Ok here is the story. I recently dropped the transaxle to replace the flywheel, due to breaking teeth off while installing my UDP pulley. I put the transaxle back in and fired the car up, it ran like a champ, idled was perfect, probably due to cleaning the throttle body while I had easy access to it. I checked the tranny fluid and took it for a test drive. I ran fine for about 5 minutes, and then it began to hesitate a little. I felt surges forward every couple seconds, but if I gave it a little more gas and kicked up the RPMs it was fine. It finally through a couple codes, P0300 - "Mulitple Cylinder Misfire" and P1320 "Ignition Signal." It only seems to miss when the car is in drive, if the car is sitting at idle and you rev it a little it doesn't miss at all. I'm at a total loss....The only thing connecting the transaxle and the ignition system would be the crank position sensor counting the signal plate teeth. I've heard of bad things happening when your flywheel becomes magnetized, but could this cause it? I didn't touch the flywheel with any magnetic tools, but who knows if anyone else did prior to my receiving it. Is there any other sensors connecting the transaxle and the ignition system? And if some of my coils are going out wouldn't they miss whether it was in park or drive? Any help would be greatly appreciated....Thanks so much.
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(
You've removed and cleaned the crank position sensor in case of contaminantion?
Which one? I cleaned the POS on the trans prior to placing it back into the vehicle, but I will check it again tonight to be sure. I've heard that magnetizing the flywheel is bad, but how would I know if that was the case? And if it was, how the hell would you demagnetize it?
I'm going to replace the fuel filter tonight and pull the fuel pump out and check the little filter there for contaminants as well. I've been working on this car for a month and a half now, it seems everytime I get one thing fixed something else appears. =(
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(
Well $236 tune up later and the problem is still there, no better no worse. The shop seems to say the same thing as I see on other posts, you need to replace all of the ignition coils. Yet they can't tell me which ones would be going out. It just doesn't make sense, it ran fine before I removed the tranny and replaced the flywheel. And it only misfires when it's in gear and moving down the road, sitting in the driveway in park it idles nice and smooth. Would an ignition coil only miss when in gear? Does placing it in gear change the load level? It doesn't make any damn sense.
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(
the coils may be bad, but they don't suddenly start to fail after the car sits for a month.
I'd look more into the crank sensor on the transmission, as brian said.
I did a clutch job on a 98 the other day and forgot to plug that guy in.. after abotu 30 sec of cranking I remembered, and plugged it in. voila! started right up!
If that sensor is giving out bad signals because it's dirty or something like that, then it can cause the engine to run poorly. I'd pull it out and clean it up and see what happens. it at least won't cost you anything and takes a whole 10 minutes.
Well I've replaced all of the coils, spark plugs, and fuel filter. I also cleaned and inspected both the grounds on the top side of the motor and the transmision. I took the throttle body off and cleaned it to as good as new and checked the MAF sensor (it was good). And the car still registers a random misfire. It seems to run just fine as idle and I have tried disconnecting each coil, one at a time, to make sure that the engine drops when each coil is disconnected and it does. Which means they fire just fine at idle, but as soon as you put it in gear and drive down the road it hesitates and misfires, surging forward every now and then. This car is really beginning to piss me off. Does anyone have any suggestions at this point? I have been to 3 mechanics and not one of them knows what the hell is going on.
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(
I tried this, put it in Drive, put the e-brake on, then check the coils. this didnt solve my problem though. what you have to do is wait til it misfires in drive with ebrake on, the disconnect them one at a time. problem is that mine doesnt misfire continually when in drive. you can definitely tell a difference between 1 coil misfire and 2 misfiring. if its misfiring, you disconnect one, and it is still misfiring only one, then you know that one you disconnected is bad. if it is misfiring and you disconnect one and it acts like it is about to shut off meaning only 4 are firing at that time, then that one coil is good because it made the misfire worse, at least for that test it is. sometimes i can get it to misfire in reverse with ebrake on better than drive. i also have the notion that the injectors could be acting stupid, but they are all clicking, and well, i really dont want to think an injector under the intake is bad since it is such pain to take off the intake manifold.
those are the 4 things required for a gas engine to fire.
fuel = injectors, fuel filter, fuel pump
air = MAF, air filter
spark = spark plugs, coilpacks, coilpack harness, wherever coils get signal to fire????????
compression = dont even want to think about it.
problem here is too many sensors.
there is the throttle position sensor which basically is an idle adjust, there are certain resistances and ohms that this should be within tolerance of.
and a camshaft or crankshaft postiton sensor, same thing. is this different from the throttle postion sensor?????
we will both get to the bottom of this 97Taxima and both be 4th gen max engine specialists.!!!! keep me up to date. i can only work on mine after dark since it is 100 degrees in the shade in alabama.
and a camshaft or crankshaft postiton sensor, same thing. is this different from the throttle postion sensor?????
All three are different. Check the factory service manual. You have a cam phase sensor that reads marks off the cam gear, a crank position sensor that reads off of the crank pulley, and another crank position sensor that reads off of the flywheel. All three are required, as is the TPS. The throttle position sensor reads how much the throttle plate is open/closed.
The only thing I can think of at this point is that the used flywheel I put in it my have been magnetized somehow....I have heard that this can cause a problem for the sensor, but can anyone tell me what the symptoms would be? Every manual mentions this problem, but no symptoms or how to even check it.......This is getting pretty frustrating. I was told my knock sensor was going out, would this cause the problem? The shop didn't seem to think so, but then again I don't always trust the damn mechanics.
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(
I tested my Crank Position Sensor on the flywheel last night, along with other various sensors. Everything tested ok but the CPS, it shows in the shop manual as a 5V signal when a screw driver is touched to the sensor, but my sensor is barely putting out 1V. I'm crossing my fingers that this sensor is my problem. I'm going to replace it this weekend so I will let everyone know if that is the culprit. I sure as hell hope so, I'm ready to start driving this damn thing.
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(
my 97 max misfires on the #2 cylinder no matter what i do. I changed out the coils and spark plugs, injector has correct resistance tolerance and it clicks while running as it should. changed #2 with #4 right beside it and #2 misfires still. checked cam sensor and both crank sensors, all within resistance tolerance. maybe it could be the last leg of the harness that connects cylinder #2 but all of the connectors are getting 11.94 volts so it isnt a power issue. all connections are clean too. im not spending anymore money until i know exactly what the problem is. maybe it is the ECM. something logical with 1's and 0's has to be messing it up. or could it be the cylider pressure? pleeeeeeaaaaase help me. im tired of feeling like im riding a bull when im driving around town.
well when i have the car running and in park and pull out the coil that always misfires it is sparking good, put it in drive with e-brake on and no spark, or in frist or second gear, no spark. sparks good in neutral and reverse. has to be an issue with tranny if it only sparks in certain gears. thats the crank position sensor (POS) on the tranny. i still have to back probe mine, all other tests were good though.
also, my oil sending sensor connector on the oil pan that sense oil pressure is just about shattered. does anyone know where i can get just the connector?
I have the same identical problem as above still....If it's at idle it is just fine same with reverse and neutral, but as soon as it is put in drive it hesitates and misses.....I tried changing both the crank sensors and there was no change. I took both of those sensors back and traded for an EGR valve and put it on....still no change. I have put on new coils, new spark plugs, checked all of the injectors, put on a new fuel filter, and cleaned and reattacheded all of the engine grounds.....If I ever do find out what the hell is wrong this car should run like a champ since everything has been gone through....I'm sooooo frustrated at this point. This sucks.
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1997 Nissan Maxima SE - Which I acquired for a MERE $700.
Red Maroon Metallic - With every option except heated leather..... =(