Cooling system - new : Still heats to around 250*, resevoir gurgling/bubbling and very hot to touch.

@#%#$ SES light, it's about to get some black tape across it.

Possible culprit and/or hint to my problem - code 33: Bad or faulty ECM or MAF.

All new sensors, except MAF, MAP & fan relay. Fan kicks on at the same point of temperature everytime.

full new exhaust system.


I've spent around $600 trying to get my temperature down in the car, and nothing.

I'm | | <--- this close from gutting the car, putting it in my garage, and rebuilting it over a year... and buying a honda (shudder)

I need some help. Some serious help. 3 Mechanics, and they can't pinpoint jack squat. I'm peeing my cash away here, so whatever help you ALL have, it's definately appreciated.

1989 IROC V8 5.7lt TPI.

Whatever you all need to help me, I'll get it. And thaaaaank you in advance. (I'm also gonna follow Willie's cooling guild btw)

 

my friend looked into getting a GTA with the same problem. is the coolant circulating and ifnot its the water pump. my car had an overheating problem also i ended up putting in a new thermo, fan motor, fan switch, and intake manifold gasket. not overheating now but just a few things u might look at. im no expert by a far stretch but wanted to comment on a few experiences i had that might help you out.

 

Kevs,.. it helps like you wouldn't believe.
The pump is working, opening the radiator cap you can see the fluid getting pushed in a circular manner, and the pump is not making a horrendous noise like I stabbed it

Lo and behold, my air dam is freaking missing. I understand my engine is not getting the air it needs to cool off while driving, but also I tested it with the car sitting in my driveway running, checked the temp. , same problem.

My car....honestly, hates me or doesn't trust men anymore since the last one mistreated it.
Sounds like a woman. :/ She's b**chy, pains me when I'm trying to help her, and doesn't appreciate anything. thank the *** upstairs my woman is not like this car. hehe.

1 thing about the fan and the sensor is that the fan kicks on at 245-250*ish everytime. Could the fan motor/sensor be dying if it's kicking on at the wrong time?

Oh, and could the ECM/MAF be the cause of the problem!

 

the maf sensor could be sending the wrong signal to the ecm, making the car run lean. Next time you run the car, unplug the maf sensor, you'll get a code, but the ecm will use a fixed value for the maf sensor reading. If it runs better, then the maf is the culprit.

 

i didnt even see the thing about the MAF sensor


did you take the screens out recently? or change the intake in some way? missing air dam isnt exactly something i would drive my car around with. without it i have heard there isnt a lot of airflow causing the maf sensor to go bonkers and throw a code and send the wrong signals. missing air damn could also cause the maf sensor to experience more wear and might have died. get an air dam and see if it helps. if not then change the MAf sensor. its like 180 i think at autozone. bring in the old one so u dont have to pay the 80 core. like i said im not an expert and if things i suggest dont fix it im sorry you wasted your money on parts. it a hard problem to diagnose but since your fan is kicking on and it is circulating check the MAF and get an air dam and possible check the coolant temp sensor maybe it isnt working right.

 

Seems as if the primary fan is not turning on.

IIRC, primary should come on at 235, off at 220...2ndry fan on at 242?? Something big like that.

Turn the AC on, both fans should come on.

If only one (I'm guessing) means you have a problem with the fan.

On my '89, the driverside is the primary, pass side is the 2ndry.

Just a start.

 

he said the fans are working tho.

 

Cool beans. I was gonna test it, but Autozone was outta testers. Blah. I might as well rip that sucker out and see if it does run better, if it does, I'm definately throwing you guys a party at my place, BBQ, girls, and booze.

Yeah, the Air Dam is a definate. I was shocked to see it was missing.

I might replace the relays and the MAF sensor together.. might as well get it done. And no worries on replacing the parts, sooner than later I'll have a new car, and it's helping pinpoint the problems.

 

Just try the relays 1st...and then reset the ECM...

That should help.

 

8Mike9, the primary fan is working correctly, the 2ndary fan isn't comming on, unless I turn the AC on. My guess I should go ahead and replace the fan relays, and MAF if it tests bad. Other than that, I have no idea. The car is not burning oil at all. This beast of a car is scaring me. Soon it's going to start asking for sacrifices to keep it running.


