Tps Filtering

[NYTSKY]

For as long as i can remember ive always had the slightest of hesitations when accelerating from very low rpm. Only very slight

Nothing that alot of people would notice but im very fussy when it comes to the tuning of my engine.

A few people i have talked to about it calls it the 'Haltech hesitation' and something that a few people have, but are not really fussed about.

Adam tells me he has to put a fair bit of filtering on the TPS when he tunes my car, would this be the source of the hesitation problem?

What would the symptoms of a failing TPS be?

[STATUS]

it can be as simple as a timing step just off idle or a lean or rich spot, fairly simple to locate (in a vacant carpark) and it is generally a bit of trial and error to smooth out. It took about 20mins of start stops testing to smooth a sr20 i did awhile back to the point it was imperceptible.

Laptop and a tps vs timing log would get you on the right track to start, when it jerks look for a jump in timing in the log, if there is nothing there start playing with the ms values in the inj map. If that fails look at the accel pump values. I often see too much fuel in accel pump which can also load up the engine so it stumbles.

[NYTSKY]

What would be the reason for the filter on the TPS?

[STATUS]

What would be the reason for the filter on the TPS?

To reduce noise, i have a funny feeling this was fixed in a firmware update by haltech. Try searching their forum as i swear i read something like this about a month ago.

[NYTSKY]

Funny you should say that, i have a custom update from Haltech in my E11 to try and smooth out the hesitation. Worked a little but still there.

I think we will just have to find a quiet spot somewhere and go through the motions to try and solve it.

I wish my knowledge of tuning was a bit better

[rob82]

I've seen the symptom on various windows based haltechs. Its an accellartion enrichment error that cannot be tuned out. Have seen the issue on constant throttle with acceleration enrichment turned off - if you scope it you will notice asyncronous pulses with a random amount of pulses and pulsewidths. Have sent the scoped data to haltech on two different cars - they havn't been able to sort the issue!

You will also notice that the pulses dont show up in the logs as an accelleration enrichment value.

[StealthX]

i get exactly the same problem with my x-trail...

im using an EMS stinger with a MAP sensor, and ive come to the conclusion its from 'noise' in the vacuum line to the MAP sensor.

im gonna try to put a filter/vacuum reservoir in the line see what that does.

Is your Haltech using a MAP sensor for the engine load? or is it throttle position?

i.e. are your sure its TPS related?

[STATUS]

i get exactly the same problem with my x-trail...

im using an EMS stinger with a MAP sensor, and ive come to the conclusion its from 'noise' in the vacuum line to the MAP sensor.

im gonna try to put a filter/vacuum reservoir in the line see what that does.

Is your Haltech using a MAP sensor for the engine load? or is it throttle position?

i.e. are your sure its TPS related?

if thats your only issue with the stinger you should be happy

[StealthX]

if thats your only issue with the stinger you should be happy tongue.gif

haha yeh no problems as yet.

needed a software update before i got it tuned, but apart from that, nothing!