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[Fleagle]

Hi all - new to this forum. Hope you can please help.

I had my 2001 3.1TD for 3 years now despite the usual jokes about Massey Fergusson tractors having more sophisticated engines, I do actually quite like my Jeep.  

Anyway, a couple of problems  you may help me with to save pennies from a main stealer.

Firstly, a few days ago I was in the lake district and it was raining HARD. Streams were forming over all the narrow lanes and often some pretty big puddles. Now these have never been a problem in the past - the car has just sailed through them as if not there. However, not this one puddle which must have been a bit much. As I come out of it the other side, the engine started to misfire very badly. It would struggle to idle often cutting out (but oddly would start up again no problem). Being in the middle of nowhere I had to carry on and after about half a mile the missfiring got less and less and it would now idle fine.

My theory at that time was that something got wet...it didnt like it...and when it dried off it was happy again. However, something was seriously wrong with the power. Although the engine is now smooth again, it has no top end power whatsoever say above 1700rpm when on the gas to climb hills or overtake something on a motorway. Mpg is also well down - to about 20mpg - I usually get about 28/29 on a motorway.

I've checked all the obvious stuff like hoses blown off and all connectors all sound. There's no black smoke. No engine warning light. Using the ignition key method to examine ECU codes - none are reported.

I want to get to the bottom of this myself but need pointing in the right direction if anyone has had simililar problems with water trouble on this engine.

My worse fear was that water had got sucked in causing vapour block on the turbo impellor fins or pistons  but that seems unlikely - it was hardly a river and the intake is pretty much guarded high up.

Any ideas appreciated. eg How can I test wastegate operation for example ? maybe it stuck open. What about the fuel pre heat ? Is there an easy point I can measure turbo boost pressure ?
Thanks
Neil.

[dxmedia]

You should be able to measure boost pressure on any pipe which comes off the inlet tract post the turbo, there's more than likely a couple of rubber pipes coming off for on boost fuelling - make sure that these have't come adrift (should go into the fuel pump).

I've never seen under the bonnet of a 3.1 jeep though

[scrw]

What state is your air filter in? Any signs of water on it?

[Mike Pavelin]

Either the Bosch diesel controller has gone into limp mode due to water in the electrics, you have bent a conrod or five, or both.

You can't get codes off the Bosch controller using the key method, you need a dealer's DRBIII scan tool or another advanced scanner. A cheapo scan tool will not do. It is possible the engine may have ingested water, the air intake is below the headlamp and it does happen. A compression check would confirm.

[Fleagle]

Thanks for the thoughts.

- The air filter is fine - no damage nor signs of water ingress.

 - conrods....mmmm ..there's a sobering thought. I would assume if it was them I would be getting one hell of a noise from the engine and it would be far from smooth as it still at all speeds (just no power top end)

- Bosch Injector controller - can it be taken out of limp home mode ?i.e.  short pins out / disconnect from battery for 12 hours or whatever ?

Cheers
Neil.

[Mike Pavelin]

Disconnect the battery for a minute, it might work, otherwise you'll have to go to a dealer or Bosch diesel specialist and get it scanned.

[Fleagle]

Disconnect the battery for a minute, it might work, otherwise you'll have to go to a dealer or Bosch diesel specialist and get it scanned.

Yeah tried that Mike, - in fact left it disconnected for a day... No difference when I reconnected.

I have no idea how sophisticated the reporting codes are from this bosch system, I know some other cars that can tell you the colour of your under pants and what you had for lunch and yet others can bearly tell you if the pistons have dropped out of the bottom of the sump.

[Bubba]

i realy hope i am wrong but bent rod or rods hits the spot for me

[Fleagle]

i realy hope i am wrong but bent rod or rods hits the spot for me

 :shock:  :shock:  :shock:  :shock:

mmmmmm.  gulp.  this is where I'm hoping someone can tell me a sure fire way of telling if it is the rods without having to strip the block down. :oops:

Famous last words I know but.....the puddle wasnt that deep though just a couple of inches, it's not as if the intake was submerged and it sucked up pure water. At most it would have been remanants of the "splash" that got vapourised - for signifcant water ingress I would have expected the air filter to be shredded - but hey I'm no expert.

cheers
Neil

[PtP]

I recently had a load of rain water get into the air-box on my petrol TJ via the snorkel. This caused the paper filter to become sodden wet and the engine just wouldn’t rev.

