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Opravené vozidlo

IHR Technika s.r.o.

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Renault Scenic - tough job for 4 expert workshops

08.04.2011 | aktualizováno 02.09.2011 13:51:15 0 8469x

Informace o vozidle

VIN:
Výrobce:	Renault
Model:	Scenic II
Rok výroby:	2004
Kód motoru:	1.6 16V
Typ motoru:	K4M-782
Výkon (kW):	83 kW
Převodovka:	Manuální
Palivo:	Benzín
Najeto:	0 km

paměť závad nečtena
nelze se spojit / asi chyba auta

Doposud provedeno bez úspěchu

1 x throttle flap
3 x ECU
1 x cable bundle - all cables disconnected and replaced with distribution frames from other car.
1 x Engine head and cam shaft dismounted and made a good inspection.
All with no succes, fault occures again after cca 60Kms repeatedly.

Závěr

VOZIDLO JSEM NEOPRAVOVAL

Repaired: First inspection with the installation of incorrect spark plugs started the problem in the first place. The following repair attempts focused to much on diagnostics and guess work instead of performing proper measurements.

Obrázky, fotografie a soubory

Pic.1: Scene of the crime. (4240/1)

Wiew on engine was spectacular. All adjusted cables with distribution frames leading to ECU are originaly from another car. All pipes are done finely. The determination to solve the fault even for that price was more than admirable.

Pic. 2: Detail of cable bundles in engine space (4240/3)

This has to cost a lot of time and effort..

Pic. 3: FCD - our first diagnstical step (4240/4)

We want to be fast in end, so we chose easiest connection of ignition. On that engine it is connection on primary circuit. For the first tests it is enought.

Pic. 4: FCD - The result of thr test of primary circuit. (4240/5)

Chnnels 1-4 = cylinders 1 to 4...
Cylinders 1 and 4 are burning nearly exemplaryly. Burning time on cylinders 2 and 3 is shorter. In secondary circuit of 2 and 3 cylinder has to be fault... ( the pikes are not visible thanks to long time of recording and 4 recorded channels )

Pic. 5: FCD Oscilograph numb.2 (4240/6)

red = cylinders 2 and 3 (fault in spark gap is clearly visible)
blue = cylinders 1 and 4 ( here is sometime visible nonusual high voltage and short burning time )
On blue signal with highest ignition voltage is visible the jump of short spark, which jumps probably somewhere between electrodes of spark plug.
This phenomenon is probably recognized by ECU as misfires. Circuit for plugs 1 and 4 is controled together.

Pic. 6: FCD Oscilograph numb.3 (4240/7)

black = cylinders 2 and 3
blue = cylinders 1 and 4

Pic. 7: Defect numb. 1 - found in 15 minutes (4240/8)

This coil has endless resistance ( cylinder 2 ) That jump voltage causes higher electromagneticall disturbance, which matter to ECU, and this then records unknown faults.

Pic.8: Defect numb. 1 - (4240/9)

Ignition coil of second cylinder has endless resistance on secondary curl.

Pic. 9: Defect numb. 2 - founded after 5 minutes (4240/10)

Those spark plugs are not recommended by manofacturer of car neither of plugs. Due to brisk there should be plags with DR15YC mark, the "R" is mising there: R = with antijamming resistance.

Pic. 10: Sample signals for Renault Sagem system (4240/11)

Ch A1: source 12 Volt for ignition couils 1 and 4 readed on cylinder 1
Ch A2: Outputs from inductor number . 1. to inductor number 4. (serial setting )
Ch A3: Outputs from inductor number 2. to inductor number 3. (serial setting )
Ch A4: source 12 Volt for ignition couils 2 and 3 readed on cylinder 2
Ch A5: Outputs from inductor number . 3. to inductor number 4. (serial setting )
Ch A6: Common switching to frame for 2 and 3 cylinder readed on cylinder 3
Ch B1: Common switching to frame for 1 and 4 cylinder readed on cylinder 4
Ch B2: Outputs from inductor number 4 to inductor number 1 (serial setting )
Sample signals for Renault Sagem system