1.9 cdti Hesitation at 2500 rpm

**alkez100** · 23rd April 2010, 11:46

Hi All,

My Signum has recently developed an Hesitation/Missfire around 2500 rpm any gear.
It used to do it bang on 2500 rpm which i put down to a mapping problem, but now its anywhere between 2100 and 2800 rpm random.
This only hapens when the Engine is warm if this helps.
No warning lights are present and the car drives very well apart from that.
Egr has been cleaned.
New air filters etc. changed.
New Glow plugs fitted.
Regards Alan.

**Dan_BlackSRi** · 23rd April 2010, 11:47

Which CDTi do you have..?

Could be the 3rd injector issue.
EGR issues can cause this too, was it fully stripped when cleaned, solenoid etc..?

**alkez100** · 23rd April 2010, 11:55

I cleaned the EGR myself until no gunk came out and the solenoid was moving freely.

It looks to have a modified 3rd injector fitted as its of a different colour to the rest.
But i would say the soldering looks a bit dodgy.
Alan.

**the-wizard** · 24th April 2010, 23:53

Have you had a remap? or a fitted plug & play box!, take the box off or go back to remap co, if not the soldering needs checking for deffo on the 3rd injector plug!, Any fault codes coming on ?, clean the boost sensor + throttle body! also, Both these jobs are covered in the 'how 2's' section. It may also be worth pulling off the other injector plugs 2 check for corroision or a dirty connection.

**alkez100** · 26th April 2010, 11:47

I had a new Throttle Body fitted 7 Months ago but i will give it a go.

The car has done 145,000 miles, do you think i should replace all the injector plugs as they are so cheap to buy?

It has never had a box fitted since i have owned it and its been running fine until the last 2 months.
no fault codes. it's so fraustrating as it just in the rev range for normal cruise speed you can hear the engine/airbox making a gulping sound.
May be i just need it remapping.
Regards Alan

**dave r** · 26th April 2010, 21:03

Originally Posted by the-wizard

Have you had a remap? or a fitted plug & play box!, take the box off or go back to remap co, if not the soldering needs checking for deffo on the 3rd injector plug!, Any fault codes coming on ?, clean the boost sensor + throttle body! also, Both these jobs are covered in the 'how 2's' section. It may also be worth pulling off the other injector plugs 2 check for corroision or a dirty connection.

sorry to jump in here, wizard did you say there's a how2 clean throttle body cdti 1.9 150, cant find it matey cheers dave..

**GazVXLINE170** · 26th April 2010, 21:17

Originally Posted by dave r

sorry to jump in here, wizard did you say there's a how2 clean throttle body cdti 1.9 150, cant find it matey cheers dave..

Check Vaux Man G or for:

1.9 150 CDTI Throttle Body Location

and

Throttle Body

The later thread is really for the electronics that control it...

Gazza4

**alkez100** · 3rd May 2010, 21:18

Thanks for all your help, over the weekend i have cleaned the opening of the Throttle body and cleaned again the EGR valve both of which were quite clean as they were new last August. I have also fitted a new Boost sensor which to be honest look knackered. Anyway two days and no sign of the problem. i would say for £25 the boost sensor is a good option to try.