Something Weird Happened - compression test results

[fred130111]

Pretty much going along a motorway when all of a sudden the engine light came on.

So instantly pulled over into the nearest lay by and then inspected the engine bay.... Nothing obvious wrong.

So turned it back on and the temperature flew up instantly, so I turned it off and looked for a leak, nothing. At this point I am thinking WTF.

Anyway pulled the coolant cap ( as expected it sprayed everywhere ) Luckily I had a big container of water to top it up after, Not enough to fill it up though.

Wasn't that far from home so just started it an continued to go home, engine light was no longer on but temperature kept going up and down. When I got home I bled it all through with coolant and has since been fine.

So I am confused, 1. what could possibly set the engine light off? ( Checked for codes and nothing stored )

and 2. I am assuming there must be a leak or when I originally filled it up there was a massive air lock?


Thanks in advance for any help!

[mr2magic]

Pull the code. You'll probably find it was knock and you have now blown the stock HG.

[fred130111]

If I had blown the head gasket wouldn't it be overheating now? Seems to be fine after topping it up etc however on initial startup it is fairly smoky but put that down to the cold weather.

Funnily enough I normally use 99 ron but had to put in 95 as was running low, could this have caused a knock issue?

This is looking bad now as just pulled the oil cap and looks like some ones taken a runny sh!t on it........

[fred130111]

Checked the dipstick and the oil is normal colour?

[mr2magic]

I originally overlooked that you pulled the codes but none were stored.

I still think your HG is blown. This usually presents itself after prolonged hard driving where a sufficiently large bubble increases system pressure and causes one region of block or head to overheat and so compromise the whole cooling system.

If the oil cap is filled with a brown sludge it's almost certain to be HG.

Re the dipstick...if you put oil in water what happens...it floats. Any coolant mixed in with the oil will be at the bottom of the pan. Pulling the dipstick out will merely pull it from the coolant through the oil.....you wouldn't notice any water there at all unless theres so much that it also starts to look like your oil cap

[fred130111]

hmmmm thanks for the advice, I would have thought with this kind of issue I would get a loss in power? no loss in power at all, It idles normal etc as well.

Yeah the Sh!t in the oil cap just looked like a little bit of brown water, not much at all. I have seen much worse on other cars and it turned out to be cold temps outside causing it.

I guess I will have to see over the next few days

[mr2magic]

If you can flush the coolant completely, refill and the go for a prolonged spirited drive. If it overheats....HG.

[fred130111]

Certainly will try that Thanks

[fred130111]

Spirited drive complete and no sign of overheating at all.

Checked for stored codes again as may have not done it correctly before and it came up with 22 water temp sensor signal.....

Does this mean I could have a dodgy sensor? It was changed a few months ago with a cheap one from euro car parts


Cheers

[androo007]

Normal for a bit of brown sludge on oil caps in winter, just condensation with it being cold. Had it on pretty much every car I've ever owned!

But......water must have been low for a reason.

[mr2magic]

Could be a faulty sensor. As to the brown sludge, I've never had it on any car..ever!

[fred130111]

Hmmmm that's what I'm thinking, the thing is the engine light came on before the temperature went above normal, that's making me think a screwed sensor.

The trouble is the slightly smokey exhaust is a concern but at the moment putting that down to the cold weather, under hard acceleration there is no smoke, just when it's sat on idle. As for the sludge well there wasn't any sludge as such it was more like a small bit of wet brown juice.


Thanks for your help

[fred130111]

Anyone got a compression tester in sussex that would be willing to help? need to put my mind at rest with this as getting such a varied response from people

[fred130111]

Ok so just had a compression test at a garage, not sure it was done correctly as the throttle was not fully open ( there was no throttle being applied ) and the efi fuse was not taken out....... But these are what it showed

Cylinder 4: 150 psi
Cylinder 3: 150 psi
Cylinder 2: 145 psi
Cylinder 1: 140 psi

These seem pretty low for a 3sge but could this be due to the test not being performed correctly? Also is cylinder 1 anything really to worry about? I was told allow between 10 and 15% ?


Thanks!

[masterbateson]

What are the figures for our cars? is there a known reccomended/ideal level in the BGB for instance?

[MartinF]

What are the figures for our cars? is there a known reccomended/ideal level in the BGB for instance?

Yes

[CalMac]

http://www.imoc.co.uk/forums/kb.php?mode=article&k=15