weird overheating issue - b18c - help diagnosing

ASSISTANCE Hybrids & Advanced Aftermarket Engine Performance
1

hello all!

so, ive got an issue here. a few weeks back im driving through the village of Pittsford when she decided she wanted to overheat. shit. little stop and go, warm day, but nothing out of the ordinary. i get to some open road, and she cools down…this is where it gets odd.

i get home and start testing things out - oddly, she doesnt overheat while at a standstill in my driveway. at a standstill she runs perfect, fan turns on and the temp display is smack dead center. while running however the heat can shoot from comfy at mid way to full on overheating in seconds. letting it run for about 3-4 cycles of the coolant fan.

so about a week ago i pulled the thermostat. ran it like that for a 3-4 days and it ran like a peach. (idled at 4k though) almost never reaching operating temp and never overheating. awesome i says. i go buy a new, stock thermostat, take everything out (i had to remove the starter each time…anyone else have to do that? what a pain :slight_smile: ). i get the new thermostat in, test it at idle for 20-25 min, works great. take it for a spirited 20-25 min drive around the country, alls well! runs mint, idles at around 2100 or 1900, which is the best it ever has TBH.

then yesterday, on my way back from napa, wind in my hair, windows down, sunroof open and a new spark plug on the passenger seat ( for the riding lawn mower) i cautiously look down and im overheating!!! WTeeeF?!?! i turn off the car and coast to the side of the road immediately. pop open the hood and, what the effing eff, the coolant reservoir is almost overflowing (i topped it off 2 days ago as it was as the MIN line, i brought it up to the MAX line) i also believe i ‘burped’ it properly when i replaced the thermostat, but this being my first time and all im not sure.

so, i emptied it to the max line, drove home (i was less than 2 min down the road at this point) and shes been sitting there since. i did have to start it, let it run for at least 20 min and turn it off a few times as i was trying to diagnose the riding lawn mower and i needed a battery, and well, she didn’t overheat then.

when i popped the hood yesterday on the side of the road the voice in my head said ‘theres gotta be a blockage in the cooling system’.

anyone have anymore intelligent voices in their heads? lol or rather, more informed voices? im just getting back into the scene after about 5 years without my integra, so im …rusty. lol

TIA for any and all help. this is my only vehicle at the moment as my CR-V has seized its brakes :slight_smile: so, i need to get er going!

~TrecePulgadas or as im know everywhere else; Joseph :bow:

TLDR: car overheats while moving. replaced thermostat. ran fine for days, now doing the same thing. does not overheat while at a standstill. believe car was burped properly, not sure. :ohyeah:

2

Hmm, you were definitely on track with the thermostat idea, so strange that it’s happening still. Assuming there are no leaks and it’s burped properly then I’d try a new radiator cap since it’s so cheap and easy. It could be releasing pressure too early.

But the big :think: for me is why the hell your car is idling so high. 4k idle!!! Then down to a 2k rpm idle? There’s something wrong with that and should be looked into. Hard to say for sure whether these two problems are related at all or completely independent.

3

ok cool - im headed out in a few ill stop and grab one. until recently i honesty didn’t know it was more than just a ‘cap’!

as for the idle, it has always idled high, for sure. i don’t know if i specified; it was with the thermostat removed (no thermostat) that it was constantly idling at 4K. before the new thermostat it would idle at roughly, oh id say closer to 2500. now, with the new thermostat IN, on start up it revs to about 3500 then as the engine warms up it settles down to around 1900-2100.

i [i]think[/i], again im just guessing, the biggest issue is the fact that i do not have the correct ECU in it…the guy who had it before me removed it to use in his Chump Car and replaced it with, what i think, it a Civic ECU. i had a photo of it somewhere, ill see if i can find it.

it also has Skunk 2 Stange 2 cams, high comp valves, lightened flywheel etc etc…will this cause a higher than normal idle?

thanks again !:auto:

~joseph

4

The idle issues combined with the overheat and especially the really quick overheat lead to me think you have air in the system. Air in the IACV will cause erratic idle.

