help! SE running like crap!

alright.. well i finally got around to putting the exhaust and everything back on the SE.,. well anyways.. before when i just started it it up it had a smooth idle and it stay right where it was supposed to be.. but now the idle is at like 600 and the engine feels like it has no power,.. (usually backing into my driveway i can squeel the tires if i stomp it,.. but it didnt do anything this time)

if anyone has any suggestions of what i could check or if its probably just the timing or what, please let me know!

Sp it started doing this as soon as you put the exhaust back on?

yeah i guess.. i mean i never drove the car without the exhaust on so i dont know how "powerful" it felt then, but it seemed to be idling fine

but on a side note.. i hate my SE now and i'm completely fed up with it.. after all that time, work, and money.. i just took it for a drive to put some gas in her and guess what, by the time i made it back the temp. gauge was all the way up and there was a hissing noise coming from the back of the engine somewhere.. i suspect its where the heater hoses connect to the back of the intake manifold

either way.. i doubt i'm going to be waisting much more time on this POS

(if you cant tell i'm frustrated as hell right now! :evil: )

Check all the easy stuff first - Timing, TPS voltage, MAF voltage, o2 voltage, make sure you don't have any vacuum leaks, etc. Try running the diagnostic on your ECU as well. The hissing noise and overheating is definitely a leak somewhere. That sucks, but can be fixed cheaply. It just takes time. I know it's frustrating, but keep your composure and have lots and LOTS of patience. You'll get it going.

Take it easy, man, we'll get it running. I looked around last night for that old radiator cap from my SE that I mentioned to you, but I couldn't find it. If your overflow tank is filling all the way up I'd definitely say put a new radiator cap up there. As you know, if it's allowing too much pressure to build up in the cooling system, it could cause a leak like you're experiencing.
Give me a call if you're going to work on it this weekend, although it seems like it might rain most of the weekend. Just can't catch a break, can we?
Seriously though, don't sweat it, we'll get it figured out in plenty of time to go to the mountains and tackle the curves next month.
And we'll forgive your blasphemy of calling an S12 a POS. :no: ;)

Check all the easy stuff first - Timing, TPS voltage, MAF voltage, o2 voltage, make sure you don't have any vacuum leaks, etc. Try running the diagnostic on your ECU as well.
easy you say?! haha,.. well i checked the vacuum lines.. good to go on those

can you give me some advice on how to check the voltages? like where i would check them at or what..

Chris is going to help me with the timing and ecu so hopefully we can get it figured out

Thanks!

LOL By easy, I mean that you don't have to take your motor apart. ;) Well, you kinda need a service manual to check voltages. I don't have mine in front of me, so I won't be much help. But you need to know the right pins at the ECU to test, as well as the harness. Maybe Chris has a service manual?

I had an odd problem with an olds I owned about 6 years ago. Every time I stomped the gas I blew coolant out the radiator cap, but only when I stomped on it. The car was not running hot at all so this had me baffled.

Turns out I had a bad head gasket and it was not allowing coolant into the cylinder, but was letting cylinder pressure into the cooling system and then forcing coolant out the cap when it was over powered by the cylinder pressure.

You could be having something similar going on there. I'm not saying that you do for sure, just don't rule it out.

well i wouldnt hope that it'd be something like that since i just replaced the head gaskets and cleaned out all the crud that i could out of the coolant passages..

today i'm going to fix the hoses i know are leaking and hope that it might fix it,.. b/c it could be that since the hose was leaking that it allowed enough coolant to run out that it got hot.. im really hoping that thats what it was, b/c that should be an easy fix

Well if you are getting air into the system it will cause the car to start to overheat. So sounds like you may have found the problem.

maybe not.. i just found out why it was leaking in the back.. stupid me forgot to put the hose clamp back on :x

anyways i just filled it back up and took it for a drive around the neighborhood and guess what.. still overheating.. when i parked the car at my house i could hear the water boiling in the overflow tank,.. DAMNIT!!!!

i'm almost out of ideas....

