PhilM Star said:

On the thread "1.9 JTD - Replace crankshaft sensor - now won't start at all."

John55 said;
"Doesn't the JTD have 2 sensors, one on the flywheel and one on the cam shaft?"

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I believe that's true.

Crankshaft rotates at some speed as flywheel.
Camshaft is different being belt driven and would need a different sensor.

So if i'm understanding this flywheel sensor & crankshaft sensor (crank sensor) are synonymous and camshaft sensor is a different thing alltogether?

The Cam shaft is driven at exactly half the speed of the crank shaft, through a ribbed belt, so in theory only one sensor is needed as the position of the cam shaft can always be calculated.
Why there are 2 sensors is because they provide different information and when combined can tell the ECU exactly where the engine is.
The crank shaft sensor provides a pulse every rotation of the crank shaft, usually at TDC.
The cam shaft sensor provides a continuous stream of pulses , one for every small angle of rotation of the engine. The cam shaft sensor only gives relative information, where as the crank shaft sensor gives absolute information as to the position of the engine.
The ECU then knows exactly where the engine is by detecting the crank sensor pulse and then counting the cam sensor pulses after it.

Its a little while since I updated this thread so I thought I would post recent events. After coping with Snow, Ice and Flu over Decenber and getting through Christmas and New Year I finally got round to getting under the car and having a look at this hanging sensor. Looking up the back of the engine slightly to the left of centre near the top I couldnt see any holes where the hanging sensor might have come from. After a bit of puzzling and looking around I realised that the top of a sensor I could see in the position I was adivsed to look was in fact a crank sensor. What had happened was that Nationwide in Stoke had tried installing a new sensor to see if that was the problem but had just left the old one hanging and not taken out the one they used to test with. Totaly thrown off track by this. The car still wouldnt start so I bit the bullit and had it towed to a garage by my recovery service. Strange thing was when they arrived they tried to start it and it ran for about 30 seconds before cutting out again and refusing to start. This seems to prove it is starved of air or fuel. Its been in the garage a few weeks now but I hope to have it back next week.

Check the immobiliser. Stilos are prone to the imobiliser aerial around the key barrel failing and the ECU wont start the car if it cant detect the key.

I have finally got the car back this week The latest analysis after connecting to diag kit is that the fuel pump is at fault. No errors are being read from the ecu.
The car starts and I have driven around in it but get the power loss problem occasionally from a start or moving off from a junction etc. Can be quite scary. I have left the car idling for the last hour and it justs purrs along. I cant see how this can be a faulty fuel pump. I asked for the ecu to be checked in case the signal to feed fuel wasnt always being delivered and nothing was found. Ive also been told an in flight recorder was used but nothing came up.

Would like to try a new fuel pump but I am told that it will cost £2000 to fit a new one and that they are coded to the ecu (hence the price) Is this correct? Can the pump in situ be removed and tested?

Have you tried disconnecting the air mass meter (probably not the right name) It's the sensor that measures the temp and humidity of the air. Disconnect and drive around. If it runs better, replace and reconnect.

gr J

I tested the MAF sensor at the start of this episode. It was a little dirty but not too bad. Cleaned it up with electrical contact cleaner. There was no real difference after I cleaned it. Thanks for the advice.

Ive driven around quite a bit in it today and it runs fine sometimes but just occasionally looses power. This can be when starting off and picks up when the accelerator is pushed to the floor. although its a bit jerky and not a smooth build up to full power. At other times you can just feel a slight judder, almost like a cylinder not firing and then it goes back to normal. I'm thinking of putting additional earth connections on the car and inspecting all the tubing in the engine. I dont think this is the turbo as that only kicks in at higher revs. I'm baffled unless it is the fuel pump

Nothing wrong with checking for bad earths of other bad connections but never heard of a faulty JTD fuel pump although I suppose there's always the 1st time for everything :chin:

Presume you've checked the EGR by blocking it as that's one of the most commons problems that matches your symptoms somewhat.

