1997 p38

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penska said:
Hey guys just an update it's been seen by a machanic and been told there's a high resistance fault between crank shaft sensor and ecu advised on getting a new wiring loom not sure what could of caused this
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Think you've been unlucky there. I would have thought the connections at each end or the sensor itself would be more likely than the loom itself but I guess he knows what he is doing. Is it 1 particular wire that is broken / corroded inside? Easier just to bypass that wire and cable tie a new one to the bundle?
 
penska said:
Hey guys just an update it's been seen by a machanic and been told there's a high resistance fault between crank shaft sensor and ecu advised on getting a new wiring loom not sure what could of caused this
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Pay no attention to that i find it hard to believe. Find out why you have air in clear pipe. Check function of lift pump first job. Details of how to do this in tech archive.
 
I wouldn't swap your wiring loom unless it was badly cracked. Inside a loom wires are usually well protected. On a v8 the heat can cause issues but my guess is a v8 loom is easier to change than a diesel. Initially fix the problem.run a wire . Don't commit to finding and fitting a loom until your certain it will cure the issue. Such guesses work out very expensive and I think garages really need to think( and test) carefully before committing to this course.
Finding a loom that's in better condition than yours is the first issue then obviously fitting is your next task
 
1 find wiring diagram for your vehicle
2 disconnect ECU and crank sensor
3 find correct wire colour and plug at ECU ( obvious at sensor)
4 probe using a paper clip in the plug( or a proper probe) and at the crank sensor on ohms.
5 report back
 
It's not the in-tank pump. I 've run my car for more than 3 months with a dead in-tank pump. You need to crank 5-6 times to get it started when cold and when going above 80 , you will feel that it's not pulling as usual.
Also, I have started my car with Crank sensor disconnected but the engine scream to high RPM immediately. Anyways it will start.
My guess , your problem is either a playful stop solenoid or the immobilizer.
 
kapilamuni said:
It's not the in-tank pump. I 've run my car for more than 3 months with a dead in-tank pump. You need to crank 5-6 times to get it started when cold and when going above 80 , you will feel that it's not pulling as usual.
Also, I have started my car with Crank sensor disconnected but the engine scream to high RPM immediately. Anyways it will start.
My guess , your problem is either a playful stop solenoid or the immobilizer.
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But maybe a good idea to check if it's working first job do you not think. In red is the time when air is sucked in via duff filter O'rings.
 
wammers said:
But maybe a good idea to check if it's working first job do you not think. In red is the time when air is sucked in via duff filter O'rings.
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Tony, don't you think Kapilamuni, has a point?seeing that he had had his engine to pieces to do the timing chains ,after which it wouldn't start,we never did get to the bottom why and his fip and the alternator debacle his advice would fill anyone with confidence. When the op posted he had air in the clear line after I initially asked him then I assumed that anyone with a modicum of sence would know with diesels AIR in the fuel line is a no no.:rolleyes::D horse to water springs to mind mate.
 
YES, If the filter o-rings are bad enough to let air in then those need replacing first. In tank pump & crank sensor/wiring harness are a waste of time.
In tank pump is not required to start the engine, at all.
 
kapilamuni said:
YES, If the filter o-rings are bad enough to let air in then those need replacing first. In tank pump & crank sensor/wiring harness are a waste of time.
In tank pump is not required to start the engine, at all.
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If the tank is more than 1/4 full and your not parked with the front higher than the back. If the tank pump is surplus to requirement then when were they factory fitted.
 
Remember, the FIP is not a lift or suction pump....it is a distribution pump, it pressurises the fuel charge and distributes it to the injectors one by one.

By the laws of physics, when is pumps the charge to the injector it does create a pressure differential which ultimately will draw more fuel up the fuel lines from the tank - BUT - it is not and never was designed as a lift or suction pump - hence why at high rpms they struggle if the in tank pump is weak of failed - as it doesn't have the power to suck the required voume of fuel.

The ITP, is designed to maintain a positive pressure through the fuel filter to the FIP - and it is very much needed - even if 'technically' the engine will run IF the FIP is in good order and timed correctly - and not worn or maladjusted.
 
kapilamuni said:
YES, If the filter o-rings are bad enough to let air in then those need replacing first. In tank pump & crank sensor/wiring harness are a waste of time.
In tank pump is not required to start the engine, at all.
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Not entirely correct. If the lift pump has failed and you have a lift pump with an integral NRV, whilst the engine may start as long as your battery is good, it will not sustain and peter out. As the injection pump will not apply enough suction to pull fuel past the NRV . Air is likely to be sucked in past filter O'rings. In the case of a failed lift pump without an NRV providing there is sufficient fuel in the tank the engine will start and run but the lack of pressure from the lift pump will effect acceleration and power on hills.
 
