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(Post Link) post #1 of 6 Old 04-11-12 Thread Starter
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Help gt jtdm problems starting / strange noises

Hi all

after 6 months trouble free motoring Houston we have a problem!!!

about 5 weeks ago i gave her a full service all filters oil ect, and a dash of injector cleaner (i even became a contortionist for 30 min to replace the pollen filters)

The next day we set off on a 400 mile trip all going well until 350 miles in we got stuck in traffic,i got a bit lazy and went to pull away in a high gear- total loss of power and a awful knocking from the engine the sound is what i can only describe as a belt slapping against a casing rising in frequency as the revs tried to rise, 20 seconds later all good going well again pulled over and had a quick look, belts all ok, so we carried on, only now a lack of power until the turbo kicks in -
egr i thought but having no tools whilst away had to wait until we got home,

checked egr and it is a fairly new unit and it has the modified gasket on,

the past week she has been getting difficult to start both hot and cold, then this weekend nearly impossible,rough idle and a bit of smoke, also got a noise like compressor stall or what would be waste gate chatter from air intake on lift off, and that total loss of power and awful noise has happened again twice

so today had a couple of hours digging -
no trouble codes at all
egr cleaned and checked on diagnostics opening and closing fine
maf cleaned and is measuring spot on with desired on diagnostics
map sensor cleaned
all hoses checked inc small vacum
all parameters checked inc fuel pressures ect are within desired, boost pressure slightly high maybe but nothing mad

EXCEPT injector correction-
at normal temp

at tickover -

inj 1 -3.08
inj 2 +5.08
inj 3 -4.36
inj 4 +1.42

at 2000rmp

inj 1 +0.05
inj 2 -1.15
inj 3 -0.37
inj 4 +1.25

i believe Bosch recommend + or - 0.9 so these are way out
is it possible for them all to be so far out maybe injector cleaner knackered them up?
or am i missing something obvious ??? maybe compression down, hope not on 50000 miles

once started and you get going it drives fine when on turbo just a low on power before

she is using no oil or water and temp is fine

so looks like injectors out for a clean or rebuild and compression test bit worried about the noises though?

sorry for the long winded post but any advice will be most appreciated

this is my wifes daily comuter so i am starting to get it in the neck for not fixing her


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Hi, the noises, loss of power, smoke and difficulty starting all point towards the timing jumping a tooth but you would expect that to throw up a cam sensor fault.
The injector values could be leaking injector seals or even injectors leaking from the body, is there any fuel or build up around the injectors.?
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(Post Link) post #3 of 6 Old 04-11-12 Thread Starter
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hi, thanks for the quick reply, when it lost all power and made the noise first time i was thinking exactly along the same lines but then it was ok for 3 weeks being used everyday for a 50 mile round trip,then when its done it since its only lasted 20 sec or so again,
the starting problem has been getting gradually worst this week only, my good lady has just got back from work, and tonight from cold it started not to bad but tick over was really lumpy yet when she left this afternoon it only just started after many attempts ??
there is no evidence of fuel or build up around the injectors and no sounds around them so i believe the seals are sound
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Hello Dc,

You seem to have covered everything, except possibly the clutch in the pulley of the alternator; I do seem to recall another post which identified this ( eventually!) which gave a slapping noise; might also account for poor starting, our diesels take a lot of CCA ( cold cranking amps) out of the battery on starting. Is your battery/ earth straps in good nick? Just a thought.

Hope it helps
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just a thought here but I had realy bad starting lumpy idle last winter and it turned out to be the plugs that go into the injectors were corroding so folded up a fine bit of emery cloth to poke in the holes and cleaned up the pins then spray some silicone spray in there..... sorted
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(Post Link) post #6 of 6 Old 05-12-12 Thread Starter
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update swirl flaps destruction!!!!

Hi all,

just to update we got to the bottom of the above problems,

due to me working away i took her in to graham eddy motori in penzance,
soon found low compression and after stripping the head off it became evident swirl flaps 2 and 4 had gone through

head is being reconditioned now 6 new valves needed,

i picked up the manifold from graham to have a look and on inspection the flaps on these newer type manifolds are operated by a internal plastic rack and pinion set up, 2 and 4 were completely worn away on the rack so these flaps must have been forced shut by induction until they just gave up,
why change the flaps from plastic to metal and then the mechanism from metal to plastic???
i think a few more of these types of incidents are on the cards,

so i have converted the manifold and removed all the remaining flaps completely but left the mechanisms in so the car will believe they are still there,

just got to wait for the head to be finished then graham has the unenviable task of piecing it all back together

also a big shout out to graham eddy really nice bloke and well recommended

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jtdm , noises , problems , starting , strange

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