Page 1 of 2

Jerking / Hesitation / Surging

Posted: 17 Aug 2015 11:44
by AndriesS
Lately I’ve noticed the following, It’s on a 4.8 GL ( manual gearbox) with 225k on the clock
When accelerating at full throttle in low gears (1, 2nd ,3rd) I’ve noticed it’s as if the revs does a step increase on the revs (looking at rev counter) it’s almost as if there is a surging but you don’t really feel it , however at part throttle it feels like a surging, it’s not really a jerk sensation nor a hesitation / flat spot just a surging while the speed increases.

Except for the obvious – i.e. it’s either fuel or spark any more precise ideas ?
How many km’s does the 4.8s fuel injectors last?

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 12:53
by SCUBA Patrol
Does your patrol still have the CAT converter in? It might be blocked or partially blocked!

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 13:46
by Tinus lotz
Ek stem vir daai exhaust ....miskien moet jy gou by steves in boxburg draai......om te meet is om te weet... :salute:

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 13:48
by Tinus lotz
Graham het n pressure gauge wat hy op die kar sit om die feul pressure te check terwyl jy ry ....hoe lyk jou pomp??

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 13:57
by Wilkie
Check daai in-line fuel filter onder op die chassis,min mense ruil daai filter op n gereelde basis :mytwocents:

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 14:04
by AndriesS
My patrol does not have a cat, Anyone experienced a original exhaust getting blocked?

Something I forgot to mention the Patrol does seem to smell very rich at idle (even when its warmed up), I've recently replaced the fuel filter but will try again.

Replaced the air filter recently and the only only servicble items are the plugs, I've done them about 80k ago and repalced them back then with platinum ones and they are suppose to last at least a 100k.

My suspects
injectors starting to go
fuel pressure
MAF sensor - what is the tell tale sign of a MAF sensor starting to go?

Thanks

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 14:07
by Tinus lotz
Ruil daai plugs nissan verkoop nie eers meer daai the 100k plugs nie daai goed fail :thumbup:

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 14:13
by Wilkie
Tinus lotz wrote:Ruil daai plugs nissan verkoop nie eers meer daai the 100k plugs nie daai goed fail :thumbup:
Soos Tinus se ,daai vonk proppe vonk lankal nie meer soos hulle moet nie :thumbdown:

Re: Jerking / Hesitation / Surging

Posted: 17 Aug 2015 19:25
by Brett Bignoux
GOOD DAY Andries , your surging problem may be from a dirty MASS AIR FLOW SENSOR . I have the same problem with a Nissan 2.4 hi rider . I disconected all the loom plugs on the motor and sprayed them with Q20 . I then sprayed the air flow sensor venturi with carb cleaner . the surging has mostly dissapeared , but it seems I may have to give it another spray with carb cleaner down the venturi to clean it completly . I hope this helps you and others with the same problem . Now fix it and go enjoy the 4x4ing ! CHEERS FOR NOW !

Re: Jerking / Hesitation / Surging

Posted: 17 Oct 2015 06:46
by nick vc
Hi . I can't believe its been 10 months since last on this forum travelling from the cape up to Limpopo . The prob with my 30 grx 2001 then was jerking , power loss and high egt going up steep mountain passes esp between graaf reinett and cradock . I eventual ly went to Nissan bela bela and the mechanic simply bypassed a bunch if inline after market fuel filters that previous owners had installed for whatever reason .
And , whala , after all that missioning , she went and still drives like a dream !!! Even pushed her to 180kmp/h VERY BRIEFLY . She's a bit battered and scratched after 10 months hard labour in the bush but then is a work horse not a fashion model . Also pulls lots of inferior vehicles like cruisers out of trouble .
Regards to all
Nick