Pajero 4WD Club of Victoria Public Forum Pajero 4WD Club of Victoria Public Forum

Go Back   Pajero 4WD Club of Victoria Public Forum > General Information > Fuel and fuel systems

Fuel and fuel systems Petrol vs Diesel, LPG Conversions, premium fuels, and all that gas

Reply
 
Thread Tools Display Modes
  #1  
Old 05-06-19
jeyare jeyare is offline
Junior Member
 
Join Date: Jun 2019
Location: SVK
Posts: 27
Default car hesitates to move when the gas pedal is pressed

Gents, here is my story.
My problem is based on unexpected “car hesitates to move when the gas pedal is pressed”.
Car – Pajero 3.2DiD 118kW V98W (180k km mileage)

It happened few times (past 2 weeks) during these situations:
– car stopped at lights (to be sure – no Neutral used)
– accelerator pedals pushed, engine RPMs increase to expected range (visually and noisy), no wrong sound
– but car really hesitates to move, speed about max. 5km/h
– several attempts to push the acc. pedal, no change the car speed still like turtle
– it spends 5-10sec and then (magic) car is back into normal operation.
No engine light, no ECU Fault code found.

Till today I found a Fault code: U1120 (by Torque Pro App). I found tons of U1120 dramatic stories, but just this one is logical:
U: OBD-II Diagnostic Network (U) Trouble Code For Engine
1: Fuel And Air Metering
1: Fuel Rail/System Pressure - Too High
2: Turbocharger Boost Sensor A Circuit Low
0: Shift Solenoid E Performance or Stuck Off
Need to measure.

Diagnostic of all measured values (till now) are in normal levels, but just during the normal car operation. Can send if it helps you. Because this situation (car hesitates to move) occurred randomly, no way to measure all the values during whole time of "normal" car operation.

Sometimes (randomly) I feel a delayed reaction of the engine from the acc. pedal. But still no Fault code or the Engine light.

Also checked EGR. No problem found.
But there is still “empty” fault code pool in the ECU.
How is your point?
Thanks.
Reply With Quote
  #2  
Old 06-06-19
jeyare jeyare is offline
Junior Member
 
Join Date: Jun 2019
Location: SVK
Posts: 27
Default

update:
- APP sensor checked APP. Both potentiometers provides same values, then no fault discovered. Of course, there is the ECM, that can detects the difference between both values and consequently will provide a APP Fault code. No wires damaged. Nothing.
- TPS sensor checked. Nothing.
- Throtlle plate checked. Nothing.
- EGR valve, this was my first intent to see, if there is some malfunction. Nothing.
Reply With Quote
  #3  
Old 06-06-19
old Jack's Avatar
old Jack old Jack is offline
Valued Member
 
Join Date: Jun 2011
Location: Adelaide
Posts: 6,855
Default

Auto or Manual transmission ?

Are any of the ASC lights illuminating ?

Have you tried driving with ASC selected OFF ?

Have you checked the correct operation and setting of the brake light switch ?

Do you left foot brake ?

OJ.
__________________
2011 PB Base White Auto, Smartbar, Cooper STMaxx LT235/85R-16,TPMS, HR TB, 3 x Bushskinz, front +40mm Dobinson , rear +50mm EHDVR Lovells, Dobinson MT struts and shockers, Peddars 5899 cone springs, Windcheater rack, GME UHF, Custom alloy drawer system inc. 30lt Engel & 2 x 30 AH LiFePo batteries + elec controls, Tailgate hi-lift/long struts, Nightbreaker +130LB & Phillips +100 HB, Lightforce 20" single row driving beam LED lightbar, Scanguage II.
MM4x4 Auto Mate, Serial No 1 .
Reply With Quote
  #4  
Old 06-06-19
jeyare jeyare is offline
Junior Member
 
Join Date: Jun 2019
Location: SVK
Posts: 27
Default

Quote:
Originally Posted by old Jack View Post
Auto or Manual transmission ?