I removed the filter and dried it out whilst waiting for the new K&N one, but just looking at the old paper filter is was quite obvious that it had been wet. So if there is no significant water damage to yours, then how else could water have got in to the cylinders to cause the con-rods to bend?

Surely, you’ll not get sufficient water to pass through a paper filter unless you drown the intake which hasn’t happened in this instance?

Also water from a puddle is generally muddy and it’s quite obvious to see the stain in the bottom of the air-box as well as on the filter.

Just my 2p worth!

[Fleagle]

Well, lets hope its not major mechanicals at this stage. I'm still hoping its just a sensor or something thats gone  wrong and causing the ecu to be on the cautious side.

As mike says, I think i need to find specialist to read the codes if any.

Does this forum allow folk to make recomendations for garages ? - I know some car forums can be a bit funny with such stuff....scared of litigation if something bad happens etc. If so, any help would be much appreciated to find a jeep specialist in the north cheshire area.

Thanks
Neil

[Bubba]

we dont normaly have a problem with recomendations  good and bad but if its not good a simple i would not use them again saves any problems

[Mike Pavelin]

A compression test will confirm if there are bent rods.

[JamesH]

Find a local Bosch Diesel Specialist. They can scan your system and might be easier to get to and cheaper than a dealership.

[Fleagle]

I'd just likt to say a big thankyou for all the friendly advice.

I've just blown the dust off my own compression tester (blimey it's been years since I needed that!) so first off I'll check compressions and if they're ok then I'll get it to a bosch specialist to check any codes and if they don't show anything then I'll pull the turobo off to have a look at the blades.

So - Does any one by chance know what "normal" compression the cylinders should be? If anyone has the workshop manual it would be great if you could look it up for me - thanks.

Neil.

[Fleagle]

well - wouldnt ya know it !

I 've managed to look at the workshop manual and while it gives the compression values for the 4.0 and 4.7 petrols it only mentions for the 3.1td what the compression ratio should be (21:1) and doesnt actually say whay the p.s.i.  should be.

Trawled the web as well but no joy. Any ideas would be gratefully received.

Thanks
Neil.

[Mike Pavelin]

Just make sure they're all about the same.

[dxmedia]

If it's a petrol compression tester it might not be up to the job for a diesel - keep an eye on it.

As above, they should all be pretty close if you don't have the actual figures.

[Fleagle]

my compression meter goes up to 300 psi - should be enough though the margin of error at that value is probably quite high.

There's gonna be a delay though on doing the compression tests, apart trying to source a special tool to remove each injector in order to connect the compression tester, each injector has rubber fuel pipes connecting each in series (fuel return I assume). Each one is VERY brittle presumeably with heat over the years. It doesnt take much pulling/prizing them off for them to crumble in your hands....as I found out at weekend.

I was hoping to get away with not needing the special tool by using a deep socket....if anyone has experience or knows for sure then please shout.

cheers
Neil.
(PS... I noticed the other day that under wide open throttle my Grand  Cherokee no longers throws black smoke out of the exhaust (was never huge amounts but always there....now its gone)......mmmmm

[scrw]

sounds like lack of fuel then

[Mike Pavelin]

You can use the glow plug holes to test the compression instead. BTW, look at the connector for the needle sensor on no.1 injector, this is a favourite for water ingress and will put the Bosch controller into limp mode.

[Fleagle]

You can use the glow plug holes to test the compression instead. BTW, look at the connector for the needle sensor on no.1 injector, this is a favourite for water ingress and will put the Bosch controller into limp mode.

What does this needle sensor do ? if it was putting the ecu to limp mode I would have thought I would get the engine warning light on ?


Cheers
Neil.