The other plugs either side of the NPS switch are the reverse light switch and 4x4 indicator switch. I can't find anything to say which is which. The cruise control is the likely culprit as it taps into the throttle position sensor, either at the pedal or the ECU. Your not susposed to remove the TPS switch from the pedal as it throws out the calibration, thats why they don't sell it seperately. If you want to PM me your address i can send down a pedal assembly for you to try.
D22 ZD30 Throttle cutting out / Intro
- Thread starter scottm
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charlie strayarc
Member
I cant find anything to say which switch is which either, but im guessing either your 4x4 light on dash or your reverse lights were not working previous to fixing up that broken wire.
Anyway heres hoping its either the cruise control or the TPS, because after that the only suggestion ive got is start learning about the electronic control unit part of the injection pump.
Just as a matter of interest how many kms on it and how long did you have it before these problems surfaced? Did these problems start after the fuel filter was changed as part of that big service?
Anyway heres hoping its either the cruise control or the TPS, because after that the only suggestion ive got is start learning about the electronic control unit part of the injection pump.
Just as a matter of interest how many kms on it and how long did you have it before these problems surfaced? Did these problems start after the fuel filter was changed as part of that big service?
scottm
Member
Hi again Rumpig,
I'm 90% sure it must be the reverse light because the 4x4 indicator light (little green car) has definitely come on when I've had it in 4wd.
I tried just unplugging the Cruise Control boxes from the loom and now the throttle doesn't seem to work at all (although it could just be my problem has gotten worsE) so I'll have to poke around (maybe contact auscruise directly) to see how to properly remove it.
Thanks so much for offering to lend me the pedal, I'll pm my address now. Much appreciated!
scottm
Member
Hi Charlie,
As above it seems the other sensor was reversing light as I've definitely seen the 4x4 light on the dash (I'll go and confirm in a few minutes).
It's got 148,000 km's on it (it had 143k when I picked it up couple of months ago), it has done it ever since I picked it up although it has gotten much worse. So in my mind original problem nothing to do with the service but potentially I could have made it worse somehow?
Thanks again for all your advice, will toil away and hopefully have it fixed as I need it for work tomorrow and right now it's not drivable :S
baitfish
Member
Hey Scott,
Mate if you can test a TPS with a new one, like Rumpig offered that will eliminate it completely. If you cant get your hands on one to test with you can test the voltages coming out of the tps with a multimeter. Its 0-5vdc signal. i'll have a look around in the manual and find the pin out so you can find what wires to test.
The other thing of interest from reading your post is that with the Cruise control disconnected you get no throttle at all? to me that sounds like, rather than the cruise control just tapping into your TPS circuit it actually breaks the circuit. I'd try test for continuity from the tps plug through to the ECU with the cruise control disconnected and then connected.
The plugs on the TPS can be a proper bitch to get off, but as Rumpig said i wouldnt go taking the TPS off the throttle. it can be a pain in the ass to set back up again. i took mine off and it took me a bit to get it all sitting right again. I then had to use ecutalk to reset the calibration of the throttle.
i'll see if i can find a pin out for you today mate.
Mate if you can test a TPS with a new one, like Rumpig offered that will eliminate it completely. If you cant get your hands on one to test with you can test the voltages coming out of the tps with a multimeter. Its 0-5vdc signal. i'll have a look around in the manual and find the pin out so you can find what wires to test.
The other thing of interest from reading your post is that with the Cruise control disconnected you get no throttle at all? to me that sounds like, rather than the cruise control just tapping into your TPS circuit it actually breaks the circuit. I'd try test for continuity from the tps plug through to the ECU with the cruise control disconnected and then connected.
The plugs on the TPS can be a proper bitch to get off, but as Rumpig said i wouldnt go taking the TPS off the throttle. it can be a pain in the ass to set back up again. i took mine off and it took me a bit to get it all sitting right again. I then had to use ecutalk to reset the calibration of the throttle.
i'll see if i can find a pin out for you today mate.
scottm
Member
Hi Baitfish,
Thanks for your reply. The no throttle without Cruise Control plugged in was a red herring. I've just unplugged both boxes Cruise Control + Electronic Actuator (whatever that means) and throttle is working. It's actually much more sensitive now.. ie: If I lightly rest my foot on the accelerator pedal it starts to rev, whereas before I actually needed to start pushing in with my foot and engaging the spring before it would start to rev. Just for shits and giggles I've left the cruise control boxes unplugged and doing a TPS relearn.
