kermit_rr · Jan 19, 2025

For petrol it's blue fluid that goes yellow, but the change is instant.. seconds

Graculus · Jan 19, 2025

Can't be instant and seconds....

MrGorsky · Jan 19, 2025

It certianly went yellow pretty quick.... still, no rain forecast for Saturday at least.

Grrrrrr · Jan 19, 2025

Graculus said:
Can't be instant and seconds....

Maybe the change starts instantly but takes a few seconds to complete?

The v8 probably kicks out more gases!

kermit_rr · Jan 19, 2025

Graculus said:
Can't be instant and seconds....

If it's less than 5 seconds, that's pretty instant to me.
Less than 10, that's a few

Datatek · Jan 20, 2025

Grrrrrr said:
I'd noticed the car was no longer losing coolant but the hoses seemed too hard to me. Yesterday a sniff test kit arrived and today I tried it. Fluid starts red and turns yellow with 5 minutes if it detects exhaust gases. In my case it went yellow in 2 minutes.

So it looks like the head gasket has failed. Just need to find the time to do it now ... and the money for ARP studs.

Cracked head

Grrrrrr · Jan 20, 2025

Datatek said:
Cracked head

Bloody hope not. It was brand new 2 years ago. Of course, the wife driving it with no coolant won't have helped.

Datatek · Jan 20, 2025

Grrrrrr said:
Bloody hope not. It was brand new 2 years ago. Of course, the wife driving it with no coolant won't have helped.

How did she drive it without coolant? They go into limp mode PDQ as I found out when the plastic water pump failed.

Grrrrrr · Jan 20, 2025

Datatek said:
How did she drive it without coolant? They go into limp mode PDQ as I found out when the plastic water pump failed.

Manual box doesn't seem to do that. Or mine is so old it doesn't. Or she just carried on anyway.

RangeRoller dt · Jan 20, 2025

No 3rd sensor on early dt. Mine did go into limp mode but not straight away. BECM does iirc? It was more than 10 seconds so more than a Kermie-instant. 3-4 mins.
That was with a huge gaping hole in rad when pump blew. Little to no coolant no pump or fan even present and belt was long gone. Kept driving it to a safe place to stop so it cut out few times with overheat shutdown. was no subsequent issue with head cracking or anything on 150,000 mile engine. Could just be luck though. Your Sniff test suggests it’s atleast the gasket perhaps head itself is fine

Datatek · Jan 20, 2025

RangeRoller dt said:
No 3rd sensor on early dt. Mine did go into limp mode but not straight away. BECM does iirc? It was more than 10 seconds so more than a Kermie-instant. 3-4 mins.
That was with a huge gaping hole in rad when pump blew. Little to no coolant no pump or fan even present and belt was long gone. Kept driving it to a safe place to stop so it cut out few times with overheat shutdown. was no subsequent issue with head cracking or anything on 150,000 mile engine. Could just be luck though. Your Sniff test suggests it’s atleast the gasket perhaps head itself is fine

Limp mode is from the EDC via the EDC coolant sensor but if no coolant in the head, it will not register an overheat.

Grrrrrr · Jan 21, 2025

Datatek said:
Limp mode is from the EDC via the EDC coolant sensor but if no coolant in the head, it will not register an overheat.

I wonder what temperature it is set to?

I've seen my temperature go to max with the red light on and no difference in performance. Maybe it has to be up there for 5 minutes as RRDT implies.

Datatek · Jan 21, 2025

Grrrrrr said:
I wonder what temperature it is set to?

I've seen my temperature go to max with the red light on and no difference in performance. Maybe it has to be up there for 5 minutes as RRDT implies.

I don't know on the old one's but both mine went into limp mode PDQ when the gauge went into the red.

RangeRoller dt · Jan 21, 2025

severe power loss more than pulling your MAP off. Not something you wouldn’t notice. Maybe it didn’t function for some reason? Or maybe mine was ultra cooked

Grrrrrr · Jan 26, 2025

OK. Head and block all seem straight. Cylinder head gasket shows slight sign of blow on cylinder 6. I'd heard Reinz gaskets were a little suspect recently and this seems to confirm that.