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99SVT3753
08-28-2006, 09:16 AM
So normal cars knock when they are cold until the pistons or rods heat up and swell and take up the 'empty' space.

My car lately runs AWESOME until it gets to operating temp (it was wanting to overheat but I watched it and shut it off as I was driving). I pulled the thermostat to help keep it cooled off. Replaced a hose at the back of the block that looked like it was collapsing upon itself.

I can let it run all day in the driveway but as soon as I start driving (from cold) and put a load on it, it'll want to knock. If I drive it too long, the KNOCK SENSOR code shows.

I feel coolant flowing, but maybe it's not enough?

Once I let the car cool down, it runs great again until it gets to operating temp.

Nothing blows out the exhaust - I punched it HARD a few times trying to get something to show while a friend was following me.

Can it still be a bad head gasket? (Comp Test shows all norm)
Most likely bottom end? (maybe oil is too thin?)(Timing?)
Should I swap the water pump out to my Cobra one just to test it?

Any help would be greatly appreciated as I'll have a 4 day weekend next weekend


Tim

dewone
08-29-2006, 08:33 AM
I would concentrate on the hose that was collasping. It may not be the hose it's' self. It could be there's a partial blockage or a clog before the hose. That could mean certain areas of the engine are not flowing coolant. The pump may or may not be the actual problem with the hose collasping it shows that the pump is creating a vacuum in the line hence I suppect a clog.

99SVT3753
08-29-2006, 08:51 AM
Makes total sense to me. I'll look into that. Thanks a million!

Tim

SNAKEYE
08-29-2006, 12:41 PM
Did you properly "burp" your baby when refilling the cooling system after the hose replacement?

smashedheadcat
08-30-2006, 07:13 AM
Uhh...... Not sure what that might be. Where does the knock sound like it's coming from??

Check the PCV valve maybe?

99SVT3753
08-30-2006, 09:58 AM
Did you properly "burp" your baby when refilling the cooling system after the hose replacement?
Ya .. 3 days I let it run and filled up the res as it went down and watched air bubbles.

Uhh...... Not sure what that might be. Where does the knock sound like it's coming from??

Check the PCV valve maybe?
Sounded like Crank - but you could hear it outside the car near the clutch - so I pulled it back out and redid it thinking it was kinked or broke a bolt or something.

EGR was deleted, but I still have the PCV attached to the valve covers cuz everyone was talkin about trapped gases and all that - and PCV checks good. thanks for that one!

Someone on Modular thinks it could be the tune - cuz it is prolly too lean .. so at cold when it adds the extra fuel, it runs good .. then as it gets warmed up and it takes the fuel out, then it starts "exploding" due to the lean condition instead of "burning".

So I'm gonna install the 42# and 90mm MAF and update to see if it likes that better.

Thanks all!

Hope to have it narrowed even further this weekend!

Tim

99SVT3753
09-05-2006, 03:29 PM
Compression test showed all good .. leak down test showed #8 at 3% holding (97% loss) .. had the intake off at the time and physically looked down and saw 1 of the Intake valves stuck open.