The super annoying part is that this morning I was just checking all the wires etc to the aftermarket cruise control etc under dash and found a wire (no idea what it does) that seemed to be hanging on by a few threads so secured it and took car for a drive. Went around the block and it was fine (yesterday it was crapping out like clock work just going around the block) took it down the road, did some high speeds and then about 8km's from home I quickly pressed on throttle when going from 3rd to 4th and it crapped out (and then actually stalled). Waited a while, car started fine. I then totally disconnected the wire I'd just secured (to be sure it had nothing to do with it) and the throttle worked perfectly. So that rules out that little wire.
I got the TPS plugs off by disconnecting the whole pedal (two screws internally and one screw on other side of firewall) I could get to the little plastic bits that you squeeze in and they came off easy.
The fact the TPS is not supposed to come off the pedal would explain why the screws were impossible to get out (even after a soak in wd40 I couldn't turn them)....
As for the TPS test for the 0-5vdc signal, would it be a way to test it while it's not actually having the problem? Or would I need to have the multimeter connected to the correct pins and keep pressing the accelerator until it does it before I'd know if that was the problem?
I'm beginning to think that the weather / temperature has something to do with this, because the other day when I was trying to go to work and had to return home in 2nd / idling it was freezing cold, and yesterday when I was working on the car trying to fix this problem it was barely getting out of my street before it would fail (again it was bloody cold yesterday). Today it's hardly doing it and it's much warmer...
Can anybody think of what would cause these symptoms more frequently in cold?
Getting totally pissed with this thing... If I'm not closer in the next couple of hours going to take it to the auto elec.
Cheers,
-Scott
scottm
Member
Auto Electricians
I've run out of time and really need the car for work the rest of the week so have taken it to the auto electrician's, car was crapping out all the way there (stalled completely 3 time had to sit and wait a minute and then nurse it again).
Thankfully was able to show the auto electrician the exact symptoms while it was happening which was at least something.
So annoyed.
Thanks to everybody for your help, I'll let you know the outcome.
I've run out of time and really need the car for work the rest of the week so have taken it to the auto electrician's, car was crapping out all the way there (stalled completely 3 time had to sit and wait a minute and then nurse it again).
Thankfully was able to show the auto electrician the exact symptoms while it was happening which was at least something.
So annoyed.
Thanks to everybody for your help, I'll let you know the outcome.
baitfish
Member
sorry i didn't get back to you in time mate. hopefully its not to costly to fix! let us know what the auto elecky says.
scottm
Member
No worries at all, frankly I wouldn't have been confident in my ability to test it accurately anyway (knowing which way around the connector is for the pin count etc).
Thanks heaps anyway, will definitely let you know how it goes.
scottm
Member
Auto elec - inconclusive
Hi all,
Latest update - got the car back from the auto elec. So the throttle was crapping out like clockwork when I arrived and was able to show the auto elec the exact problem, which he experienced for himself during a test drive. But he could not get it to do it again with the diagnostic equipment attached.
They re-earthed the earth strap (don't know if they replaced but definitely cleaned it up) and it hasn't faulted since. This was based on a thread I found here http://www.patrol4x4.com/forum/nissan-patrol-gu-gr-10/3-0l-engine-cut-out-while-cruise-22607/
I'm not convinced that has actually fixed it but I'll drive it for a while and see what happens. Auto elec was convinced that if that didn't fix it, it would have to be the Throttle Position Sensor as it's the only moving part that is subject to wear (this doesn't fill me with confidence but to be fair the car did fault without the cruise control plugged in ie: the two control boxes not plugged in but the wiring circuit still connected). I'll see if Rumpig is stil happy to lend me his in case it happens again and then do what I can to pick up a cheap one.
Will will report back after I've driven it around for a week. If anybody has any bright ideas in the meantime please let me know
Hi all,
Latest update - got the car back from the auto elec. So the throttle was crapping out like clockwork when I arrived and was able to show the auto elec the exact problem, which he experienced for himself during a test drive. But he could not get it to do it again with the diagnostic equipment attached.