Point about the MAF sensor is that the engine should run a lot better if it's left disconnected (should it be suspect)

Argonought said:

Point about the MAF sensor is that the engine should run a lot better if it's left disconnected (should it be suspect)

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That's exactly what I meant.
Although I read in another thread that you've tried to kill the pump by filling up with gas I would think that wouldn't cause intermittant problems.

gr J

I did try disconnecting the MAF before I cleaned it. There was no difference in performance so I just gave it a clean. I did find that it had been secured with plastic ties instead of jubille clips or "Fiat Clips". I have remidied that.

Havnt tried blocking the EGR. I think I recall reading a post where a custom part was made from a piece of tin. I'll look it up.

However, tonight I drove about a mile in it and parked up, stayed for a couple of hours and the thing wouldnt start:bang:, not even when I tried to jump it from another car. All the usual lights and errors are now showing (EDB, airbag, alternator etc). It does behave as if no fuel is getting through (checked the fuel cut of button). The weather is cold and damp which was the case the last time this happened. Could some sort of condensation be building up somewhere? Ive read posts about the ecu getting damp and connections shorting.

A3jeroen said:

I read in another thread that you've tried to kill the pump by filling up with gas

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I did join the band of fools who misfueled but ran the car for many miles since then. The garage thought that some wear might have occured in the pump due to the lower viscosity of gas over diesel making some things scrape together. I'm on the verge of giving in and seeing what Fiat will charge to sort it out then decide which child I will need to sell to fund it

PhilM Star said:

Havnt tried blocking the EGR. I think I recall reading a post where a custom part was made from a piece of tin. I'll look it up.

However, tonight I drove about a mile in it and parked up, stayed for a couple of hours and the thing wouldnt start:bang:, not even when I tried to jump it from another car. All the usual lights and errors are now showing (EDB, airbag, alternator etc). It does behave as if no fuel is getting through (checked the fuel cut of button). The weather is cold and damp which was the case the last time this happened. Could some sort of condensation be building up somewhere? Ive read posts about the ecu getting damp and connections shorting.

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The EGR wont stop the engine starting so you can discount that.

Assuming you got all the warnings BEFORE you tried a jump start then certainly sounds like a bad earth or bad connection somewhere.

Might be worth stripping out the ECU and looking for corrosion on contacts etc plus have a play with the favourite D4 connector up behind the battery.

Thanks, I'll dig out the engineers service CD and look up the procedure for taking out the ecu and have a look at the D4. I still have some electrical contact cleaner so may as well use it. I think the battery is pretty flat now so will have to put it on charge.

I went to the local FIAT dealer to ask what their opinion was on the non starting and loss of power. I have recently been made redundant and dont have much mmoney to spend on a car (at least i'm not driving 130 miles a day anymore) I mentioned there was a local fuel injection specialist in the area which all the taxi drivers use. They agreed it would be worth trying these before paying FIAT prices. Took it in and after a few days got a call saying the EGR was sticking and despite having given it a very good clean it still wasnt right, Said they could fit a new one for £130. I agreed and the car now starts every time and has excellent fuel economy and performance. I looks like Argo was right a few posts ago re loss of power although he also commented EGR shouldnt cause a no start. I'm still getting EDB and ABS warnings after many good starts and have just started getting the glowplug warning again. Read somewhere that once one goes others soon follow so will check again. Just started getting the stop light error so maybe I have the brake switch problem, noted elsewhere, as well. All in all it looks like the problems are minor now and the car can be relied on. Thanks to all who have helped in any way with all this, its been a long haul:shakehead:

Sorry I misled you on the EGR (post # 53). I know they can cause stalling but yours is the first I've heard of which stop the engine starting at all.

That really is the point of blocking it (post #49) as it always proves it one way or the other - and it's not that big a job.

Anyway, glad you're back on the road again