Dead spot in the TPS? Weird power loss at 2-3k RPMs

[robomatic12]

I'm not sure if my TPS has a dead spot (I remember reading this in a thread before) or something else. If I'm cruising around 50-60km/hr which will normally be at around 2k in 4th gear the power will fall flat on its face but if I put my throttle pedal down I can see my boost/vacuum gauge going up but nothing happens and then bam a few seconds later all is normal. This has started to happen more and more. If I drop down a gear or increase the rpms its fine and it never does it at higher rpms. It feels like there is no fuel, like a fuel cut? Just crusing along.... wuuuhhhhhh no power... and then it comes alive again. Any thoughts?

*EDIT* also it bucks when it does this, this seems to be a common thing for TPS dead spots, anyone else experienced this?

[hacyec]

I was about to create a thread on this today, been happening for about a week now and getting more frequent for me. If you take your foot off the gas and put it down again, does the problem go away until you get to another gear? It happens to me on 2nd, 4th and 5th, rarely on 3rd though.

I've checked my codes and get a 55 and according to the ECU diagnostics on this page that means all is good, though the writing on the side of my ECU is in Japanese

http://www.ttzd.com/

Have you run your codes? Going to check my spark plugs next but since you mentioned the TPS, I'll clean that up as well.

[Zwicked]

It's easy to test the TPS with a multimeter and cycle it slowly while watching the multimeter and see if there are any dropouts along the way.

[robomatic12]

By dropouts: does the voltage go to zero or does it stop going down/up?

[Zwicked]

You can test it on the car just like you are going to set it, or take it off and set the multimeter to ohms and check resistance through the path.

On the car what I do is get a couple of sewing needles and push one into the gray connector beside where the red and white wires go in. That way nothing is damaged and you get a good connection. I made up a set of multimeter leads with alligator clips so they can clip to the needles. Turn on the ign and set the TPS to .45 volts with the throttle at rest. Now slowly open the throttle all the way. There should be a smooth progression up to about 4.5 or so volts. Easy to see if there are any dead spots.

After you are done, unplug the TPS connector while the ign is on for about 15 seconds and then plug it back in. That lets the ECU know it's new position as a starting point.

[jp-racing]

You can test it on the car just like you are going to set it, or take it off and set the multimeter to ohms and check resistance through the path.

On the car what I do is get a couple of sewing needles and push one into the gray connector beside where the red and white wires go in. That way nothing is damaged and you get a good connection. I made up a set of multimeter leads with alligator clips so they can clip to the needles. Turn on the ign and set the TPS to .45 volts with the throttle at rest. Now slowly open the throttle all the way. There should be a smooth progression up to about 4.5 or so volts. Easy to see if there are any dead spots.

After you are done, unplug the TPS connector while the ign is on for about 15 seconds and then plug it back in. That lets the ECU know it's new position as a starting point.

I have the same power loss and i am goin crazy, i all ready set my TPS like 10 time. I am going to order another TPS because if run my car with the TPS unplug it runs real strong with no problems at all, if i plug it back on and reset it the problem comes back. i set it at .45v when close and open is at 4.1v and this is on a sr blacktop TPS.

[pintovit]

My car did exactly that! I had to take the foot out of the accelerator and try again 2-3 seconds after... And it would go as nothing had happen.
Pedal to the metal and it would run fine. Also when I put it to neutral, it would idle (the engine didn't die, it just didn't accelerate).

Diagnosing the TPS it didn't seam to have any blind spots but it did replied with values in a different range of another TPS I bought.

So after switching the TPS, it ran perfectly.

So be very careful diagnosing and check if it is replying in the range of values it should (not only for the continuity between closed and open butterflies).

[robomatic12]

Yeah it ended up being the TPS, replacing it with an OEM unit from Nissan made the car much better to drive, and improved my gas mileage