They re-earthed the earth strap (don't know if they replaced but definitely cleaned it up) and it hasn't faulted since. This was based on a thread I found here http://www.patrol4x4.com/forum/nissan-patrol-gu-gr-10/3-0l-engine-cut-out-while-cruise-22607/
I'm not convinced that has actually fixed it but I'll drive it for a while and see what happens. Auto elec was convinced that if that didn't fix it, it would have to be the Throttle Position Sensor as it's the only moving part that is subject to wear (this doesn't fill me with confidence but to be fair the car did fault without the cruise control plugged in ie: the two control boxes not plugged in but the wiring circuit still connected). I'll see if Rumpig is stil happy to lend me his in case it happens again and then do what I can to pick up a cheap one.
Will will report back after I've driven it around for a week. If anybody has any bright ideas in the meantime please let me know
charlie strayarc
Member
Thats good news, fingers crossed its just the earth strap.
The fact the nps was unplugged makes me suspect a previous owner has chased this gremlin, and maybe had it diagnosed as injection pump and this could have been reason enough to offload vehicle.
If the problem persists and anyone tells you its injection pump, read the links posted by rumpig about ecu unit on top of pump before deciding a course of action. I would post the links but im on phone and 1000km away from my computer.
Keep us updated, this is all grist for the mill of navara knowledge.
The fact the nps was unplugged makes me suspect a previous owner has chased this gremlin, and maybe had it diagnosed as injection pump and this could have been reason enough to offload vehicle.
If the problem persists and anyone tells you its injection pump, read the links posted by rumpig about ecu unit on top of pump before deciding a course of action. I would post the links but im on phone and 1000km away from my computer.
Keep us updated, this is all grist for the mill of navara knowledge.
scottm
Member
Looks like problem is fixed
Hi all,
Quick update, sine the auto elec cleaned / re-wired the earth I haven't had a problem (has driven it roughly 500km's) so I'm pretty comfortable saying that the problem is fixed.
I'll post back in next couple of days of pictures of the earth strap.
Thanks to everybody for help and suggestions, really appreciate it, hope I can give back in the same way.
Cheers,
Scott
Hi all,
Quick update, sine the auto elec cleaned / re-wired the earth I haven't had a problem (has driven it roughly 500km's) so I'm pretty comfortable saying that the problem is fixed.
I'll post back in next couple of days of pictures of the earth strap.
Thanks to everybody for help and suggestions, really appreciate it, hope I can give back in the same way.
Cheers,
Scott
scottm
Member
help please
Spewing....
After 2 months this problem has reared it's extremely ugly head again happened first about a week ago and haven't driven it since....
For the life of me I can't think what I could have done to cause it. I've added a turbo timer and autron gauges but that was a month ago. The problem does seem to have come about after I fitted the plastic / dash back together (just hadn't gotten around to putting it back) but I've checked to see if any wires have caught on anything etc, taken all the plastics back off and it's still doing it.
I actually re-crimped the earth from the cruise control module (as when the auto elec cleaned the earth strap / other earths problem went away) so I was thinking just check all the earths and clean them which I think I have and it's still doing it.
The most repeatable way of recreating the symptom (throttle cutting out even when foot is to the floor) is by pressing the throttle to the floor as quickly as possible.
I swapped the pedal / TPS out with the one Rumpig sent me and the problem seemed to be better (after a dozen presses it hadn't skipped a beat) but then it did it. I then swapped my original pedal / TPS back in (hoping that maybe the frequency of failing would increase) but it didn't. So it almost as if once the car warms up (even though it had only been running for 3-5 mins) it doesn't do it as frequently, which to me doesn't make sense because it seems electrical / pedal related.
I really hope somebody can help / suggest something.
Thanks in advance....
-Scott
Spewing....
After 2 months this problem has reared it's extremely ugly head again happened first about a week ago and haven't driven it since....
For the life of me I can't think what I could have done to cause it. I've added a turbo timer and autron gauges but that was a month ago. The problem does seem to have come about after I fitted the plastic / dash back together (just hadn't gotten around to putting it back) but I've checked to see if any wires have caught on anything etc, taken all the plastics back off and it's still doing it.