5

That’s what I was thinking too. In my experience this has been, just as you say - erratic, but seems like he’s experiencing a consistently high idle. Perhaps it could cause that as well, but I haven’t experienced it. For me it’s always been “bouncy” when there’s air in the cooling system.

13pulgadas: can you clarify what’s going on with the idle? After your last post, I personally wouldn’t be driving this car for fear of slowly doing damage to the engine. I’d get the right ecu, try to get the idle sorted out as best as possible, fix the overheating and get it to a dyno tuner ASAP. If you can’t afford a tune then I’d ditch those cams and run a stock engine with a stock ecu.

6

well ill be.

ive got it now parked in front of me on a hill that my house sits on. why i didnt think to park it here before, i dont know. :hmm:

parked it, let it cool, took off the radiator cap and within, id say 60 seconds, she started burping all over again. it lasted intermittently for about 5 min; its been running around 15 now. temp is cool at mid range. fans kick on. level in the reservoir is still good. i took a quick video and managed to capture the burping and the hill shes on - as soon as it uploads ill post a link.

so i guess ill sit here for a few more mins and make sure it is done.

as for the idle - i watched very closely today, and have video too:

on start up it goes to 3K, hunts to 3100 and then steadily drops and settles at 2250.

im guessing that the times that ive had issues in the past were D/T the air bubbles in the system.

still here going on almost 20 min. purring like a kitten.

assuming the idle/overheating issue is solved with the burping it should be fine to dry now yea??

where do i start with getting a new ECU? i think this is one of the reasons, the other being $, as to why ive never attempted, im noteven sure where to start? the ECU i currently have is 37820-p06-a50 - which i believe is to a 92 civic. :shy:

thanks again ! :rockon:

EDIT: idle just dropped an octave! now we are sitting at just above 2K - will wait a few more and report back
E2: and we keep dropping. 1900 now. this is great.
E3: so after a total of 40 min the idle stayed constant at 1900; ever after moving it off the hill and into the driveway the idle was consistent. i brought the wife over, who bought it she said shes never heard it idle this low. even when i picked it up at his garage it idled high. so pumped.

7

Pull the cover off that P06 and see if it’s socketed and chipped. I’m thinking it must be as that is a stock non-vtec D15 ecu and your B18c w/ cams would run like dog shit on the stock tune. Glad to hear you got the idle and hopefully overheating figured out.

8

ok - i will do that - im guessing i will be able to tell its chipped? ive got no idea what im looking at.

as for how it runs; pretty good really; not great. def not perfect. at high RPM she dumps way too much fuel. coming out of vtec causes some significant bogging, or sputtering. feels like the mixture is off. i also cant get on it too much in certain gears at certain revs because i can feel it dump way too much gas. A/F runs nicely around 15; its an analog gauge so thats the best i get really lol

gonna head in from the backyard now and check the ECU - we got baby ducks a while ago, i could hold em in my hand (and ive got very tiny man hands) - now, less than 2 months later, they are full grown, feathers and swimming in the murky pond we dug em. ducks are cool man.

ECU!

9

so - i believe that it is chipped. there are 2 chips that seem a bit big-ish on it.

here is a photo

https://photos.google.com/share/AF1QipOW-K1DlzU5j-sp2TnKFj_021PQQn-FmFgla9Pm3fpy_kaZZEWY3atw9mN6zrGWSQ/photo/AF1QipMYYkDzDZAz0pNOZCTfCIi0nLyBG3O5FF2scvJ7?key=aHBLQ1JwWjNZVWRGQTVGS2p4SVRrVjBxSzNReXJn

another photo

https://goo.gl/photos/c98nMWhBgfsmpbyv5

heres the video - turn the volume down - 'tis loud.

https://goo.gl/photos/Gcc3oMcPkNP9ApaP8

10

Well fellas, I’m pulled over on the side of the highway. Not good.

