[aeroadster]

Members and Experts,

Please advise. I was recently recommended to buy NGK Spark Plugs BCPR6ES-11 for my 1998 2.3 FPT.

The bloke had his own 1996 Aero and claimed he used them in his without any problems.

Can I trust this info or should I be using the BCPR7ES-11 version?

Will I do any long term damage to the engine with these?

Thanks in advance!!!

 

[sgould]

They are the same apart from a small heat difference. I can't remember which way the numbers go

, but they are the same plugs I had on my 98 9-5. On the 9-5 one was standard and the other was recommended as a change if there was difficult starting.

 

[john]

Originally posted by Aeroadster:
[qb]Please advise.  I was recently recommended to buy NGK Spark Plugs BCPR6ES-11 for my 1998 2.3 FPT. [/qb][/b]

It is recommended that you replace spark plugs like for like in order not to shorten lifespan of DI. Also, when fitting a new DI it is adviseable to fit new plugs.

 

[aeroadster]

John,

I don't want to sound too thick and I get what you say about replacing spark plugs like for like, but I've currently got a set of what seems to be Bosch plugs with the model markings worn off so I can't read 'em. It looks as if they've been in there a while so I'm keen to replace them.

I noticed that everyone commends the NGK brand and wanted info on the suitability of the NGK BCPR6ES-11 Spark Plugs over the "7's".

What do you use? Any particular preference?

 

[john]

Who put the Bosch plugs in? Have they been there long?

You really must only use NGK plugs on Saabs equipped with Direct Ignition (DI)

BCPR6ES-11 are suitable for 9000 models without turbo.
BCPR7ES-11 are suitable for 9000 models with turbo.

More info about NGK Plugs and why you should use them.

 

[aeroadster]

John,

I've only acquired the car in the last 2 months.

Looks like they've been in a while and there's no service history with the car for the last two years.

Doesn't appear to be too many probs with starting or general running though. Living in London I spend most of my time stop-starting but have managed to get three or four good 100+ mile runs since I've had it.

I've always owned the original 900 so when the 9000 took 2 seconds to turn and start the engine, I didn't think there's anything wrong.

The car is pretty smooth and exhibits no problems with erratic idling or poor/indifferent acceleration. It's got 86k on the clock and is due for a service.

I have a Pug and had experience of high performance Japanese cars but they've all started with a quicker turn of the key.

Is this bad news?

 

[mark e]

I wouldn't expect the BCPR6ES-11 to damage the DI cartridge per se as they are electrically the same spec as the 7's. However, they are not as good at conducting heat away from the combustion chamber, so you're more likely to suffer pre-ignition which will lead the APC to back off the timing or boost, losing you power.

The DI cartridge will be damaged/have it's working life shortened if the correct spec resistor plugs, gapped properly, are not used.

A set of new plugs will cost about £12. A new DI cartridge is nearer £170. I'd say that was cheap preventative maintenance, and furthermore it's likely to make the car go better

 

[badman]

My 2.0 LPT had a new set of NGK 7s when I bought it. After about 20k it suddenly occurred to me that I ought to change the plugs - even though, as you have found, she started and ran perfectly.

Once I had changed them - what a difference! fuel comsumption went down by about 4mpg and the engine felt like a new lump!

I guess things like plugs degrade over such a long time period that you don't notice a change in the cars' characteristics.

Change em!

 

[john]

BCPR6ES-11 are listed as suitable for 9000 models WITHOUT turbo.
BCPR7ES-11 are listed as suitable for 9000 models WITH turbo.

 

[Dazzel]

If my memory serves me correctly with the NGK spark plug range the higher the number the cooler the plug

 

[Paul D]

Once I had changed them - what a difference! fuel comsumption went down by about 4mpg and the engine felt like a new lump!  [/b]

The service interval for plugs is 30k miles.
However, they need regapping at about the mid point, and certainly by 20k. The gap increases from the 0.9mm (where I set them) to 1.1mm in this timeframe.

By regapping to correct setting you will notice a marked improvement in fuel ecconomy by a approx 3 - 5mpg!

 

[aeroadster]

Great stuff people,

Thanks for the info. The 2.3 FPT is doing an average of 24.4mpg since i bought it. Most of the driving is around London, but I have seeing nearly £20 disappear every week on my limited jaunts.

I'll changed the plugs to the 7-11 type and see if I notice the instant difference. Still no idea what these Bosch things are doing.

Another weekend job