I just did my timing belt and OI replaced the thermostat and put water wetter in at the same time. That brought my temp down conciderably.

I have a new radiator and electric fans and I was still running hot. (dead center without my air on) Now I can run the air and it will only get a smidge about center wich is a lot better than before.

I used a 170 F thermostat along with the water wetter.

For those not firmilliar it is a Redline Oil product.

ok.. well i went and got a new radiator cap today, and filled it up with 50/50 coolant and put water wetter in it... and it still got just as hot as before.. but this time it did take a little bit longer to get that hot

How long has it been since you changed the thermostat?

Also what is the condition of the fins in the radiator?

just put a new thermostat in like a month ago when i had gotten the new waterpump too

here is a pic of the radiator, the only place some fins are bent is right there in the middle.. and its just a little bit too, so i dont see how that could be enough to make it get that hot

Looks 1000 times better than mine did. My fins were so rotted all accross the bottom it wasn't even funny. They had fallen out over about 1/4 of the radiator by the time I got it to the radiator shop and when I had it in the hefty bags the fins were just crunching when I was holding it .

You may just have a large air bubble in the system. Have you tried topping off the radiator while the car is running with the heater on? Let the car run with the heater on for a few minutes while you continue to fill it. Any air bubbles should come out. If that doesn't work, then I'm not sure where to look from there. I'm kinda in the same boat still, except my car never actually overheats. It just always runs way up in the temp range.

Yeah Spooled is right about how to get the air out of the system. Not sure why those VGs like to get so hot when they get old. Very strange.

alright well yesterday Chris came over to help me out, he helped me check the timing and ECU codes, and the only real code the ecu was giving us was for the Cylinder head temperature sensor dont know if that could have anything to do with the car getting so hot,.. but what i'm going to do next is go ahead and get dual electric fans and see if those dont make the situation a little bit better..

Were the VG's treated to a larger rad over the other models, if not, over time it could at least partially explain the running hot...and dual electric fans should help...8)

The Cylinder Head Temp Sensor would not cause you to run hot. However, it would cause other problems, such as, bad idle, loss of power, running rich, etc. Replace that sensor. As for heating up, dual electric fans aren't going to do anything for you. If the stock fan isn't doing it, there's a problem, and you need to find the root. Are you sure your thermostat is opening?

well it seemed like the clutch fan isnt working properly anymore (and the stock electric fan has never worked as long as i had the car, so i just removed it).. so i'm just going to scrap it and see if the electric fans will do anything,.. i'm almost positive the thermostat is opening.. b/c i had bought it new when i replaced the waterpump, so then after it was still heating up i took it out and put it in a pot of water and it opened up.. so i dont know.. and i'll be honest,, right now i'm not really in the mood to take it out again.. so if the electric fans wont do anything then i'll take the thermostat out again

LOL I don't blame you for not wanting to take out the thermostat again, and if it opened in the pot of water, then it is probably working fine. If your fan clutch doesn't work then that would be a problem, but it should still take awhile for your car to heat up to the point of boiling over. I still say to check for air. It's easy to do and costs no money. :cool:

Seeing as you are still running the clutch fan, do you still have the shroud on the car?

I'll go ahead and answer that, the shroud is currently off, it hasn't yet gone back on since the headgasket job. So yeah the clutch fan isn't going to work right without it. But once the engine got hot yesterday (it didn't get to boiling, about 2/3 on the gauge when we shut it down, and it did take awhile for it to get there), so the fan should have been engaged, it looked to me like it wasn't spinning fast enough, just loping along like it does when the clutch is disengaged, I put my hand right in front of it and it was hardly moving any air. But I know the fan clutch wasn't totally disengaged because when I was checking the timing the cord from the timing light brushed up against the fan, and the fan was definitely being driven.
Back when I had my cooling system overhauled a couple summers ago, they figured out that the fan clutch was slipping, and, although it was OK when the car was sitting still, when you got going down the road the wind resistance would actually hold the fan nearly still. I'm not talking highway speeds, but city speeds where you would still need the fan to help cooling. So something similar may be happening here. In my case, dual electric fans helped a lot, even though my radiator is weak. I did the whole setup for about 70 bucks, and that's with multi-speed Stanza fans and dual independent control circuits.