Are any of the ASC lights illuminating ?

Have you tried driving with ASC selected OFF ? Snow mountains.

Have you checked the correct operation and setting of the brake light switch ?

Do you left foot brake ?

OJ.
AT
ASC ilumination - no
driving with ASC off - yes, 3M ago

Re Brakes:
Just to be sure:
- I have open another thread about possible issue in my HBB.
- or did you mean coorect operation and setup of brake lights switch only (no rest of brake environment)? I will check it the switch.

Re: left foot brake - yes, because A/T

Link to my HBB issue:
https://www2.pajeroclub.com.au/forum...ad.php?t=64435

Thx

Last edited by jeyare; 06-06-19 at 02:17 PM. Reason: update
Reply With Quote
  #5  
Old 06-06-19
old Jack's Avatar
old Jack old Jack is offline
Valued Member
 
Join Date: Jun 2011
Location: Adelaide
Posts: 6,855
Default

Quote:
Originally Posted by jeyare View Post
AT
ASC ilumination - no
driving with ASC off - yes, 3M ago

Re Brakes:
Just to be sure:
- I have open another thread about possible issue in my HBB.
- or did you mean coorect operation and setup of brake lights switch only (no rest of brake environment)? I will check it the switch.

Re: left foot brake - yes, because A/T

Link to my HBB issue:
https://www2.pajeroclub.com.au/forum...ad.php?t=64435

Thx

Try right foot braking and see if it still happens.
I am thinking there is a interlock that limits the amount of accelerator pedal movement that can be applied whilst the brakes are still on, hence my question about the adjustment of the brake light switch and its correct operation, particularly the OFF position, and also my question about left foot braking.


OJ.
__________________
2011 PB Base White Auto, Smartbar, Cooper STMaxx LT235/85R-16,TPMS, HR TB, 3 x Bushskinz, front +40mm Dobinson , rear +50mm EHDVR Lovells, Dobinson MT struts and shockers, Peddars 5899 cone springs, Windcheater rack, GME UHF, Custom alloy drawer system inc. 30lt Engel & 2 x 30 AH LiFePo batteries + elec controls, Tailgate hi-lift/long struts, Nightbreaker +130LB & Phillips +100 HB, Lightforce 20" single row driving beam LED lightbar, Scanguage II.
MM4x4 Auto Mate, Serial No 1 .
Reply With Quote
  #6  
Old 06-06-19
jeyare jeyare is offline
Junior Member
 
Join Date: Jun 2019
Location: SVK
Posts: 27
Default

Quote:
Originally Posted by old Jack View Post
Try right foot braking and see if it still happens.
I am thinking there is a interlock that limits the amount of accelerator pedal movement that can be applied whilst the brakes are still on, hence my question about the adjustment of the brake light switch and its correct operation, particularly the OFF position, and also my question about left foot braking.

OJ.
thx, for an idea. Result:
- there is no interlock mentioned
- no brake light switch issue discovered
- also for the brake pedal in OFF position, no findings.

Measured values from APP sensor in idle (no depressed pedal):
1st Potentiometer: 1016mV
2nd Potentiometer: 488mV (528mV diff)

then max pedal depressed (99,6% of measured range for both):
1st Potentiometer: 4668mV
2nd Potentiometer: 2324mV (2344mV diff) ... seems o be not linear difference

then little bit pedal depressed:
1st Potentiometer: 1406mV (7,0% of measured range)
2nd Potentiometer: 684mV (11,7% of measured range) and (722mV diff)
Reply With Quote
  #7  
Old 06-06-19
Nab Nab is offline
Valued Member
 
Join Date: Mar 2012
Location: Perth
Posts: 1,299
Default

Sounds more like a transmission or torque convertor issue. If the engine still revs up and sounds normal the car should still move normally.



