Technical jtd 150 low power in 6th under 2000rpm?

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Technical jtd 150 low power in 6th under 2000rpm?

horv2500

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hi got an issue with a 2005 croma 16v jtd, had it about 8 weeks but been between garages for about 6, drove car from london (200 miles) thought it was a bit slow esp in 6th on motorway at 60 mph having to change down to 5th.
had it booked in for loads of stuff, on the way there(next day) lost power quite bad, so had servicing done, cam belts, coil springs gear oil, filters. picked car up still slow, garage said turbo sticking, had it checked and cleaner all good (only 50k miles) still slow, no faults on ecu, he said egr ok everything good but slow.
went to another garage for him to have it ten days to say it could be? but no faults, took it to a fiat and alfa specialist, after checking egr, replaced that, he then checked dpf and sensors all good, valve/cam timing checked, inlet checked (but had new one at 33k) all good, all hoses checked + finally after noticing the car was better in the morning came to think maf, changed that (bosch) car then a lot better but didnt show any faults at any stage and reported everything was fine so the fault untraceable. the croma is now drivable, slow to set off (needing plenty of gas) then at 2000 rpm flies, goes well after that.
when you rev it, it feels slow to rev, specialist says as the car has canbus the car needs to be rolling before it allows to rev properly? im unsure, its like setting off in a cavalier 1.6d until it gets to 2k, but the car is very drivable, issue is on the motorway if its in 6th and you drop below 2k revs which is quite a lot at 2k revs is 79 mph you have to go in 5th.
i got a dtuk tuning box slapped that on to liven up the throttle, but it super flies after 2k now(those best boxes ive used) but still slow revving and not much pick up in 6th.
the car will pick up slowly eg hit a roundabout in third and it will pull slowly just takes a few seconds to get up to 2k then its off, but where you notice it the most is the motorways in 6th.
i like the car but is this how they drive? what could be the issue nearly everything has been changed?
why does it start up normally no faults just sluggish under 2k but you notice it in 6th most, i can live with it just annoying as dont use 6th its fine.
help would be appreciated
 
hi got an issue with a 2005 croma 16v jtd, had it about 8 weeks but been between garages for about 6, drove car from london (200 miles) thought it was a bit slow esp in 6th on motorway at 60 mph having to change down to 5th.
had it booked in for loads of stuff, on the way there(next day) lost power quite bad, so had servicing done, cam belts, coil springs gear oil, filters. picked car up still slow, garage said turbo sticking, had it checked and cleaner all good (only 50k miles) still slow, no faults on ecu, he said egr ok everything good but slow.
went to another garage for him to have it ten days to say it could be? but no faults, took it to a fiat and alfa specialist, after checking egr, replaced that, he then checked dpf and sensors all good, valve/cam timing checked, inlet checked (but had new one at 33k) all good, all hoses checked + finally after noticing the car was better in the morning came to think maf, changed that (bosch) car then a lot better but didnt show any faults at any stage and reported everything was fine so the fault untraceable. the croma is now drivable, slow to set off (needing plenty of gas) then at 2000 rpm flies, goes well after that.
when you rev it, it feels slow to rev, specialist says as the car has canbus the car needs to be rolling before it allows to rev properly? im unsure, its like setting off in a cavalier 1.6d until it gets to 2k, but the car is very drivable, issue is on the motorway if its in 6th and you drop below 2k revs which is quite a lot at 2k revs is 79 mph you have to go in 5th.
i got a dtuk tuning box slapped that on to liven up the throttle, but it super flies after 2k now(those best boxes ive used) but still slow revving and not much pick up in 6th.
the car will pick up slowly eg hit a roundabout in third and it will pull slowly just takes a few seconds to get up to 2k then its off, but where you notice it the most is the motorways in 6th.
i like the car but is this how they drive? what could be the issue nearly everything has been changed?
why does it start up normally no faults just sluggish under 2k but you notice it in 6th most, i can live with it just annoying as dont use 6th its fine.
help would be appreciated

Welcome Horv-- you have done /tried quite a lot in a short time and a lot of the "usual" probs seem to have been addressed. One that isnt mentioned is the boost sensor cleaning. This is located at the side of the EGR. I cleaned mine when I changed the EGR and it is a10min job at most , when it came out it was like a blob of carbon/soot . CAREFUL cleaning with a spray of WD40 and a toothbrush revealed black plastic cage with a yellow sensor inside it. The reaction from the engine was startling and was as good as its ever gone,much better at lower revs etc.
The sluggishness in 6th gear is a little nebulous to me as mine can be the same on the motorway but cruises all day @ 70mph at about 2000/2100 revs but if it drops below these revs I have to drop it down a cog. Does your car have cruise control? when i use mine set at 70 it does not let the revs drop so manages to keep it sweet. The power band from the turbo comes in between 2000/ 3000 revs and as you say it flies above 2000 revs so there is no worry with the turbo .
Hope this helps -- our aim on here is to keep Cromas out of main dealers repair sections as much as possible(y)
 
Hi a couple of things worth a look first check the rubber pipe to the cylinder on the turbo that works the variable geometry, it can split upsetting things a good squirt of wd 40 on top of the swirl valves can free them off.
 
I'd go with cleaning the boost sensor on the basis that the odds of getting a faulty egr fitted are low. However I remember someone else having a dodgy replacement egr fitted so it's not impossible.

If the boost sensor clean doesn't help I'd try briefly fully blanking the egr (loads of posts elsewhere on this) just in case there's a problem with it or some of the pipework around it.

Also check the vac pipe from the radiator in case it's a bit loose or cracked.
 
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