throttled problem.. car jerks whilst keeing cruising speed

[FullFlxd]

Hey guys Im having a little trouble with the go pedal....

Whilst cruising at 90 or 100 the car seems to jerk abit as if im not pressing the accelerator hard enough but if I push it harder I gain speed. However, if I set cruise control its fine.

I havnt checked yet but im assuming the 09 GU's are running a sensor to measure throttle position?

Anybody else have this problem or have any advise??

[Bigrig]

Yep, check if you have a TPS mate and if so, disconnect the plug, get a multi meter and put the positive lead on the centre pin and the negative on either of the outside pins (one is the sender and one is earth, so try both to get the right result). Whilst connected, have the meter set to resistance (ohms - 20k) and open the throttle slowly whilst watching the meter itself - it should be a smooth climb up and down in resistance - if you notice a spot where it is erratic or spikes/drops etc, then the TPS is needing replacing ...

Hopefully it's that easy for you mate and you get it sorted!!

[Dhuck]

Welcome to the forum mate. Hope the info above helps. But could you head on over to the introductions section and say gidday.

[Bigrig]

Yep - missed that, thanks Dhuck!

As said mate, pop over to the intro section and let us know a bit about yourself and your rig. No harm done, but something we ask for ...

Is your rig diesel or petrol?

[FullFlxd]

No worries.

Its a diesel

[grimace]

sorry to barge in but whats a TPS? mines doing the same thing but it dosn't matter how fast i am going and its down on power also using more fuel.

[Bigrig]

No worries.

Its a diesel

Not sure on what does it on a diesel to be honest mate - not TPS though ... hopefully one of the diesel boys can help out.

[Bigrig]

sorry to barge in but whats a TPS? mines doing the same thing but it dosn't matter how fast i am going and its down on power also using more fuel.

Is it petrol? TPS is the throttle position sensor on the throttle body. Measures how "open" the throttle butterfly is relative to vehicle speed and accelerator input and plays a big part in sorting your gear changes on an auto (amongst other things). Is used by the ECU and TCU (if auto) in determining throttle input.

Apart from that, others may have more technical/mechanical input on its role mate.

[grimace]

mines the 3L commonrail

[FullFlxd]

OK if CRD's dont have a TPS what the hell is the problem?? mines stopped again. Grimace I did feel losses in power a couple of times, but my fuel consumption got better. Its taking the p!ss now I've posted this question in other forums and havnt even got a reply!! but Im leaning to the accelerator pedal cause there isnt nothing else left, I still havnt had a chance to play with it though

[Bigrig]

C'mon diesel boys and girls - a good problem to sink the teeth into and help old mate out of some bother. Know very little of the diesels, but would be surprised if one of the more mechanically minded on here haven't heard of something similar.

Hang tight mate - no doubt someone will be along to assist!!

[DX grunt]

I'm probably totally wrong here, but could it be dirty fuel, filter or tank?

Edit: I've also been told that there are different 'grades' of diesel at different times of year, ie a 'summer blend' and a 'winter blend'. Don't know how true that is.

[patch697]

Im not 100% on this but I do believe the 09's were fly by wire (electrically controlled go peddle not cable like earlier models)

If thats the case & given the info you provided I'd be looking closely at your peddle actuator as the sours of your problem.

If I am correct in what I say, replacing this "should" see you all sorted, but without seeing the Rig its only an educated guess.

[Yendor]

I would have a chat to Nissan first, it could just be a software issue that needs reprogramming.

Is the vehicle still in warranty?

What mods have been done? egr blocked?

[Maxhead]

Im not 100% on this but I do believe the 09's were fly by wire (electrically controlled go peddle not cable like earlier models)

If thats the case & given the info you provided I'd be looking closely at your peddle actuator as the sours of your problem.

If I am correct in what I say, replacing this "should" see you all sorted, but without seeing the Rig its only an educated guess.

I think all CRD's have a electronic controlled throttle. I've heard of a few having this issue and a good spray with contact cleaner should sort this put. Pull the TPS out and soak the insides with contact cleaner and give it a shot.

