AU XR8 series 3, 5 speed manual

Edxr6 · 12-09-2023, 10:24 AM

Guys,

When I am under acceleration especially on the incline, the car will miss, at the same time I can hear like a squeal/screech noise from the motor. Any thoughts, I have no idea at this point in time. I will do a scan check for any fault codes, hopefully this Saturday.

Cheers

**PG2** · 12-09-2023, 11:12 AM

Harmonic balancer.

Edxr6 · 12-09-2023, 06:22 PM

Quote:

Originally Posted by PG2

Harmonic balancer.

Will the Harmonic Balancer cause the miss, it’s just the one miss. Also there is no vibration what’s so ever with the motor.

**aussiblue** · 12-09-2023, 06:45 PM

Quote:

Will the Harmonic Balancer cause the miss, it’s just the one miss. Also there is no vibration what’s so ever with the motor.

Yes, as it slips the timing goes out.

See:

https://dannysengineportal.com/harmo...warning-signs/
https://fluidampr.com/troubleshootin...nic-balancers/
https://automotiveden.com/harmonic-balancer/
https://www.techtips.ie/Gates/torsio...on-dampers.pdf
https://www.underhoodservice.com/har...ers-fail-look/

and Youtube on how to replace it.
https://www.youtube.com/watch?v=hoI9Znd8m18

Etc

290GTP · 13-09-2023, 07:14 AM

The fuel pump on my s3 XR8 would screech on occasion. Will also cause a miss.
Just a thought

Edxr6 · 13-09-2023, 11:31 AM

Quote:

Originally Posted by aussiblue

Yes, as it slips the timing goes out.

See:

https://dannysengineportal.com/harmo...warning-signs/
https://fluidampr.com/troubleshootin...nic-balancers/
https://automotiveden.com/harmonic-balancer/
https://www.techtips.ie/Gates/torsio...on-dampers.pdf
https://www.underhoodservice.com/har...ers-fail-look/

and Youtube on how to replace it.
https://www.youtube.com/watch?v=hoI9Znd8m18

Etc

Thanks Aussiblue, good bit of information. I will let you guys know of the outcome.

Edxr6 · 13-09-2023, 11:36 AM

Quote:

Originally Posted by PG2

Harmonic balancer.

Thanks PG2, interesting. I was more thinking of spark plug or leads. Nevertheless I am no mechanic or pretend to be one, hence this wonderful forum full of knowledge and experiences.

Cheers

Edxr6 · 13-09-2023, 11:37 AM

Quote:

Originally Posted by 290GTP

The fuel pump on my s3 XR8 would screech on occasion. Will also cause a miss.
Just a thought

Thanks 290GT.

Edxr6 · 28-01-2024, 10:28 AM

OK, update. Replaced the Harmonic Balancer and the problem still exists?

Regards

**mad2** · 28-01-2024, 11:43 AM

Quote:

Originally Posted by Edxr6

OK, update. Replaced the Harmonic Balancer and the problem still exists?

Regards

as in one or both of the faults you mentioned?.

Quote:

the car will miss, at the same time I can hear like a squeal/screech noise from the motor.

T3rminator · 28-01-2024, 12:33 PM

Missing when engine is under load (incline for example) could be a vac leak. If you get a lean code when scanning, then that increases the probability that its a vac leak.

As for the noise, a video can sometimes be useful to assist with internet diagnosis

**DFB FGXR6** · 28-01-2024, 06:00 PM

Quote:

Originally Posted by Edxr6

Guys,

When I am under acceleration especially on the incline, the car will miss, at the same time I can hear like a squeal/screech noise from the motor. Any thoughts, I have no idea at this point in time. I will do a scan check for any fault codes, hopefully this Saturday.

Cheers

Quote:

Originally Posted by Edxr6

OK, update. Replaced the Harmonic Balancer and the problem still exists?

Regards

Look into the camshaft synchronizer, which have a habit of becoming noisy like that and cause misfiring. A very common Windsor issue, but also other Ford V6 engines. You can lubricate them, but the effect is short lived and replacement is the best option.

https://automotivesuperstore.com.au/...SABEgJ79vD_BwE

https://www.autopartssupply.com.au/f...CABEgLPg_D_BwE

**Peuty** · 28-01-2024, 10:01 PM

^^^this - the screech is a good sign that it’s the issue.

Simple enough job to do mate,

undertow · 29-01-2024, 11:30 PM

Most likely the cam synchro as above, for a test or temporary workaround you can unscrew the black cap and tip a teaspoon of engine oil down there.

Back in the day people used to buy them from rock auto in the states, but there are local options now. The very last year or two of the 5.0 explorers had the same part. The Dorman one was dirt cheap but regarded as poor quality with several tales of the gear stripping or falling off and destroying the engine. I haven't keep up recently, but the genuine Motorcraft part would be the safest bet if it's still available.

Edxr6 · 30-01-2024, 09:18 AM

Thanks Undertow,

B.P.T Motorsport are selling the factory Camshaft Synchroniser's for a ridiculous price of $482, nevertheless there are quite a few on the market now. But I will try the oil treatment first, this will at least be a good indication it's the Camshaft Synchroniser, if the problem subsides temporarily.

Regards

raised by monkeys · 30-01-2024, 02:15 PM

I ordered mine from the US years ago, delivery for under $130 i reckon

**fordomatic** · 30-01-2024, 04:15 PM

They are still cheap, I got one recently from my parts guy for $145.

**PG2** · 30-01-2024, 11:55 PM

Sorry Edxr6 that I lead you up the wrong path.

I should have said to check it first.

Edxr6 · 31-01-2024, 02:01 PM

All good PG2,

It would have needed to be changed in the near future I guess with 180,000klm on the clock. Most of the engine components are all factory, except the valve springs and retainers. They were only changed out because I had the common problem of a cracked valve spring and went with the heavy duty Crow set up.

I am guessing all the mechanic moving parts on these motors are coming to age and soon require replacing, it's all part of ongoing maintenance.

Cheers