Wrong Spark Plugs For 60,000 Miles (D4 Vvt-I T4)

[Avensis Avenger]

Dear Comrades,

I have an Avensis T4 Estate - a D4 vvt-i 2.0 (2005). it is an AZT250W which means it has a 1AZ-FSE (direct injection) engine.

It has done 120,000 miles. I recently found out it had been running on NGK IFR6T11 Iridium spark plugs for the last 60k which are for the 1AZ-FE (non direct injection) engine.

I bought the car when it had 70K on the clock and just had the plugs changed. The car hasn't given me any particular grief. I have had a number of oxygen sensors go wrong and get 20mpg around town but expect that is normal for such a car.

Question: MIght running these non-direct injection plugs have had a negative impact on the car in any way (short term/ long term/ fuel consumption/ engine damage etc)?

For reference, the 1AZ-FSE should have NGK HB6AIX-11Ps Iridums, or Denso/Toyota 90919-01230 (not 90919-01221 or 9019-01210) SK20BR11 (not SK20BGR11 or SK20R11).

[Konrad C]

I went to the NGK UK site and could not find any extra individual details, regarding the spark plugs. You will need to contact NGK themselves.

Whilst visiting the site, which I assume have you have done too, I checked the compatility and other info. Yes they do show the two versions you mentioned.

Check the following links I found:

http://www.ngkpartfinder.co.uk/car_commercial_search.php?type=SPARK%2520PLUGS&manufact=TOYOTA&model=AVENSIS%25202&engine=2.0

http://www.ngkpartfinder.co.uk/cross_reference_search.php?part=SK20BGR11&type=SPARK%20PLUGS&manufact=DENSO

http://www.ngkpartfinder.co.uk/cross_reference_search.php?part=90919-01221&type=SPARK%20PLUGS&manufact=TOYOTA

http://www.ngkpartfinder.co.uk/cross_reference_search.php?part=90919-01210&type=SPARK%20PLUGS&manufact=TOYOTA

http://www.ngkpartfinder.co.uk/cross_reference_search.php?part=90919-01230&type=SPARK%20PLUGS&manufact=TOYOTA

From the cross reference findings above, NGK seem to conflict with your post. Who is correct?

Regarding the incorrect spark plugs, if they have not suffered any damage, then the engine will be fine. All they do is conduct the spark to the electrodes.

I think you may get slightly improved economy at best, when you install the correct spark plugs.

[Avensis Avenger]

Thanks Konrad.

Indeed I had checked the NGK spark plugs site which confirmed to me that the ones they pulled out (IFR6T11s) are the owrong ones for my car.

The two that come up for my car on NGK parts search are:

1. AVENSIS 2 2.0 1AZ-FE / VVT-i (Not Direct Injection) 01/03 –> IFR6T11 4589

2. AVENSIS 2 2.0 1AZ-FSE / VVT-i (Direct Injection) 01/03 –> 12/09 HB6AIX-11P 5703

I have a 1AZ-FSE D4 Direct injection so the latter is the correct one for my car (the HB6AIX-11P), and not the IFR6T11.

Hopefully the new plugs will give me slightly better fuel efficiency as you say - saving me a few bob.

Thanks again.

[Parts-King]

All this talk of NGK................It should have Denso plugs in it

90919-01230 is the right one from your dealer or SK20BR11 from a Denso supplier

Kingo

[Konrad C]

All this talk of NGK................It should have Denso plugs in it

90919-01230 is the right one from your dealer or SK20BR11 from a Denso supplier

Kingo

Kingo,

You are right.

I only use Denso myself.

If NGK supply the wrong info regarding compatible plugs, they cannot be trusted. At least with Denso you are getting the correct plugs.

Also what is the price difference?

Konrad

[Avensis Avenger]

Hi Konrad and PartsKing,

Indeed - had the job done a couple of days ago. I had the garage replace the (wrong) NGKs (that had been put in at 60K when the car was owned by someone else) with Densos (90919-01230 SK20BR11) as I too was a bit shaky about straying from Densos. The garage recommend NGK but I insisted on the Densos.

I had asked for Denso 90919-01230 but initially the garage mistakenly fitted 90913-1210s. I recognised the error on Wednesday (saw the wrong codes on the plug boxes) so requested that they be replaced and the garage were good about it and did them straight away - I am luck to have a good independent garage.

No noticeable difference as yet - i'll have to see over the next few thousand miles.

Thanks again.

[t-spiritpete]

All this talk of NGK................It should have Denso plugs in it

90919-01230 is the right one from your dealer or SK20BR11 from a Denso supplier

Kingo

Kingo,

You are right.

I only use Denso myself.

If NGK supply the wrong info regarding compatible plugs, they cannot be trusted. At least with Denso you are getting the correct plugs.

Also what is the price difference?

Konrad

Konrad,

it goes without saying Kingo is always right .... he's in the trade and he comes from sunny Cheshire!

Pete