I actually re-crimped the earth from the cruise control module (as when the auto elec cleaned the earth strap / other earths problem went away) so I was thinking just check all the earths and clean them which I think I have and it's still doing it.
The most repeatable way of recreating the symptom (throttle cutting out even when foot is to the floor) is by pressing the throttle to the floor as quickly as possible.
I swapped the pedal / TPS out with the one Rumpig sent me and the problem seemed to be better (after a dozen presses it hadn't skipped a beat) but then it did it. I then swapped my original pedal / TPS back in (hoping that maybe the frequency of failing would increase) but it didn't. So it almost as if once the car warms up (even though it had only been running for 3-5 mins) it doesn't do it as frequently, which to me doesn't make sense because it seems electrical / pedal related.
I really hope somebody can help / suggest something.
Thanks in advance....
-Scott
Hi Scott,
I've read this entire thread and I'm wondering if you've tried the other end of the TPS cable - the ECU itself? I just wonder if the car had been dunked at some point and the connector to the ECU had some oxidisation or other debris in it?
Full throttle will do a few things to the car's systems,
1) Change the output of the TPS to maximum, so the connectors and wires from the pedal to the ECU are getting the most power transferred through them. This should be in the order of milliamps, but there's always the possibility that it's enough to change the state of an unstable connection.
2) In a CRD engine the fuel rail pressure is raised to the maximum for the current RPM. This will cause the fuel flow to increase as well, whcih will change the flow rate of fuel forward from and back to the tank. In a non-CRD engine the injector pulse durations are increased and fuel flow rates still rise in a similar fashion. If either system detects an overpressure situation it could cut the fuel.
3) MAPS output starts to rise dramatically. I doubt the rate of the rise is a trigger, but I'm wondering if it reaches a level that triggers an engine fault.
4) Power consumption of the ECU ought to rise as computational requirements for fuel mapping, sensor input etc etc all go to maximum.
I'm assuming there are no engine warning lights, which means there probably aren't any codes stored in the ECU.
I would first go to the ECU, unplug it and look at all of the connection tabs looking for blemishes, oxidisation etc. The age-old thing to do with copper/gold fingers in computer equipment is to get a soft white pencil eraser and rub the contacts clean. You could also use emery paper - 1200 grit is good, but don't do it often.
Also examine the cables coming from the ECU and look for the one that provides an earth (body connection). If 10A flows into the ECU from positive, 10A needs to be handled from the negative as well. Clean that earth connection - it's not an uncommon fault.
I've read this entire thread and I'm wondering if you've tried the other end of the TPS cable - the ECU itself? I just wonder if the car had been dunked at some point and the connector to the ECU had some oxidisation or other debris in it?
Full throttle will do a few things to the car's systems,
1) Change the output of the TPS to maximum, so the connectors and wires from the pedal to the ECU are getting the most power transferred through them. This should be in the order of milliamps, but there's always the possibility that it's enough to change the state of an unstable connection.
2) In a CRD engine the fuel rail pressure is raised to the maximum for the current RPM. This will cause the fuel flow to increase as well, whcih will change the flow rate of fuel forward from and back to the tank. In a non-CRD engine the injector pulse durations are increased and fuel flow rates still rise in a similar fashion. If either system detects an overpressure situation it could cut the fuel.
3) MAPS output starts to rise dramatically. I doubt the rate of the rise is a trigger, but I'm wondering if it reaches a level that triggers an engine fault.
4) Power consumption of the ECU ought to rise as computational requirements for fuel mapping, sensor input etc etc all go to maximum.
I'm assuming there are no engine warning lights, which means there probably aren't any codes stored in the ECU.
I would first go to the ECU, unplug it and look at all of the connection tabs looking for blemishes, oxidisation etc. The age-old thing to do with copper/gold fingers in computer equipment is to get a soft white pencil eraser and rub the contacts clean. You could also use emery paper - 1200 grit is good, but don't do it often.
Also examine the cables coming from the ECU and look for the one that provides an earth (body connection). If 10A flows into the ECU from positive, 10A needs to be handled from the negative as well. Clean that earth connection - it's not an uncommon fault.
Read the post in this thread by Kiwibacon, starting from post no.87.