I'm doing that first thing tomorrow.

 

second fan wont even come on until way late in the game. it isnt going to keep the car cool. its something else. im betting not having the air dam killed the maf

 

"1 thing about the fan and the sensor is that the fan kicks on at 245-250*ish everytime. Could the fan motor/sensor be dying if it's kicking on at the wrong time? "

This implies (to me) that only one fan is working...based on the temp he's reported, it would be the 2ndry fan.

89rocs...which fan is coming on...or are both fans coming on?

 

my secondary fan doesnt come on till way late if at all. it doesnt influence keeping the car at a normal operating temp. it is mostly to help out with the strain of traffic and the ac. i have always been under the impression that it was only going to come on under a high stress situation where one fan was not enough

 

Okay, here we go:


the primary fan is engaging.. (left one) at temps of 240-250ish.

the secondary fan seems to kick on when the AC is on. The last time I seen it work was at the mechanics shop. The right side kicked on, and the left didn't. Now it's working the other way around.

 

I don't think the relay(s) are the issue.

Your problem is the primary is coming on way too late, based on your reported temps.

ECM get's input from the CTS (front of intake manifold). ECM then sends signal...based on temp reading, to the primary fan relay to ground it and turn it on.

My guess would be CTS is reporting inaccurate info.

Do you have access to a scan tool to plug into the ALDL and monitor CTS reading vs. gauge reading?

 

just take the ses light out LOL.

 

Unfortunately no I do not.
So, it is possible the ECM is working properly, but inaccurately due to the CTS reporting wrong? Hm..
So many possibilities. After I straighten those out... I gotta figure out why my car "drags" after I hit 1500 RPMS and then release the gas. It will drag to 1000 RPMS, and releases. I can feel it everytime.


PITA car.


LOL Icebird. Or I'm gonna use some black electrical tape.

 

"since your fan is kicking on and it is circulating check the MAF and get an air dam and possible check the coolant temp sensor maybe it isnt working right"


already mentiond the CTS. that would be the cheapest thing to replace maybe it got disconnected. why was it at the mechanics?

 

Hmmn...the boggling of minds

Try this.

Jumper A and B on the ALDL, turn the key on to run...don't start the car.

Both fans should run.

 

what do u mean by drags? is it acting like its under load like its pulling a MAC truck?

 

The car went to the mechanics because my car started to overheat. I burst the top radiator hose, and oil was leaking into the radiator. I had gotten the radiator, O2 sensor, stat, and 2 other sensors replaced.

I'm getting tempted to go out in the rain and look to see if any connections are loose or disconnected.

Ah, jumped it earlier yesterday. Primary fan was the one that engaged, the other didn't move.



Kev, Exactly!

 

I was talking about replacing the MAF relays to fix the Code 33...

As for the what temp the fan is coming on at, are you using the stock temp guage to compare against? It is notoriously inaccurate...

Can you hookup some diagnostic software to the ECM and verify what the coolant temp sensor is reading (at the ECM)??

Otherwise you don't know for sure what the temp is...

 

88TPI -

I could head out tomorrow and have it tested at a shop.


Yep, I'm going against the stock temp gauge, but I'm not 100% positive on if it's close, but the overflow is boiling, and burning to the touch.

 

lol..I agree, tape is easier than getting the bulb out.

Before spending any more money, everything electrical in the system can be tested with a DMM/DVM. I know Vader has posted the CTS ohms vs. Temp several times. It's also in the Chilton and Haynes manuals...directly reprinted from the Helms.

My guess is it's posted on the cooling board as well.

 

check the connection on the CTS if the o2 was replaced and the thermo then th guy might have diconnected it and forgot to re connect it. mine was on the driver side between the first two plugs.


changed the tranny fluid lately? checked the adjustment on the rear brakes? u dont have the e brake on do u? lol

 

Well, for all this effort and knowledge shot my way, I'll grab a tester and do some vader searches on testing, and replace the relays. No biggie there.

