General Hesitation at low revs

[uksdsgl]

My Eleganza 150 manual 1.9 JTD diesel 16V hesitates at low revs (between about 1500 and 2000 RPM) under acceleration in 2nd or 3rd gear when the engine is warm (there is no problem when the engine is cold).

The engine performs well apart from this.

The EGR valve was recently replaced.

All of your ideas as to why this is happening will be appreciated.

 

[arti_abarth]

swirl bar fallen off??

use search for above, also go to vectra c forum and search for this

 

[notorious]

I would check and clean the boost sensor.

 

[Mike Huggins]

I read this article with some interest. My Fiat Sedici has recently developed a hesitation, and the garage have no idea, because they only look at the computer read-out, (what ever happened to skilled mechanics?). Did cleaning the boost sensor cure a similar problem, or was it an educated guess. Some years ago, I had a RS Escort and that had a hesistaion connected with the Turbo, but that was much more agressive that the Sedici problem, the garage think not!!.

 

[Radlet6]

Hi

I would check to make sure the turbo pipe is ok (no splits etc). I would not suspect the boost sensor; I recently cleaned mine as it looked like it had been on 60 Woodbines a day for the last 5 years, however this did not have any effect on bottom end performance. That said it is a 10 minute job and it wouldn't do any harm.

If the EGR is working ok, because of the hot/cold running issue, my gut reaction here is the air mass sensor (it may just need cleaning of course) - however I am prepared to be corrected on this.

What ever happened to the days when the only thing that could fail on a diesel was the fuel pump or an injector (and maybe a turbo or two)?

F*****g EU and its bl**dy emission regs. How much longer before we are all consigned to puny, strangulated 900cc hybrids designed by NASSA which cost a king's ransom (except the politicians of course - they will still need their chauffeur driven mercs/beemers/jags to take them a mile up the road)?

Only four decades, and car ownership is slowly being taken from the masses and given back to the wealthy and privileged - after all getting the proles of the road is cheaper than building new ones.

BTW I will do it before someone else does :Offtopic:

 

[cjlar]

You could try disconnecting the mass airflow meter and see if it runs smoothly. I did that with mine it was perfect, pulled like a train. A funny light came on so I reconnected it. The light stayed on for about 3 driving cycles and had no hesitation until the light went out

 

[chumbamoo]

Hello,

Could try replacing your fuel filter....

Purchased a second hand, 55,000 mile, 56 plate Sedici with the 1.9 Multijet engine that suffered hesitating at just below 1900 rpm and poor pickup from a stand still.... took this as turbo lag after reading similar threads and suggestions about the EGR being the problem. (checked mine and noted a brand new one fitted). Previous owner obviously had the same problem then gave up and part exchanged the car.

A week after buying the car it broke down! It started and idled rough but then shut down by engine management safe mode. Garage recovered and traced fault to an injector. Thank god for the warranty! Injector was replaced and car performed like new. Couldnt understand why an injector should fail after 55,000 miles!!! Few miles later the hesitating slowly returned!
Decided to change fuel filter by myself.... Bingo... old filter cartridge was made from a fabric material. Have replaced with a 'Fram' paper aftermarket type for £10. Think it had been shedding strands of fibres and sending them to the injectors and clogging them! (have binned the old filter but think it was made by 'Blue' filters... when i ran my fingernail over the surface, fibres would loosen and detach!)
Cars service history shows filter was replaced previously at approx 30,000 miles by garage!!!
Could also be fuel starvation due to the filter being clogged??
Hesitating is cured. Car has stopped kangarooing and pulls away without the need for high revs. Hope this helps to all.
Please post reply to possibly help other Sedici, SX4 and Multijet users.

 

[arti_abarth]

Fiat oem filter is made from fabric, i recently changed mine at a cost of £35 for the part

thinking about it now, my car seems to pull much better since so @Chumbamoo might be right with his suggestion