I think there may be an issue with your throttle but that doesn't sound like it is causing no drive.
__________________
SOLD 2004 NP 3.2 auto
NOW 2014 Ranger XLT auto
Reply With Quote
  #8  
Old 06-06-19
jeyare jeyare is offline
Junior Member
 
Join Date: Jun 2019
Location: SVK
Posts: 27
Default

Quote:
Originally Posted by Nab View Post
Sounds more like a transmission or torque convertor issue. If the engine still revs up and sounds normal the car should still move normally.

I think there may be an issue with your throttle but that doesn't sound like it is causing no drive.
Thx for your point.
Torque converter seems to be a reason, but not for "randomly" discovered issue of hesitated car. Another point - for such source from the torque converter you have to listen clicking or a revving noise (as converter source indication). Nothing like this.

Second: bad torque converter will take the transmission longer to engage the engine, resulting in higher than normal stall speeds. I have different symptoms - I have revs but with sustained 5km/h speed (not stalled) till the miracle, when car is switching into normal (no foreign sounds there during the switch to normal).

Third: most common symptom for the converter is a shuddering. Nothing happened.

The Throttle - checked. Still 100% open.
Reply With Quote
  #9  
Old 07-06-19
4ePikanini's Avatar
4ePikanini 4ePikanini is offline
Valued Member
 
Join Date: Dec 2009
Location: South Africa, East London
Posts: 730
Default

Atf level should be your first check
If thats all good, double check tranny wiring and connectors

Your issue is likely atf level or valve chest (mechanical or electrical or wiring)

Sent from my S60 Lite using Tapatalk
__________________
1993 3.0 V6 Pajero - SOLD
2001 3.2 Di-D Pajero - SOLD
2005 Touareg R5 2.5 TDi - SOLD
2007 Pajero LWB 3.2 Di-D
Reply With Quote
  #10  
Old 07-06-19
old Jack's Avatar
old Jack old Jack is offline
Valued Member
 
Join Date: Jun 2011
Location: Adelaide
Posts: 6,855
Default

All the reported intermittent symptoms still point towards the brake switch is not releasing correctly so the AT ECU still thinks the brakes are applied.

The INVECS Adaptive Learning AT program has several built in self protection functions that limit engine power if the brakes are still applied (or the AT ECU is getting a signal that the brakes are still applied) and or the wheel speed is low compared to engine rpm. This is to protect the torque convertor from damage. Brake switch is a cheap and easy replacement so this would be my first action if I could not fault the switch or its adjustment.

Or there is some intermittent problem with the signal from the accelerator pedal but the OP has checked these and at the time of checking they were OK. The only way to exclude these are to either replace the sensors or wire in two digital voltmeters and monitor the voltage during normal and abnormal conditions.

OJ.
__________________
2011 PB Base White Auto, Smartbar, Cooper STMaxx LT235/85R-16,TPMS, HR TB, 3 x Bushskinz, front +40mm Dobinson , rear +50mm EHDVR Lovells, Dobinson MT struts and shockers, Peddars 5899 cone springs, Windcheater rack, GME UHF, Custom alloy drawer system inc. 30lt Engel & 2 x 30 AH LiFePo batteries + elec controls, Tailgate hi-lift/long struts, Nightbreaker +130LB & Phillips +100 HB, Lightforce 20" single row driving beam LED lightbar, Scanguage II.
MM4x4 Auto Mate, Serial No 1 .

Last edited by old Jack; 07-06-19 at 07:52 AM.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Time to move on Stroker Generation 3 Pajero 11 11-07-18 03:13 PM
A Move to Gen 4 gaz1 Generation 4-2 Pajero 3 01-07-17 08:57 PM
Still on the Move around Oz Thomo238 Trekking around Oz 3 08-09-13 08:43 AM
How to move gas bottles lenny05 General Info 17 08-01-12 07:26 PM
3.5 petrol hesitates at 25-30% load jc20b Generation 3 Pajero 6 19-12-11 08:19 PM


All times are GMT +10. The time now is 02:46 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.