Last Chance to solve the mystery

[jonela]

This is my last ditch attempt to solve the problem of the mystery fault before I let the car go for scrap. I am hoping there is someone on here that didn’t see the original post, or a new member who has some new ideas, or any new help as to how to trace the problem.
I have posted a link to the original post bellow but basically it’s this

Last year my 1997 T2 2.7Tdi S SWB Developed a problem with the tick over when you started the car it was fine, around 800pm. Once I set off, from then on the whenever I stopped the revs would drop to 500rpm almost stalling, after about 20 seconds the revs would pick up again back to 800ish.

I took it to the local Citroën dealer (the nearest Nissan dealer is an hour away) who couldn’t find the problem, but they rang the Nissan dealer and someone there said it was probably the injector pump
.
Any way while I was thinking about this one day after a good hours run, I stopped at a junction in our village and let the revs drop, then when it came to setting off, nothing happened when I pressed the accelerator, it just ticked over at 500ish. I was stuck in the middle of the road!

I had the car recovered by Citroen and they just said it’s the pump! Without doing any further investigation, and wanted 3000€ to replace it!

Now, as you will see from the original post I am not convinced with this diagnosis. I ether want to confirm this, or find the real fault. I have tried lots of things including changing the pedal for one I got from Clivvy. He also helped me to get a consult interface and the ECUTalk software, but I don’t understand any of the information this gives you, or how it will help find the fault.

Any help would be gratefully appreciated. I don’t want it to be broken up its too good and I want to do some mods to it when I get back to the UK and use it off road. Again any help gratefully appreciated
http://www.nissan4x4ownersclub.com/forum/showthread.php?t=18119

 

[Ogri]

Have you tried disconnecting the MAF and running without it? It can cause all sorts of problems if jiggered.

Worth a try?

Ian

 

[Lazy-Ferret]

Have you tried disconnecting the MAF and running without it? It can cause all sorts of problems if jiggered.

Worth a try?

Ian

I think that must depend on the MAF, if I disconnect mine, which is the Bosch 4 wire (but looks like it should have 5), when you put your foot on the accelerator, nothing happens at all...

Having said that, it does sound like it might be MAF related, as it sounds like it is going into limp mode. The only difference is, once in Limp mode, mine will not come back out, without stopping and restarting the engine.

 

[bry]

MAF or maybe Throttle sensor.

 

[tsteve4x4]

I think that must depend on the MAF, if I disconnect mine, which is the Bosch 4 wire (but looks like it should have 5), when you put your foot on the accelerator, nothing happens at all...

Having said that, it does sound like it might be MAF related, as it sounds like it is going into limp mode. The only difference is, once in Limp mode, mine will not come back out, without stopping and restarting the engine.

Mine used to do a similar thing, not quite the same but it would drop to idle and not rev up properly. At that time I just cleaned the MAF, Bosch type, with some electrical contact cleaner. It went fine for a few months until the MAF finally died and the car just drove as if was only on 60% power. I would borrow or beg a MAF from someone first to try. A quality Bosch one from Euro Parts is around £55 exchange.

 

[rustic]

You have replace the pedal.
I assume that you have also replaced the throttle position sensor, and you are certain that this is working ok.:nenau

Then Maf could be the way to go.

Are there any clues re any smoke, if so when and what colour?

 

[Banshee]

Any way while I was thinking about this one day after a good hours run, I stopped at a junction in our village and let the revs drop, then when it came to setting off, nothing happened when I pressed the accelerator, it just ticked over at 500ish. I was stuck in the middle of the road!