When he fitted a chip he had the same problem and it turned out to be that the TPS wire he tapped into was sheilded and the tap was earthing it out. He replaced that section of wire which fixed his problem. Where your Cruise tapped in may have done the same thing.
http://www.nosmokenopoke.com/forum/showthread.php?4822-Turbocharging-a-YD22/page9
When he fitted a chip he had the same problem and it turned out to be that the TPS wire he tapped into was sheilded and the tap was earthing it out. He replaced that section of wire which fixed his problem. Where your Cruise tapped in may have done the same thing.
http://www.nosmokenopoke.com/forum/showthread.php?4822-Turbocharging-a-YD22/page9
scottm
Member
Thanks Rumpig!
Wowsers! Have read and and although I don't understand all the troubleshooting etc that he did (would your average auto elec even understand this?) I get the gist of it... Basically I'll go and trace all of the cables coming from the cruise control and make sure they are making good connections and are not tapped into a shielded cable and earthing it.
To make sure the shielded cable is not earthing - I just make sure that the shielding has been separated / gathered and then insulated from the actual core with tape or similar yes?
You coming to the muster? (could bring your pedal with me and shout you a beer/scotch/rum/whatever)
Cheers mate,
-Scott
scottm
Member
Thanks for the suggestions Tony and taking the time to explain to me what happens when foot goes flat to floor. Am I right in thinking that my 2002 D22 Navara is a pre-common rail diesel?
I have not gone anywhere near the ECU itself.
You're right, there are no engine lights or fault codes being stored in the ECU. (so the auto elec told me when he checked it)
I'll clean all of the connections to the ecu as suggested and check / find the earth. Would using electrical contact cleaner be ok / advisable as well as the emery paper / rubber?
Will also check cables that have been tapped into for earthing of shielding as Rumpig suggested and report back.
Many thanks again!
Electrical contact cleaner is good, I'd use the plastic eraser before the emery paper since that's quite abrasive and should be used as a last resort. If the other products aren't shifting gunk off, that's when the emery paper comes out - but lightly, and only enough to clean it.
Rumpig's suggestion is an excellent one: if there's a shielded wire and you're tapping in to the centre conductor, it only takes a single filament to cause problems. At the low power levels we're talking about, it'd never get enough energy to heat up and destroy itself (and therefore rectify the problem).
The ugly truth for shielded cables is that they can also do this if they're crushed. The news does get worse, too!
I went to the Central Coast some time back to visit someone from this forum who was having trouble with their car. Half the car's wiring worked, the other half was erratic. Sometimes it'd start, other times not.
Turned out that either Nissan - or a backyard repairer - had used a single solid core wire to provide power to ignition/accessories and lights. The wire from the battery to the ignition/accessories had broken inside its insulator but this break was not visible on the outside. I found it by testing power delivery at various points in the cable then running my fingers over the cable and trying to bend the cable slightly to see if there were any variations (looking for things like the break that I did find). I am not in favour of single-core wiring in mobile structures - motor homes, caravans, campers, cars or motorbikes. Because they're mobile, they move - not just forwards and backwards, but up and down on uneven surfaces. This shakes the wires - and single core becomes brittle and fractures. It's something else you might want to consider.
Rumpig's suggestion is an excellent one: if there's a shielded wire and you're tapping in to the centre conductor, it only takes a single filament to cause problems. At the low power levels we're talking about, it'd never get enough energy to heat up and destroy itself (and therefore rectify the problem).
The ugly truth for shielded cables is that they can also do this if they're crushed. The news does get worse, too!
I went to the Central Coast some time back to visit someone from this forum who was having trouble with their car. Half the car's wiring worked, the other half was erratic. Sometimes it'd start, other times not.
Turned out that either Nissan - or a backyard repairer - had used a single solid core wire to provide power to ignition/accessories and lights. The wire from the battery to the ignition/accessories had broken inside its insulator but this break was not visible on the outside. I found it by testing power delivery at various points in the cable then running my fingers over the cable and trying to bend the cable slightly to see if there were any variations (looking for things like the break that I did find). I am not in favour of single-core wiring in mobile structures - motor homes, caravans, campers, cars or motorbikes. Because they're mobile, they move - not just forwards and backwards, but up and down on uneven surfaces. This shakes the wires - and single core becomes brittle and fractures. It's something else you might want to consider.
