mjsotelo91

Okay, so heres the story
We bought this EG sedan last late summer, and its been sitting since, we have driven it occasionally and kept it up fairly well. We bought the car for around $900. its a 94 EG sedan, stock, previous owner bought it new. We bought it so cheap because the owner said it had a heat issue after traveling a few miles. The owner took it to a mechanic and had the timing belt changed and water pump I believe. The mechanic thought it was a bad head gasket, so that is what we were planning on fixing if that was the problem. Well about 2 weeks ago we got it up and insured and all that jazz. We tested it by going about 12 miles and the heat gauge was fine, coolant levels were good to. So i drove it for about a week and then the gauge went up one day, so i turned on the heat, then it went down quickly. We then got any bubbles out of the coolant and it was fine for a while. then this past week it has been doing weird things, but we know its not actually overheating when the gauge says it is because we can feel the radiator and engine and they are not hot. So yesterday I was driving a lot and the guage was going up really hot, then back down after a few mins. But the thing is when it goes down it drops in like 2 seconds, I doubt the engine heat could go down so fast, also yesterday the gauge was in the red, so i would have a blown engine if it was really that hot, but nothing happened, so we were going to replace the temp sending unit, but now i think there is a slight leak in the radiator or something because yesterday after driving for a while and all that it was down, so maybe the gauge is going nuts when the coolant is down or something? But I think are next move will be the TSU, what do you guys think?...any suggestions on what is making the gauge go wacko?....thanks in advance...

ballinboosi

I would start off and just change the thermostat as that can make your temp gage go nuts plus it's about $8 for that car.

SpeedoKing

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ballinboosi &raquo;</TD></TR><TR><TD CLASS="quote">I would start off and just change the thermostat as that can make your temp gage go nuts plus it's about $8 for that car. </TD></TR></TABLE>

X2 my thermostat when out this winter and it did similar things.

mjsotelo91

I might do that because its cheaper than the TSU, but if it was the thermostat wouldn't the car like actually overheat, we are positive that its not overheating...would the thermostat be easier to replace than the TSU, whats involved with that?, for the TSU I know I would have to take off the distributor?


Modified by mjsotelo91 at 10:03 PM 4/28/2008

SpeedoKing

the thermostat can stick open of closed or back and forth so it is not that unusual. it is pretty easy to do i think there is a write up on it somewhere

mjsotelo91

Ok, me and my bro replaced the thermostat and the temp sending unit, but after running the car for 5 mins the heat gauge was at half, at 10 mins it was more than 3/4...
The lower hose going from the radiator to the thermostat is not very hot at all we noticed, the upper hoses and stuff are hot while that one is not, is that normal? We are thinking maybe the water pump is bad although the people we bought it from said the mechanic replaced that and the timing built, could a faulty one have been put in?...any thoughts or suggestions on what is going on, if nothing is solved then we plan to do a head gasket job...

mjsotelo91

well today the car was getting really hot to and from work, ( like the red line hot!) my dad thinks that the coolant is not flowing through the car, so we are going to take the thermostat out completely and see if that makes it flow, maybe we have a clog or the waterpump is not working? The hose going to the thermostat is not warm at all, like coolant is not even coming out of the radiator or something....any ideas?

mjsotelo91

ok guys my problem is sounding a lot like this guys...how could i test the fan switches and the radiator? https://honda-tech.com/zero...46236

mjsotelo91

Update:
We took out the thermostat today and drove around, it was fine for maybe 15 mins then it started to heat up to about 3/4 then go down to half and then back up again, we parked it and noticed that fan was not coming on, if it was as hot as the gauge was saying we thought it would come on and it did not. We also noticed that the overflow tank filled up quite a bit too. We are thinking maybe there is a head gasket leak and gases are making pockets we also are not sure if the waterpump is working but I don't notice any leaks, any ideas?

mjsotelo91

bump

wonder squirrel

Have a compression test done on it, that will put alot of troubleshooting to rest if you have a head gasket failure.

Also, is the radiator cap holding pressure? If not it will allow the coolant to boil inside the engine and create vapor pockets.

MonkeyMagic

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mjsotelo91 &raquo;</TD></TR><TR><TD CLASS="quote">Okay, so heres the story
We bought this EG sedan last late summer, and its been sitting since, we have driven it occasionally and kept it up fairly well. We bought the car for around $900. its a 94 EG sedan...</TD></TR></TABLE>

headgasket.. there was actually a TSB at honda dealerships back in the ninetys because of the gasket they used on these 1.5 cars.. its a metal impregnated paper gasket rather than the metal gasket they use on EVERYTHING else. they fail from the back of the sealing ring untill one day they finally **** the bed and you get the characteristic white smoke. but untill they finally completely blow out it will over heat while driving or sitting, use some coolant, sometime use none, all kinds of random **** etc etc

but a compression check will nail it down, tho depending on its state of decay it may not be blatantly obvious.. one or two cyl will just be just lower rather than having no compression at all

check it out..

RaWrZie

I have a similar problem.
Once I turn key into the ON position the needle goes straight to 'H' as if it's overheating.
And I can hear the fan go on.

I leave it on for a little while to see if it goes down...and it doesn't.

What could it be?

Thermostat or the Temperature Sending Unit.

('94 Civic EX coupe.)

MonkeyMagic

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RaWrZie &raquo;</TD></TR><TR><TD CLASS="quote">I have a similar problem.
Once I turn key into the ON position the needle goes straight to 'H' as if it's overheating.
And I can hear the fan go on.

I leave it on for a little while to see if it goes down...and it doesn't.

