07 Nissan Versa acceleration issues

So I bought this car about a week ago, had a friend look it over and everything seemed fine. We both drove it, I was able to make a good deal on the car (or so I thought…), and we agreed on a time and place to switch everything over a few days later. I left work for a little bit to get that taken care of, it drove perfectly from the notary to my work, and then it sat for maybe 6 hours. When I went to leave work that evening I pulled out onto the road and suddenly had no acceleration so I managed to drift into the car wash that I was by. It was revving really low and barely creeping along but once I was able to pick up some speed, I did a few laps around the car wash and everything seemed fine so I drove home. Later that night I went to go out for a bit and the same thing, barely creeped along til I got going for a few minutes then it drove normally. The check engine light came on after I had gotten to my destination and started up the car again. It has been sitting at my house since and my friend that I had look at it can’t really figure out what the problem is.

When it is in park or neutral it revs up normally, but when it is in drive or reverse it’s very weak, kind of just bounces up and down between 1k-2k rpms. I haven’t taken it back out because I’m afraid it might not pick up again like it had before after getting it going a bit.

I’ve searched my problem and found a lot of people with the same thing saying that it is the throttle position sensor, and I’m really hoping it’s something like that and not a transmission. The alternator and battery are new. It doesn’t seem to have any power issues, it starts up and idles just fine, and nothing dims at all.

I also have the list of codes that he pulled with the OBD scanner- P1778 stepper motor/function
P1715 input pulley speed signal
P1574 automatic speed control device (ascd) vehicle speed sensor
P0720 output speed sensor circuit
P0746 pressure control solenoid a performance/stuck off
P1701 power supply circuit
P0615 starter relay
P1778 step motor/ function
P0868 transmission fluid pressure low

I was going to get a throttle position sensor just to see if that would fix the acceleration problem but he doesn’t think that’ll fix it Has anyone had a similar problem or have any idea on what the problem(s) are??

I really hope I didn’t get burned too bad on this :frowning:

This is because your car goes into limp mode.Replace the crankshaft position sensor and all will be good.

If you want a pinpoint diagnosis,you need diagrams and ability to to test certain circuits. A TPS can be also tested to some degree with a scanner. You may looking at an intermittent problem so testing needs to be done thoroughly. I believe in most cases a car will not start with a faulty crank sensor

$1k paperweight. after you find out what a new trans costs

Yeah I guess… Like I said it drove perfectly when we test drove it the day we went to see it and it had no check engine light on, and no codes came up. Also drove perfectly from the notary, still no check engine light or anything.

Please explain your reasoning, especially why you think the crankshaft position sensor is the culprit

The 4 trans codes kinda caught my eye.

They caught my eye, as well

And I’m really quite curious, as to why @COROLLAGUY1 thinks the crankshaft position sensor is the culprit

I’ve replaced many faulty crankshaft position sensors which generated no codes, but they always resulted in stalling and/or no starts

I’ve never had all the symptoms op described, and have the culprit in fact be the crankshaft position sensor

given all those codes, I’d be taking a closer look at the powers and grounds, inputs, outputs, etc. for the automatic transmission and its control module

Doesn’t sound like a throttle position sensor problem to me. If engine related, the symptoms are more like a cat or electrical system problem. Possibly a crank or cam sensor. The transmission related codes suggests there a problem there of some kind, but not necessarily serious. Here’s what I’d do first with those symptoms

  • Verify transmission fluid level is correct
  • Verify battery measures about 12.6 volts before first start of the day, then measures 13.5-15.5 volts after starting the engine, at idle, with lights and accessories off.

Explain more what happens when it “had no acceleration”. Do you mean you stepped on the gas and the engine seemed to speed up normally, but the car didn’t speed up? Or do you mean the engine didn’t speed up as you’d have expected?