3smostwanted · 02-19-2007, 11:55 PM

Quote:

Originally Posted by Alphamalez32

I have a z32 91 and my mass air flow sensor wasn't working so i kept driving the car for about 2 weeks. Now i got a mass but the car idles worst than it does without it.
It doesnt even want to change speeds, if it does it does it at more than 3700 rpm or even much higher. Some times the car shuts off and gives me a hard time to start so some times i have to take the mass out in order to star it.
even though this mass i got makes my car limitates at 7500 like it is suppose to be it gives me a hard time to rev it up. the engine shakes and goes crazy and if i let the gas go it will shut down. I think is the used sensor i got but im not 100% sure. I tried disconnecting the battery several times so the ecu could try to adjust it self but nothing works. Any ideas, i will try to replace my mass but im not sure if this is the only problem that im having.

the car should not run at all without a MAF sensor. Mine came loose one time and the car instantly died. If the ECU cannot read that there is any air coming in, it will not send fuel thus shut down your engine.

i dont know what your situation is with your MAF but maybe the previous owner rigged something with resistors or soemthing.

once you get the MAF situation figured out it will be easier to figure out why the idle is so disrupted. could be AAC valve which contains the FICD(?) solenoid. could also be a bad TPS (Throttle Position Sensor)...

another thing, go around the engine bay and clean the contacts on all the sensor wiring harnesses.

ExTrEmEDrIfT · 02-20-2007, 07:35 AM

yah maybe loose wiring like k3 was saying , and this talk about disconnecting battery so ecu could adjust itself itself is bull at the most its gonna clear the codes ( if you doit right) and then it will have to run through all the drive cycle parameters ...

try checking to see if any dtc's are stored in the ecu..

Alphamalez32 · 02-20-2007, 12:06 PM

My car does run without the mass. I actually dont even have it connected to the plug. i just have it there so nothing too big could go inside the engine through the hole. AS I said the Mass is unplugged. and my car idles better without it that with the used mass i bought

k3smostwanted · 02-20-2007, 06:56 PM

Quote:

Originally Posted by Alphamalez32

My car does run without the mass. I actually dont even have it connected to the plug. i just have it there so nothing too big could go inside the engine through the hole. AS I said the Mass is unplugged. and my car idles better without it that with the used mass i bought

what i am saying....that shouldnt be possible. your car should die without the MAF connected. without the ECU knowing of any air coming into the engine it will not know how muc fuel to send thus causing the engine to die.

DeleriousZ · 02-20-2007, 07:34 PM

no, it sends it into limp mode and shouldn't rev above 2200rpm...

k3smostwanted · 02-20-2007, 11:27 PM

Quote:

Originally Posted by DeleriousZ

no, it sends it into limp mode and shouldn't rev above 2200rpm...

Not on the Z32. At least mine never did. My car died. If it isn't reading the correct voltages it will go into limp mode but if mine wasn't connected it would die.

Regardless, something isn't right. with the MAF disconnected, the car should either not run or not rev past 2200rpms. by saying it runs better with the MAF disconnected, you mean it idles better? or it drives better, the car revs fine, etc?

Alphamalez32 · 02-21-2007, 07:51 PM

The car idles better wihout the MAF connected. It also runs but the rev doesn't go over around 2400. I had a used MAF in there that when i plugged it the car would shut down unless i accelerated a litle and kept my foot on the gas. when i had the used maf on the car does pass the 2500 but the car shakes and chokes, it also will have the tranny shift crazy. i have a small video that shows the car without the Maf idle, but dont know how to put it online.

k3smostwanted · 02-22-2007, 12:14 AM

Quote:

Originally Posted by Alphamalez32

The car idles better wihout the MAF connected. It also runs but the rev doesn't go over around 2400. I had a used MAF in there that when i plugged it the car would shut down unless i accelerated a litle and kept my foot on the gas. when i had the used maf on the car does pass the 2500 but the car shakes and chokes, it also will have the tranny shift crazy. i have a small video that shows the car without the Maf idle, but dont know how to put it online.

hmm....would lead me to believe that the MAF you are using is faulty but they are pretty expensive to go around replacing without knowing for sure. it seems that it would be the culprit though...

SaucyTabasco · 03-16-2007, 02:09 AM

Something similar happened to me before...

I haven't personally looked down the barrel of a 300zx MAF sensor, but if it is anything like one on an Isuzu rodeo I know something that may help. On my rodeo it messed up after I installed a K&N filter, apparently the oil from the brand new filter had fallen back to the MAF sensor and coated the little wires...so I went and bought some electrical sensor cleaner ($2) and some cue-tips ($1), got the thing out, sprayed the 3 fine wires and the 3 sensors inside the MAF housing, sprayed down the cue tips (you dont want fuzz left behind) and rubbed them softly. Had to do this a few times on each, a black/brown residue has coated them and easily came off. DO NOT *SCRUB*, BE VERY GENTLE! These sensors are really sensitive, treat them as such...new MAF sensors are $$$ also, so keep that in mind. Has worked great ever since...OBD codes dissappeared as well as hesitation, etc.

As stated, I didn't look at the MAF inside when I was putting my K&N on my Z, but it is probably similar. Try this before going to buy a new MAF!

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