Intermittent pinging.

[CEF33Y]

Hey guys.

Have an issue with my r33. Lately (last 2 tanks) has been Randomly pinging/ knocking on boost.

When I first heard it, backed off straight away. Temps seemed fine and was driving fine off boost, almost as it hit full boost, would ping. 
Suspecting shit fuel, put in some octane booster, and that seemed to fix it. 
Fueled up at a different servo, and was going better than ever, zero knocks. Put it down to shit fuel.
 

Current Tank is about 1/4 full, rolled on in third coming home tonight and it pinged again.

Car drives fine, and exactly the same everywhere else, no strange noises, temp is fine.

Car has a Vipec plugin, deutchworks 255l/h fuel pump with 14v feed, splitfires, hyper gear turbo, pretty basic setup. 260ish rwkw,  Tuned by Mitch (of haltech)

Car has been the same for the last 2.5 years, parts were new (apart from ecu) at tune time.

Both times it’s happened now, it’s been between 1/4tank and a 1/3 tank of fuel, unsure if that’s linked. Initially thought maybe a shit fuel pump, but thought that would be more consistent

From what I gather the Vipec plug ins don’t have knock protection? Either that if mines not setup. 
 

Will have to head back to tuners I think. I’m guessing if I can hear knock, it’s probably already doing damage. 
 

After first tank with knocking, pulled plugs out (all looked normal) and did compression test, 165-170 across all 6. Top of pistons looked unmarked.

 

Bloody intermittent issues! 
Anyone had a similar intermittent knocking issues/things I should check?

 

Cheers
 

 

 

[Duncan]

assuming it is not overboosting....

I would change the fuel filter and if possible check fuel pressure under load. 

[CEF33Y]

On 12/2/2021 at 6:46 AM, Duncan said:

assuming it is not overboosting....

I would change the fuel filter and if possible check fuel pressure under load. 

Not over boosting, boost control is setup through ecu, but have a gauge with recall, I’ve seen 21-22psi before. When it pinged, didn’t get there, was around 17psi.

Yep that’s the train of thought I’m on. (Fuel supply)

Will sort out a fuel pressure gauge, I think my Defi meter has provisions for another pressure sensor, will also check voltage getting to pump.

 

Thanks

[Duncan]

If you have oil pressure gauge already plumbed up you have the option of plugging the oil sender port (generally 1/4 BSP) and then plumbing the sensor into the fuel feed to the rail, you would need a T fitting (2x 5/8th barb and 1x 1/4 BSP) which are readily available

[Dose Pipe Sutututu]

Or just install a wideband, and also set it up for closed loop O2 control (for future).

Good to see what your fuel mixtures are at

[CEF33Y]

Thanks guys,

Yes I have a spare input and pressure sensor, will set it up for fuel pressure and see what its doing.

 

 

[Lithium]

Have you upgraded your CAS setup? There are various options but an aging RB25 and knock on boost has a definite trigger error feel to it 

[joshuaho96]

On 12/3/2021 at 1:38 AM, Lithium said:

Have you upgraded your CAS setup? There are various options but an aging RB25 and knock on boost has a definite trigger error feel to it 

Easiest way to test is try a fixed timing test like 15 degrees regardless of load/RPM, get a timing light on it and see how much it jumps around while you rev. Load doesn't really affect timing scatter.

[Lithium]

On 03/12/2021 at 11:25 PM, joshuaho96 said:

Load doesn't really affect timing scatter.

Of course not, but knock becomes a lot more likely if you introduce boost to a setup which has erratic timing 

[CEF33Y]

Stock (old!) CAS, 

It is very inconsistent. will try the timing check and see what I can find.

Thanks

 

[joshuaho96]

On 12/5/2021 at 4:56 PM, CEF33Y said:

Stock (old!) CAS, 

It is very inconsistent. will try the timing check and see what I can find.

Thanks

 

If the timing check shows timing bouncing all over the place despite commanding a fixed value in the ECU then the most likely explanation is either the CAS drive pin on the cam has worn, the CAS drive gear has worn, or both. I suspect a number of the more severe cases of timing scatter are actually due to this issue.

[Lithium]

On 06/12/2021 at 1:56 PM, CEF33Y said:

Stock (old!) CAS, 

It is very inconsistent. will try the timing check and see what I can find.

Thanks

 

let us know how you get on