HKS Spark plugs

[Pig]

For all those that have read Alex's spark plug thread, you will know he recommends avoiding HKS spark plugs.

 

As some of you know my car was in @ TDI recently. One of the things done was new spark plugs.

I said, don't put branded ones in, just cheap ones...... ended up with HKS! Typical.

 

I then had some problems with the car and it turned out to be a plug no.1 - these plugs are very new but have suffered some det. All in all a lucky escape, please see the attached pic.

[DamanC]

 

Im sure I read somewhere HKS ones are someone else rebranded.....

[Ric]

are they irridium tipped?

 

Its known when mapping not to use irridum tipped plugs as they disintigrate causing problems (more likely to encounter det while mapping), where as a copper plug would just fail.

 

Im assuming your car had some mapping done? TDI should know this?

 

HKS usually are rebranded Densoplugs

[tooquicktostop]

One of the things I did find with TDI was that they insisted on using HKS for everything and this was almost non-negociable, it makes a big difference with the final bill as well !

 

I am glad you caught it in time

[miko_supra]

 

Im sure I read somewhere HKS ones are someone else rebranded.....

 

I thought hks were just NGK

[Pig]

Denso is written on them

 

And yep, TDI did map the car. With those plugs!

[Ric]

cars shouldnt be mapped with irridum plugs, because of the above they are not resiliant to det

[Alex]

I would get an injector check done on number 1. If it ran lean enough to det whilst the afr gauge was reading normally I would suspect the injectors.

 

I hope no other damage was caused when the plug broke. In fairness to HKS/Denso's that isn't the sort of damage they are famed for. In fact I've never seen the arm break (I would suspect it had been dropped prior to installation). The damage due to det the HKS/Denso's have suffered was the breaking up of the ceramic below the electrode tip.

[Ian C]

It's not just running lean that causes det, too much timing, too hot an intake charge, or a hot spot in the combustion chamber can cause it too.

 

Deffo needs investigating as to why the tip broke though. Maybe it was indeed pre-fractured and just let go. I hope your turbo's exhaust vanes are ok

 

-Ian

[Pig]

I hope your turbo's exhaust vanes are ok

 

-Ian

 

It better be fine, its just been re-furbed.

 

 

A brief description of what happened:

 

I have a cone fuel filter - somewhere down the line, someone opened it up and put the filter part in the wrong way restricting fuel flow. Therefore, everytime i put my foot down it would start to det as the turbo came online. This ruined the plugs that were in there. (there was one occasion where i had my foot flat on the throttle but the car was being restriced, i looked over to AFR's and they were off the scale lean) Lucky my engine survived that.

 

Anyway, we were trying to map and the problem kept happening until eventually we checked the fuel filter and found the fault.

However the new HKS spark plugs had been put in prior to mapping starting. Therefore everytime we tried a run as the fuel pressure dropped massivly the car would have detted (i assume).

 

I took the car on a track once the problem got sorted, then it went in for more mapping (all on these plugs) and i got the car back. It worked blinding well for the first 15 mins or so, and then it started going wrong from there (miss diagnosed my me as RLTC but was actually a miss fire), it got worse and worse until matt harwood suggested changing the plugs and hey presto.

 

So...... Lucky the engine has survived all the debt + the bit falling off. The turbo may be damaged but seems fine.

 

I maybe wrong, but i assume will the miles/mapping done on the plugs that its unlikely it was broken before i started giving it a really hard drive.

 

P.S - TDI are due to call me next week for a "chat" there are certainly a couple of bits that need to be chatted about. Especially there RLTC fitting/diagnosis