alright.. just an update.. the SE blew a coolant hose (the little one that connects the lower and upper intake manifolds,.. its located on the passenger side.. you can see it if you look right below what the pcv valve is)

EDIT:well i'm just gonna give in and take the upper intake mani off again tomorrow.. i've already got it unbolted.. just didnt wanna have to take all the hoses and wires off again but i'll speed up the process, i'll keep you guys posted

ok.. but i did just get dual speed electric fans on a '88 Maxima,.. i've got them wired up and ready to go, so once i replace the hose, if i still have overheating problems with these babies then i guess its time for a new radiator

check out this thread if you wanna see my setup of how i control the fans,.. http://www.club-s12.org/board/showthread.php?t=6865. i'll post a diagram of the wiring tomorrow or whenever i get a chance

here is a pic of the fans, in the car,.. only took a little modification to use them (i.e. i had to cut notches for the hoses, drain plug, and sensor,.. thats it, .. was pretty easy actually.. just took a few minutes with a metal cutting wheel on a power drill!)

:disgust: I'm jealous...i want electric fans! looks good man!

I removed that coolant hose and blocked that port on my car. It's part of the throttle body coolant path. I just removed everything in that path.

ok.. well i just got done replacing the hose and it doesnt seem to be leaking, so i guess i did another good job *pats self on back*

anyways.. i'm about to head down to the muffler shop to have them reattach my muffler and then hopefully i'll find out if the fans do the trick or not.. WISH ME LUCK!

Good luck

alright.. got an update for you guys.. the fans worked awesome just like they were supposed to,.. BUT the car is still getting hot, the fans (in high mode) kept the temp gauge from getting above the break line, but it went right up to it.. when i got back to my house i finally figured out that there has to be a block in the radiator somewhere b/c the fins were cool to the touch, the upper tank was so hot that i could barely even touch it and the bottom tank was hot too, but i could touch it and keep my fingers on it for a few seconds

and i remember the guy at midas telling me that one way to tell if the radiator is blocked is to see if there is a 30º temperature difference between the top and bottom tanks.. and i'm fairly certain there is!

Outside appearence of a radiator can be decieving. It can look great on the outside but can be bad on the inside. I have delt with this type of problem before. Same kinda symptoms only it was on a Volvo. A way I learned you can test it in the car is to first remove both the upper and lower hoses. Then pour a gallon of water quickly into the radiator (thru the upper hose inlet is best) then see how fast it (the whole gallon) flows thru. It should flow thru VERY QUICKLY! If it does not then you know that there is too much restriction/blockage in there. Remember a little build up throughout the entire inside surfaces can cause a fair amount of flow restriction and heat transfer problems. This was the case with the Volvo I mentioned earlier. I replaced the radiator and everything went back to normal.

Another thing it could be (although this is very rare) is that the impeller in your waterpump has slipped off or is spinning freely on the shaft. I never thought about this until I saw it happen to a friend of mines car. It was bizzare!!

Hope this helps...

200SXSEV6

yeah.. i'm thinking thats what it is.. i'm getting another radiator from Ryan (200sxSE) and so hopefully that'll take care of it,.. i really would hope it isnt the waterpump since i just bought that brand new last month

..worries me that you hope..did you not check it to ensure it spun normally? (by normally i mean with very little drag, but there should be some)..did you try drano? maybe i should be hit for saying that..but would it work? Im not sure of the cehmical reaction that may come about..but could it be worth a try?!

and..200SXSEV6 Welcome to the club!!