car RPM moves up and down in acceleration
 

Hello everyone... i drive a 92 Maxima SE.. ( finally got it on the road ) and I will post up pics soon. Unfortunately the car is an automatic and when i shift from park to drive, the engine moves a good few inches which means the motor mounts needs replacing. Upon acceleration the engine kicks back and rpm moves from 4.ooo-2000 RPM over and over until i let go of the gas pedal and reaply pressure on the pedal again that the car operates normally. Just change my fuel filter so i dont think its that. Can this be from the motor mount? The person that i bought the car from stated to me that he has not change the timing belt yet. Can this be from the timing belt..or electrical, distributor and spark plugs...

I am lost and would like to fix this damn problem so i can start to do more with the car. Thanx for the help.

for one if you true have a SE macxima it dont have a timing belt or a distributor

but you proboly have a GXE with the sohc engine which has those components

i personally need a better description of the problem its alittle to vage for me to give suggestions for but first you need to conferm which model car you have because they have different engines that have different problems

I had the same problem on my 94 a while back. My engine rpms would bounce across the rpm range from 2k all the way to 4k and the car would not move. I would have to let off the gas and then give it gas again. It happened right after I did a JWT ECU swap. I sent back the ECU and had them give me another one. My car has been running like a champ ever since.
But like subs1000w said.......you don't have a timing chain if you have a true SE 'cause you would have the DOHC motor as opposed to the "wimpy" SOHC motor which has a timing belt. :hat:

actually i have the DOHC ( says it on my motor ). I read member " dorraj " 's thread and he has the same problem. His engine has the same power surges at low speed. To best describe it...it's like you hit the gas pedal and than let go and hit the gas and let go. I'm just wondering if my tranny beginning to go.

Clean your TB, check/change your plugs, and check your coils. I would also check the ECU for any codes. Mine did the same thing, turned out to be the fuel pump, which won't throw any codes, it will eventually just die.

Yeah, i've been having a similar problem lately with a sort of hesitation as i'm accelerating. Fuel pump might be worth a look.. FNG, can you please explain what your pump was doin? was it actually cutting out or just not providing enough pressure to keep the fuel up? Whats the reccomended pressure in the fuel lines supposed to be? i might get this checked. cheers mate.

My car was stalling when it was idling and under light acceleration, it would also do that weird surge every once in a while, where you hit the gas and it surges between 0 and whatever RPM it should be at until you let off and then accelerate again. It would start right up after it stalled. I occasionally had hard start issues in the morning too. This was all intermittant and happened on and off for 3 or 4 months. Last week, I pulled into my GF's Grandmothers driveway and shut the car off, 5 min. later I went to start it again and she would turn over, but not even try to run. Fuel pump was toast. I couldn't hear it prime, but I checked all of the relays and if there was power where there was supposed to be. I took the pump out and hooked it directly to the battery and it ran for half a second and died completely. I replaced it and she's been perfect since then. I'm pretty sure stock preassure is around 35-40 PSI.

hmm, doesn't sound like my problem, but thanks for the info! Might test my fuel pressure anyway, or maybe buy a fuel pressure gauge. Gauges are fun!

I forgot to mention that the car "power" button comes on intermintally when this happens. Spoke to a mechanic and he thinks its some kind of transmission sensor. The funny thing is that this only happens when the car is cold.

I have this same problem. I have a 1990 auto. It starts up great and then I put it into drive, I then ease the gas down a little to get her started and the rpms just drop and the car sounds like it is going to die but it doesn’t. What’s really sad is when the motor cold and its in drive and I have the brake on and I go to roll up 2 windows it bogs the motor down and it again sounds like it is going to die. So since it makes now power and sounds like it is going to die when I lightly press on the gas, I end up having to press pretty hard to get her to go when cold. I hate doing this on a cold motor as I end up getting up to 4k rpms. If I have time I let her worm up at idle but this can take some time. After the car is wormed up or I’m in the higher rpms (above 1200-1500) its fine. I think I might check the compression, anyone know what #s to look for on a motor with 155k miles.

Thanks

So nobody knows what compression #'s I should look for??? Also I might add most of my exhaust has rusted off so I don’t have much back pressure

tranny problem. that's the "check engine (ok tranny) light"

sounds like normal issue. I believed all of the VG engines comes with a rev limiter controller and it could only be changed by modifying your ECU board. If you could afford a Jim Wolf modified ECU, then I am sure you'll should be able to fix this problem in no time. Otherwise, I'd take it more seriously if you floor the gas pedal the acceleration needle refuses to respond. Then it could be lots of things.