I had that before when I had disconnected my MAF

 

[davenclaire]

the maf has to be the first thing to try here but and its a big but i assume you have the electronic throttle fly by wire from the posts so the pump could be to blame their is a cold start sensor in it also the control sleeve may be out of alignement since replaceing my pump seals mine sometime judders and the revs drop off a bit because its not perfectly aligned. am still trying to plug my ecu talk into some one else tdi to read the throttle position sensor position so i can get mine perfect. rob on here has a 3.o l his had all the symtoms of fuel filter maf etc and it has proved to be the pump in the end, car now fixed with a replacement pump

pump timimg could be out dont scrap it im sure between us we can solve this give us some more infromation, any mil light ? check your codes what are they saying etc

 

[jonela]

Did the paperclip trick and it is showed two fault codes
13 Engine coolant sensor
43 Accelerator pedal position,this is why I changed the pedal
Engine coolant sensor was replaced 5000 miles ago as the needle hardly moved and I thought it was faulty after it was changed it was no different.
I have cleaned the maff with contact cleaner,but not replaced it

 

[davenclaire]

Did the paperclip trick and it is showed two fault codes
13 Engine coolant sensor
43 Accelerator pedal position,this is why I changed the pedal
Engine coolant sensor was replaced 5000 miles ago as the needle hardly moved and I thought it was faulty after it was changed it was no different.
I have cleaned the maff with contact cleaner,but not replaced it

engine coolant sensor wont cause your problem you have tried the pedal so lets dig deeper

1. have you replaced the fuel filter
2. have you removed the mini filter from the banjo bolt on the pump
3. have you fitted clear hoses to the fuel pump to check for air
4. is their smoke of any kind/ colour

 

[AlexD333]

Dont scrap it. You will kick yourself when its cured.

Running probelms can seem so daunting sometimes and seem like there is no end. :thumb2

 

[Ogri]

I have cleaned the maff with contact cleaner,but not replaced it

I see you have a 2000 2.7 also. If the Bosch numbers are the same you could try swapping one MAF for the other?

Sorry to keep harping on about the MAF but with there being no reaction at all to the throttle, it just feels electrical and very similar to an issue I had with my Renault that was cured with a MAF.

I'll shut up now...

Ian

 

[jonela]

The fuel filter was changed an system checked for leaks when trying to find the slow tick over problem. I seem to remember looking for the mini filter but seem to think it didn't have one (it's been a while now)
I think I will try swapping the the maf with the one on the 2000 I'm not sure if there the same I will look Tomorrow

 

[Banshee]

I have tried lots of things including changing the pedal for one I got from Clivvy. He also helped me to get a consult interface and the ECUTalk software, but I don’t understand any of the information this gives you, or how it will help find the fault.

Not much help to you I know but are you willing to share the software :sly
I've just sourced a Panasonic Toughbook purely for this use, what cables are you using?

 

[davenclaire]

Not much help to you I know but are you willing to share the software :sly
I've just sourced a Panasonic Toughbook purely for this use, what cables are you using?

iv got everything needed to plug into the terrano all it does is read live data fault codes and resetss

get looking for that mini filter

 

[jonela]

I have the Nissan consult inteface that plugs in to the multipin under the dash, a serial port ,male female and a USB<->Serial adapter In to an old Dell Latitude X300 I bought just for the job, Pity I have no idea what I'm doing!

 

[rustic]

Did the paperclip trick and it is showed two fault codes
13 Engine coolant sensor
43 Accelerator pedal position,this is why I changed the pedal
Engine coolant sensor was replaced 5000 miles ago as the needle hardly moved and I thought it was faulty after it was changed it was no different.
I have cleaned the maff with contact cleaner,but not replaced it

On my Td Mav, there are in fact 3 temperature sensors, one for the gauge, one for the glow plugs, and one for the controller.

So you may still have a faulty sensor, as you haven't changed the right one.:nenau

:thumb2

 

[davenclaire]

On my Td Mav, there are in fact 3 temperature sensors, one for the gauge, one for the glow plugs, and one for the controller.

So you may still have a faulty sensor, as you haven't changed the right one.:nenau

:thumb2

none of which will cause this problem

 

[jonela]

Has any one else used ECUTalk, its a stand alone program and gives lots of readings with good visual gauges, but unlike me you need to know how to use it!

 

[spautoparts]

none of which will cause this problem

The coolant temperature sensor measures the temperature of the coolant then sends the info to the ecu which adjusts the injection timing and quantity. If its faulty it could cause under / over fueling.