[FullFlxd]

Just came off warranty and Nissan said they couldnt duplicate the problem and didnt touch the car even when asked to check various things.

It's actually stopped doing it a couple of days ago, nothing has changed fueled up at same servo and same pump as the a week or two ago, I'll peek into the accelerator actuator one day this week.

Cheers fellas, great help.

[FullFlxd]

Sorry no mods as I had problems at end of last year with the car and wanted to wait till it was all sorted till I start mucking about. I was at the point where I didnt want them blaming bigger tyres for something you know.

[WhiteGU]

Just came off warranty and Nissan said they couldnt duplicate the problem and didnt touch the car even when asked to check various things.

It's actually stopped doing it a couple of days ago, nothing has changed fueled up at same servo and same pump as the a week or two ago, I'll peek into the accelerator actuator one day this week.

Cheers fellas, great help.


Sounds like you may have answered your own question, so to speak.

New fill of fuel, problem gone.

A friend got a dose of petrol laden diesel fuel from a metropolitan Safeway servo last week. Fortunately he only topped up half a tank, so it was pretty diluted.

[FullFlxd]

Sounds like you may have answered your own question, so to speak.

New fill of fuel, problem gone.

A friend got a dose of petrol laden diesel fuel from a metropolitan Safeway servo last week. Fortunately he only topped up half a tank, so it was pretty diluted.

No unfortunatley that isnt the case cause I have filled up before thinking that it would help and it didnt go away. last service Nissan had told me the lines were clear and the filters were clean , not much sign of water. But I believe them as much as I like the semll of fish.

Untill it happens again im not going to be able to test what it could be. So I'll save sprayin any contact cleaner till that time.

Also if it was the fuel it would happen when I switched the cruise control on but it doesn't
Cheers for all your help though

[mick20]

I had the same problem on my 2008 GU ST (CRD).

My cousin gave me some advice so I removed my intercooler and sprayed it with degreaser and gave it a good wash out then blew it out with an air compressor and left it to dry in the sun (standing on a bench seat with the outlet at the bottom for excess water to drain) for a few hours (give it a shake every now and then to get any other excess water out).

I also took off all the hoses that were attached to the intercooler (on both sides) all the way to the MAF sensor and sprayed them with degreaser and cleaned them out (some had a bit of oil in them). I also cleaned the MAF sensor and turbo inlet (sprayed them with carby cleaner) when spraying the turbo fan - put a rag under the inlet pipe and in front as you will be surprised how much gunk comes out (this cleans the blades apparently), after putting it back together I have not experienced the surging problem since. (Just got the coolant leak from the timing cover problem?)

[FullFlxd]

IThanks for your input guys have recieved some good ideas compared to other forums!!! I still havent had time to look at it too much other things to do. I've noticed its happening more often now during a few gears but only when gently accelerating, but cruise helps it out. I'll get to it soon.

[Robo]

Description ONLY for petrol EFI.

TPS, MAF and a faulty O2 sensor, can cause engine surge.
TPS electronic fault diagnose as described by Bigrig on p1.

Yep, check if you have a TPS mate and if so, disconnect the plug, get a multi meter and put the positive lead on the centre pin and the negative on either of the outside pins (one is the sender and one is earth, so try both to get the right result). Whilst connected, have the meter set to resistance (ohms - 20k) and open the throttle slowly whilst watching the meter itself - it should be a smooth climb up and down in resistance - if you notice a spot where it is erratic or spikes/drops etc, then the TPS is needing replacing ...

MAF also can be checked as per manual diagnose. YNOT, Tony explained this one elsewhere.
And cleaned with CRC, MAF spray cleaner.

O2 sensor recommended changed every 80 000k ( from memory Bosch site ).
can cause engine to surge as signal from it causes ecm to vary fuel ratio, cycles rich lean.
wear out or become clogged up and can't tell how much O2 oxygen in exhaust.
O2 sensors vary in quality, good idea to go with name brand like Bosch or Nippon for instance.
they will be more expensive but quality always cost.

cheers