What could it be?

Thermostat or the Temperature Sending Unit.

('94 Civic EX coupe.)</TD></TR></TABLE>

like on a morning when the car is definately cold, you get in and turn the key and the fan goes on and temp gauge goes up?

RaWrZie

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MonkeyMagic &raquo;</TD></TR><TR><TD CLASS="quote">like on a morning when the car is definately cold, you get in and turn the key and the fan goes on and temp gauge goes up?</TD></TR></TABLE>

Exactly like that.

MonkeyMagic

whoa... hmm

cause the fan runs off a switch on the thermostat housing... but the gauge runs off a completely different sensor on the side of the head.

wtf mate? maybe a previous owner tried a fix involving both of them... involving wiring the switch to the guage thereby leaving the fan on (closed circuit) and gauge on hight (low or no resistance, closed circuit)

check for anything funky goin on around the wiring in that section of the engine bay

RaWrZie

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MonkeyMagic &raquo;</TD></TR><TR><TD CLASS="quote">whoa... hmm

cause the fan runs off a switch on the thermostat housing... but the gauge runs off a completely different sensor on the side of the head.

wtf mate? maybe a previous owner tried a fix involving both of them... involving wiring the switch to the guage thereby leaving the fan on (closed circuit) and gauge on hight (low or no resistance, closed circuit)

check for anything funky goin on around the wiring in that section of the engine bay</TD></TR></TABLE>

Sadly...I wouldn't even know where to start looking.
Secondly...I looked through my Haynes Manual and it seems it would be TSU that's [freak]ing up my gauge.
Still need to find out if that's the reason the fan is going on.
Because it thinks it is actually overheating?

Probably a dumb question but I have no idea where to look...where is the TSU?

mjsotelo91

thanks man, thats a good post, that sorta explains it, ya i think its the head gasket too, but all this week I will have to drive it, but only like 4 miles a day, so hopefully it wont give out then....where can i get it compression tested, or a kit? i couldn't find anything online at like autozone but do they have them?...i might try a new rad cap too, but one thing, the fan is not coming on but I saw it come on last week when it was extremely hot, before we put a new thermo and sensor in, so I will have to figure if thats working straight, but I have a feeling its the headgasket thats the main problem....thanks guys, will update later...

mjsotelo91

the ppl we bought it from bought it new from the dealer so if there was a TSB do you think they would have had that taken back and replaced?, but I want to go and get a rad cap and see if that would help at all before I have to drive that tomorrow, I let you know what happens

mjsotelo91

Here is a picture of where the TSU is RaWrZie. The little circled object that looks like a male antenna jack is the TSU... the object squared in red is where the the upper hose connecting from the radiator to the engine goes, you will probably have to take off the distributor (make sure to mark it with a sharpie or a knife) to take out the TSU, thats what we did

RaWrZie

So I open the dizzy to find it?
Pic is too small on my phone but when I get home I'll see exactly what it says.



Modified by RaWrZie at 6:43 PM 5/4/2008

mjsotelo91

no, you just will need to remove the dizzy to get to it with a socket or wrench, its beneath it, do u see the hole above the red circle, that is the hole where the dizzy goes into the engine, did that help at all or confusing?

RaWrZie

Yeah I think that explains it.
Just need to get home to try it.
Wasn't able to see the pic on my phone too well.

MonkeyMagic

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mjsotelo91 &raquo;</TD></TR><TR><TD CLASS="quote">the ppl we bought it from bought it new from the dealer so if there was a TSB do you think they would have had that taken back and replaced?, but I want to go and get a rad cap and see if that would help at all before I have to drive that tomorrow, I let you know what happens</TD></TR></TABLE>

doubt they fixed it, wasn't a well known thing as it took so long for them to finally fail. last one i had was at about 156k and then it really **** the bed... billowing white smoke, it was cool lol

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mjsotelo91 &raquo;</TD></TR><TR><TD CLASS="quote">thanks man, thats a good post, that sorta explains it, ya i think its the head gasket too, but all this week I will have to drive it, but only like 4 miles a day, so hopefully it wont give out then....where can i get it compression tested, or a kit? i couldn't find anything online at like autozone but do they have them?...i might try a new rad cap too, but one thing, the fan is not coming on but I saw it come on last week when it was extremely hot, before we put a new thermo and sensor in, so I will have to figure if thats working straight, but I have a feeling its the headgasket thats the main problem....thanks guys, will update later...</TD></TR></TABLE>

compression tester is just a gauge that threads into the spark plug holes.. prolly like 20 bucks at autozone or somewhere. just unplug the distributer and take all the plugs out.. screw it in and crank the engine a couple times, repeat on all cylinders. that should be enough to let you know.. you may even hear gurgling throught the radiator and **** while its cranking, but i doubt its that bad.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RaWrZie &raquo;</TD></TR><TR><TD CLASS="quote">

Sadly...I wouldn't even know where to start looking.
Secondly...I looked through my Haynes Manual and it seems it would be TSU that's [freak]ing up my gauge.
Still need to find out if that's the reason the fan is going on.
Because it thinks it is actually overheating?

Probably a dumb question but I have no idea where to look...where is the TSU?</TD></TR></TABLE>

whats wierd is the fan is on a completely different circuit from the gauge. so either there is some ghetto rigged fix under your hood that shouldn't require to much to fix properly... or somethings shorted somewhere.

most likely whats goin on, hopefully, its just somethin silly simply

hit us up when you get time to pop the hood and take a look

mjsotelo91

ok, we got the rad cap, but its too hot to put in right now, ya my car is at like 140k