Alright so heres the scoop a6 head....and mpfi conversion...Im throwing 1 code...actually a code 1....for o2 sensor its bad.....

After about 10-15 min. of driving car over heats.........I changed the T-stat today....fan kicks on by itself......and I have enough coolant and water in my system....

Just a ?....is there a chance I have air trapped in my motor ive used the heater often to keep it cool which should have drained the air and when the car runs the coolant lines are pressurized...well you can hear the coolant in them when you sqeeze them.......

wheres the coolant bleed bolt at that is says but doesnt show in my chiltons??

BTW: im using a thicker then stock OEM headgasket and its torqued down correctly....but I bought a better torque wrench today so im going to check on that.....as well as a leak down test and a compression test....

BUT...heres the weird thing my ****** temp gauge tends to go up and down easier like a bad sensor or bad reading....it will go up and down.....really fast...or it will get hot...then come to a stop and it will cool.....and so on......but im not throwing a code....is there a chance somthing is not getting read right??

 

It's easy to check for air in the system. There are two ways to do this. You can simply take off the rad cap, let it warm up, then squeeze the hose over and over and air bubbles should come out. Or you could just unscrew the release on top of the thermostat housing. I prefer the first method though.

It is also possible that you have a blockage in one of the cooling passages in the head.

 

i like using the first way also, just keep squeezing the upper hose and the coolant level should keep going down little by little, make sure at the end you fill it up again

 

What about your radiator?

 

Question: Did you remember to put the dowels in your new a6 head?

I bet you didn't. I had the EXACT same problem when I swapped a z6 head onto my a6 block(mini-me). What happened was I forgot to put the dowel pins in the Z6 head to center up the head, headgasket and block like they should be. It would be ok at idle, but if I revved it or drove, it would overheat almost immedately.


[Modified by Speed PHreak, 10:26 PM 9/9/2002]

 

Dowels....Ive got one in...the front passenger side one....and all the other bolts lined up fine.....I just couldnt pull the other dowel outta my DX head but one stayed in the block....so I put it down on the dowel...(BTW used 3 people to put on head becuase I funked it up the first time)

put all the bolts through and everything lined up okay...and nothing is leaking outta the block/head...and im burning nothing(okay just a lil oil....it always did though)

Okay on my upper radiator hose by the head there is a bleed screw/nut I turned it while it was running as the manual stated and it let out quite a bit of air until coolant completely drained to the top then I tightened it....the car ran pretty good like that, I drove the car to work about 20 min. away on the highway and she did great until about 1/4 the way there she got hot again....but tonight on the way home....It ran GREAT....it ran about right in the middle of cold and middle...and until I got into my neighborhood she started to get a lil hotter...so I got home...and tried to bleed that screw some more.....but it had been done enough.....but she idled okay at about 1/4 the way up to middle....

but I noticed now when I start to slow down or break it would go up...but if I give it gas it would go down.....I think the system needs pressurized....

Oh BTW...on the way to work my CEL came on.....pulled over and checked it.....VSS sensor is blinking as well as the same 02 sensor....what is the VSS going to affect...my speedometer is working fine....

 

did you **** up the gasket? like nick it or a dent in it will mess it up.i did this on a accord one time years ago.i put a nick on the oil jet copper ring,i thought it be allright and started it and had oil leaking all over the back of the block.had to put on a new one.


[Modified by 4gvtec, 5:06 AM 9/10/2002]

 

No I already did that once....exact same problem...had a krappy feel pro gasket this time I had a 4 layer this *** metal gasket from honda......and it all went on fine....

Im going to retorque my head well chck the specs tomorrow...and mess with teh pressure some more I think im figuring it out.....

 

when your car gets hot and then cools down fast..... do u have a termastat in there.... ... and is the timing write ... also are u using a good raditor

 

Do you mean like do I have a manual one to see what my temp is at?? I just bought a brand new one and put it in...and its working becuase obvouisly im getting coolant flowing throuagh all my lines...

Guys in all honesty my friend said to me the other night...."dude, maybe your ECT sensor is okay but the wire to the gauge is screwed up.....like the gauge itself is bad"

and I kinda agreed with him becuase ive never seen a h/c gauge fluctaute as much as mine can once it starts to get really hot....but you get out of the car oh say after driving half an hour....im burning absolotulely nothing and my engine stillfeels actuall very cool.....

Im not to sure....I may make the fan switch work so that I can have it on whenver I want.....I checked my fins on the radiator and it seemed fine....Ill pressureize it this morning but in all honesty I could just have a fualty gauge....

Oh well Im getting my valves adjusted by honda tomorrow so I might mention it to them and ask them what I should try??

 

Dude, i'm telling you it's those dowel pins in your head. If you've only got 1 the you head gasket is prolly misaligned between the block and head. Those pins are ment to center all 3 componets up. The small amount of play that is aounnd the bolt holes in the headgasket will allow it to shift around on the head. The gasket will actaully overlap into the cylinder and not seal properly. I've had the EXACT same problem.

Do this, start your car and take your radiator cap off before it gets warm. let the car idle and warm up. When the guage says the car is "warm" go look in the radiator fill spout for bubbles. Give the engine a couple of revs and watch for bubbles. If you get bubbles then your headgasket is leaking into your coolant system.

I thought it would be ok without the dowel pins but the fact is they need to be there to align the headgasket right. The reason the guage fluxuates like that is because it is right in the water jaket around the cylinders, so it has a quick reaction time to the temp change in the coolant.


[Modified by Speed PHreak, 2:23 PM 9/10/2002]

 

reply okay well I have the dowel pin....but how do I get it outta my old DX I swear its like lodged in there.......

???

 

wd-40 and some pliers, with a GENTEL twisting motion back a forth. When the dowel starts to twist freely, apply a slight upwards pull with each twist, youll gradually work the dowel up and out. Don't be to rough with it or you'll maul that dowel up till it's unusable

 

Well I suppose thats my problem....bad thing is I have to drive all the way to ****** chicago( I live in des moines ia) this sat....to start school.....lol..but Im getting it towed on my roomates flatbed a long with his unfinished crx......

But I also figure.......hey...if it gets a lil hot...it should be okay right??? I mean nothings leaking outta the headgasket...and if its only a water jacket then it is prob. still cooling the engine just not its fullest.....

I plan on swapping in a new motor once I get my feet on the ground in chicago....Id like to have a b16 but with money constraints and all Ill prob. just get a ZC..since im already for one....mpfi conersion and all......plus I have a si tranny on hand....

 

If you overheat it enough you'll wrap the head, don't be a retard fix it now.

 

k this happened to me after Z6 swap.. dont knnow if it might be happening to you......
the hose that goes from under the intake manifold to the block...... makes like a U shape... i use a regular hose... on the curve the hose bent.... water wasnt flowing.... so the hot water was staying on the block and since the temp sensor its there, was reading my car was all the way to red..... on the front the temp was ok and cool.......... i change the bent hose, for a better one and since its not pinched anymore it doest get hot,,,,,, make sure ALL ur water lines are ok and not pinched......just a pointer that goes without notice sometimes......