Guide for Direct Ignition cassette and spark plug service - all DI-equipped vehicles

Using non-resistor spark plugs could cause several different types of fault symptoms and driveability problems in the car. The DI uses the spark plugs are used to monitor the combustion process.
An incorrect spark plug gap (excessive wear) can also lead to driveability problems. Use of non-resistor spark plugs could also destroy the DI cassette.

! - Spark plug burn-off - !

Automatic spark plug burn-off is carried out with a burst of sparks each time the engine is switched off. Burn-off is carried out in all cylinders simultaneously and lasts for 5 seconds at a rate of 210 sparks per second.
! -This Is Lethal Current Use Extreme Caution- !

Therefore, it is very important to adhere to the following guidelines :

When replacing the spark plugs it's important to check following:

Before installation of the DI cassette:


Recommended spark plugs for DI-equipped cars: 1990->

NGKBCPR7ES 91 12 541

900 B204 TURBO (94-98)
9000 B202 TURBO with DI
9000 B234 TURBO
9-3 B204 TURBO 185 HP (1999)

B207L / B207R .9-1.0mm 9-3 SS
B205R 9-3/9-5
B235R 9-3/9-5

NGK BCR8ES   Very High output cars. Gap 1.0-.9mm
NGKBCPR6ES - 11 91 17 565 9000 B234 Nat. Asp. with DI
9-5 B235 TURBO
NGKBKR7ES -11 91 71 307 9-5 B308 V6
NGKPFR7H - 10 91 88 681

Discontinued > Use NGKPFR6H - 10
Hard Use only. Prone to cold fouling on short trips.
(HOT T7 cars)
9-3 B205 TURBO 185 HP (2000>)
9-3 B205 TURBO 205 HP
9-3 B235 TURBO 230 HP VIGGEN

NGKPFR6T-10G   B207E / B207L .9-1.0mm 9-3 SS
NGKPFR6H - 10 93 99 866

9-3 B204 TURBO 200 HP (1999)
9-3 B205 TURBO 185 HP (2000>)
9-3 B205 TURBO 205 HP
9-3 B235 TURBO 230 HP VIGGEN


"7" series spark plugs have a colder heat range than "6" series and are, therefore, commonly used as an alternative plug on cars consistently run at high speeds or under heavy loads. Running too cold of plug for short trips will lead to fouling. This is more of a problem in the winter.

"R" in the NGK plug designation signifies resistor type this is very important.

"P" in the NGK plug designation signifies Platinum electrodes. These are more expensive but last a bit longer. It is ok to run copper "C" plugs in the application that originaly had platinums as a cost savings but they will requre more frequent sevice.

If you have any questions please contact via email: parts at
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