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wammers said:
......................... Air is likely to be sucked in past filter O'rings. In the case of a failed lift pump without an NRV providing there is sufficient fuel in the tank the engine will start and run but the lack of pressure from the lift pump will effect acceleration and power on hills.......
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That's what I was telling in a different way. The ITP has no NRV, in my case.
And that 'sufficient fuel in the tank..' is not necessarily required. I have started & ran mine even when the 'low fuel' warning light 'ON'.
Also, that 'FIP timed correctly........' is not valid with my car. It's always on ' injection timing out of range' fault., for the last two years. ( Wammers knows better than me. ;)). Yet, with my recent issue with the new fuse box, new voltage regulator... & continuously running ITP, I removed the ITP relay and it started fine.

I came to know the ITP was not working only after I removed the fuel filter for replacement . That was my very first encounter with the P38 diesel & I got it started & running.

Tell me, if you were to buy a diesel engine from the breakers yard, how do you start it ?
 
kapilamuni said:
That's what I was telling in a different way. The ITP has no NRV, in my case.
And that 'sufficient fuel in the tank..' is not necessarily required. I have started & ran mine even when the 'low fuel' warning light 'ON'.
Also, that 'FIP timed correctly........' is not valid with my car. It's always on ' injection timing out of range' fault., for the last two years. ( Wammers knows better than me. ;)). Yet, with my recent issue with the new fuse box, new voltage regulator... & continuously running ITP, I removed the ITP relay and it started fine.

I came to know the ITP was not working only after I removed the fuel filter for replacement . That was my very first encounter with the P38 diesel & I got it started & running.

Tell me, if you were to buy a diesel engine from the breakers yard, how do you start it ?
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That is because if the chains are correct which you maintain they are. There is an internal injection pump problem. With the Engine locked at TDC number one firing, you should be able to get 2 mm plus lift on cam without getting near the end of the adjustment slot. If the chains are correct engine locked at TDC and you can only get 0.75 mm lift with pump fully towards engine an internal pump problem is obvious. It is unlikely that the cross drive has worn out but possible. I think you have dropped the piston thrust spacer but you are adamant you have not, or maybe disassembled the timing device and incorrectly assembled it. There is only one way to find out get the pump looked at. Please don't do it yourself. :D;)
 
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tomcat59alan said:
How did you manage to bleed the system after changing the fuel filter?
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Fill up new filter with diesel and fit it. Fit a piece of clear tubing to filter input line.(there is a joint in my car in that line)Fix the other end to a 5 ltr diesel can and hang it above the level of the filter. Loosen the filter to inj pump line at the inj pump and allow diesel to flow then close it. If your battery is good it will fire up within few turns. After running it for a while you can reconnect the filter input.

Wammers, I agree with you that something wrong with the pump. But I doubt it,s that spacer for,
1. I was extremely careful when installing the pump head o-ring. (my first such attempt, watched youtube videos on a VW Passat several times prior to this).
2. Car ran perfectly for about 2 n half years. Problem started after Dec 2016 with timing chain replacement.
3. I bought a dud inj pump, dirt cheap from bay e. Removed the head complete & the said spacer was held at the camplate(?) centre, even after turning it upside down it remained intact. I had to push it out . May be it's varnished. the spacer is about 2 mm thick with diameter about 8mm, (didn't measure properly).
4. I have read on other forums, dropping the said spacer will shorten the inj pump life to few minutes (?). as the plunger will hit the camplate like a hammer, it said.

My apologies to OP for hijacking his thread.
 
kapilamuni said:
Fill up new filter with diesel and fit it. Fit a piece of clear tubing to filter input line.(there is a joint in my car in that line)Fix the other end to a 5 ltr diesel can and hang it above the level of the filter. Loosen the filter to inj pump line at the inj pump and allow diesel to flow then close it. If your battery is good it will fire up within few turns. After running it for a while you can reconnect the filter input.

Wammers, I agree with you that something wrong with the pump. But I doubt it,s that spacer for,
1. I was extremely careful when installing the pump head o-ring. (my first such attempt, watched youtube videos on a VW Passat several times prior to this).
2. Car ran perfectly for about 2 n half years. Problem started after Dec 2016 with timing chain replacement.
3. I bought a dud inj pump, dirt cheap from bay e. Removed the head complete & the said spacer was held at the camplate(?) centre, even after turning it upside down it remained intact. I had to push it out . May be it's varnished. the spacer is about 2 mm thick with diameter about 8mm, (didn't measure properly).
4. I have read on other forums, dropping the said spacer will shorten the inj pump life to few minutes (?). as the plunger will hit the camplate like a hammer, it said.

My apologies to OP for hijacking his thread.
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I am not really bothered what you read on other forums sometimes their advise is crap. The drive shaft with the woodruff key in it is connected to the rotating cam and piston assembly by a cross connector it is VERY unlikely that has failed. Unless you have stripped it an assembled it incorrectly the only other thing it can be is the spacer displaced. I wish you would start listening. If the pump is not on full cam when you loosen the pressure head to replace the O'ring the spacer will fall out. Did you have the mid section off when you did it, if not how did you know the pump was on full cam?
 
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