94 Q45 head gasket

[kevinpaigeking]

car is overheating. mechanic says radiator needs replacing. idle is rough, and he says i might have a head gasket breach, causing back-pressure. no white smoke, no water in oil. If so, does this steel seal stuff work? check engine light is not on.

[Trumpkin]

Steel stuff?

[qship96]

Head gasket leak ? Time for a new engine or entire car{which is cheaper and easier}

[Q451990]

Your mechanic is guessing. Head gasket failures are very rare except in cases of extreme owner abuse (multiple major overheats). I'm going to guess that you're overheating due to poor cooling system maintenence - replace that radiator and whatever else is wrong. Then check your injectors, MAF, fuel pump, etc. for the rough idle.

Avoid any "cure in a bottle" unless you're trying to limp the car to the dealership for a trade-in. Anything that seals small gaps can't be good, no matter what the bottle or the guy at the parts store tells you.

Heath

[maxnix]

One must maintain everything or failures will cascade to a calamitous end!

[kevinpaigeking]

had radiator and waterpump replaced. idle is still rough and 1st gear acceleration is weak. Also, once in 4th gear, power over 80mph seems restricted. check engine light came on today but went away on restart later. advice?

[qship96]

must read codes to know where to begin. Overheats frequently destroy the knock sensors which will cause engine management system to retard ignition timing to protect engine from detonation- this could be part of your issue, but I think there is more going on here.

[kevinpaigeking]

I had ks replaced this year. could one short over heat kill them?

[qship96]

yes- easy to check codes that will tell you for sure if they are still working correctly or not.

[maxnix]

I had ks replaced this year. could one short over heat kill them?

Easily! Check them through the harness.

[kevinpaigeking]

just checked codes. getting a 34. reset and started over, got a 55. then reset and read again, got a 34. I am sure knock sensors need replacing, but my idle and acceleration are terrible. It feels like I am running on less than 8. How do I check coils easily?

[kevinpaigeking]

I had my waterpump and radiator replaced. a few days later i say coolant trying to escape from radiator cap. replaced cap. temp gauge has never risen above 1/2. after driving for about 45 min, especially on freeway, car begins to jerk on acceleration. as i back off on gas pedal, car smoothes out, and sometimes allows me to accelerate. upper radiator hose looks like it has pressure. why would my temp gauge not rise if cooling system is running hot? if so, could my transmission be over-heating, causing this bucking/jerking?

[Q451990]

If your temp. gauge is only rising to 9 o'clock, let's assume your cooling issue is solved.

Your knock sensor issues can cause bucking at lower RPMs (such as at cruise on the interstate) if you have other issues like a dirty plenum, throttle body, EGR, etc. A bad mass air flow (MAF) sensor or bad fuel pump or fuel pump control unit could also cause it.

Heath

[kevinpaigeking]

why does it take 45 min to appear? which of these would cause pressure on upper radiator hose?

[Q45tech]

How much pressure It is normal to see 10-13 psi sometimes.Study max temperature spec on KS. the plastic housing cracks easily and fast when temp exceeds 275F............which is easy to reach if you overheat then turn off with hood closed!

Remember all aluminum engines are much more finiky and demanding than cast iron or mixed units.Anytime temperatures climb beyond the normal range, the engine is running in the danger zone.

http://www.aa1car.com/library/overheat.htm

[Q451990]

why does it take 45 min to appear? which of these would cause pressure on upper radiator hose?

Not sure what you mean by pressure on the hose... is it swelling above it's normal size? The hoses should feel stiff when everything is warmed up.

The length of time to appear could be something electronic that's temperature sensitive (as in MAF)

Heath

[Jesda]

NEVER USE THE HEAD GASKET IN A CAN. YOU'LL ONLY GUNK UP THE MOTOR AND GET A MONTH OF USE OUT OF IT.

[M45Runner]

NEVER USE THE HEAD GASKET IN A CAN. YOU'LL ONLY GUNK UP THE MOTOR AND GET A MONTH OF USE OUT OF IT.

Well, this is an extreme situation and I have heard of lots different stories. One of my friends had a head gasket leak and used this stuff, the problem was fixed and he had put over 60K on the same motor / radiator over the last 5 years. Car is still running strong as of today.