I’m about 25 min from my house, needle was in the red. Pulled over, popped the hood, check the reservoir and it seems to be bubbling. No boiling, but air bubbles.

What gives? Gonna wait till it cools, drive it back home and take the CRV on the 2 hour drive today.

I posted the video, did I do something wrong or not enough?

There is fluid in the reservoir and as of last night there was plenty in the radiator.

Thanks !

11

Have you ever bled it with the bleeder screw on the T-stat housing? Cycled the heater to bleed the heater core? Air bubbling in coolant sounds like it could be a headgasket.

12

I haven’t done either of the things you mentioned; I’ll give it a go tomorrow morning before work, provided it wont take too long. Is it a straight forward process?

Any other symptoms I could look for if it were head gasket related? I haven’t seen any smoke nor smelt any of any color from the exhaust.

Thanks again!

13

blown HG usually mixes oil and coolant somewhere. Coolant doesn’t look milky so check the oil.

14

first things first, figure out what the car is tuned on… secondly i would stop driving it if it has big ass cams and head work on a stock ecu. you are definitely on the verge of melting some pistons or popping some rods out of your block…

as for the over heating try this…

remove cap, open drain plug on bottom of radiator and flush every last bit of old coolant out
replace drain plug…
fill with proper mix of coolant and distilled water, please do not use hose water.
once topped of start the car and let it idle with the cap still off, also be sure to turn the heater on as well…
wait for the fans to cycle, top off any coolant you are low and then place cap back on the car while it is still running…

if you are still getting over heating issues after this you need to start looking at headgasket or water pump…

15

Forgot to mention earlier that yes your ecu is chipped so it is not running on the stock D15 tune (obviously since vtec is working) However it sounds like it really needs a new tune.

16

alright! i will go ahead and get the coolant this week when i go to get all the parts for the CRV. ill give it a complete flush as slow_db2 described, give it a test ride and report back.

as for the ECU, im guessing it is something i am going to have to take to a shop? its not something that i can tackle on my own is it?

TIA

:dance:

17

Yeah find a reputable tuner in your area.

18

ok - CR-V is mostly fixed and on the road.

i did not flush the coolant in the integra. i pulled it up on the hill, about 2X as high as last time, turned the heater on full blast and let her run for about 1/2 hour. there were bubbles…and plenty of them. i capped it shut after i did not see any bubbles for roughly 4-5 min. after it bhad been running 1/2 hour, while staying at the proper temp, i took it for a 20 min drive, at first 10 min at speeds of 40-60 and last 10 min of speeds from 60-70mph. it stayed cool as a cucumber the whole time. i turned the heater off for most of the time as well to be sure it was fixed…hopefully.

ive checked all i can, aside from pullng the head, and as far as i can tell i have no other tell tale signs of blown head gasket - no milky oil, no oil in the coolant, nothing on the oil cap, no sweet smells of burning coolant while driving…so theres that.

ive got about a 1/2 hour drive into work today - leaving in about an hour - hopefully ill post that all went swimmingly well!

so is that the proper way to burp the system? elevate, remove rad cap, heat on full blast and let run for X min until bubbles stop? is this how its done in a shop?

so, do you guys recommend getting a new ECU and going from there or first seeing whats on this one? is it worth it to try to keep this on ?

Thanks again everyone - cant thank you all enough.

~Joseph

19

Keep your ecu. The chip is removable and reprogrammable.

20

little late response, but as far as the bleeding goes, as long as you can get the Radiator Cap, the highest elevated point of the coolant system, that is the proper way to bleed. LISLE makes a very very good coolant burping/bleeding funnel kit, can be found at most parts stores or had online for roughly $20, comes with a handful of adapters for a hand full of makes and models, even used on OEM and aftermarket Honda rads. Works extremely well, i found it out of the blue one day, but since i have started working for bmw, most if not all the guys in the shop actually prefer the same kit