Kev, a salute to you. Hehe.

No, no ebrake on, rear brakes were done a month and a half ago, and the tranny fluid is perfect.

I still don't understand why the ..... my car seems like it runs under a load at 1500 RPMS to 1000 RPMS the releases. That started when my car overheated.

Btw, Kevs, 88TPI, 9Mike9... if you guys need any Suburban parts, lemme know. I have one about to be pulled apart soon.

 

has the fan switch been replaced yet? becuz maybe thats goin and it only working in the upper temps. u should try a hypertek fan switch. my brother has one on his 86 sport coupe and it works great.

 

Timz2882 -

I'm gonna head that route as soon as Willie emails me back with the specs to re-wire my car. Gonna put a 179* stat in, along with a switch to kick the primary fan on around 185, and the secondary around 200. Willie has a VERY nice write-up under the cooling section posted by ede or breathment. Check it out.

 

I read wher you mentioned "oil in the radiator"...could be tranny fluid...could be related to the "drag" you mention. Check the fluid level, smell it and make sure it's not burnt.

Before you modify the fan wiring, best to make sure everything works normally/correctly first.

Tell Willie to send you a pic of his "cockpit" too...looks like he's driving an airplane.

 

ur maf sensor plugged in? i have forgotten to plug mine in a thousand times. it must feel like its under load because this problem. its straining the engine because the water pump is trying to work harder to compensate or something like that. after you fix this if it doesnt go away i will be shocked. my car has an odd problem where it acts like the brakes are on in the back all the time. i havent changed the back brakes and might look into it tomorrow since i dont have school anymore and have nothing better to do.

 

doesnt the tranny fluid run through the radiator too? maybe when the air dam got ripped off it busted the radiator up and no the two are mixing together. not good for the tranny if so.

 

Your kidding me, it looks like a cockpit? Heh, I'm gonna have to see that one myself.

The transmission fluid is right at the hot level after letting it run for 5 minutes, and it's still that pinkish red color.

things to do tomorrow:

Replace relays .. check
check MAF sensor.. check
elbow drop the car...check
check the ECM...check
check the CTS? check.

I've peered someplace on the messageboard that a broken forward sprag in the tranny could also cause the car to act like this? The guy ran his car for a year before having to finally replace the tranny.

Blah.

the garage and the car are so close to being best friends right now.


Kev - I replaced the radiator yesterday

I'm about to jump in the chatroom in a sec here, since I'm trolling this post hehe.

 

where u mentioning the guy replacing the tranny in reference to the drag or to the overheating? the cts is coolant tempature sensor if u wondered what CTS ment. it has a single wire going to it. if u have manifolds on the car and not headers then put your thumb on the one closest to the front of the car on the drivers side and follow down. it will be pretty close to that. if u want a pic i can run out and snap on for ya.

 

I should slap my head for that one on the CTS --->


It's one of the sensors that was replaced. Nothing was done to the tranny at all.

There are no breaks in the new radiator, and there is plenty of pressure forcing it.


I hope to *** it's the ECM, MAF, or relays.

I'll have pictures in 2 weeks if not of my iroc dismantled.

 

i wouldnt be hoping it is anything but an unplugged sensor or a bad ground lol the ecm and maf arent exactly a cheap part but if u got THAT much money find me some door panels and an iroc dash emblem lol

 

If it turns out to be anything like what you mentioned, I'll mail you the emblem, and possible panels.


You do know, if I had dismantled the car and it was an unplugged sensor, I'd definately have stopped using this name and made another lol

 

well i hope it turns out to be something i mentioned then haha im kinda feeling better about my car knowledge now cause i guess i know more than i thought. still not the smartest person on these boards. in my opinon Vader claims that title. i stumped him the other day tho so no one on here is the big king or anything. probably why we have this site. everyone puts there 2 cents in and we figure things out. glad to feel like i belong somewhere for once. i need that emblem BAD i might be buying door panels saturday night if this guy turns out to have them in decent shape. wondering about the carpet tho. do u have yahoo messenger or aol? if u have it and want a faster response then on yahoo im kevin_iroc87 and aol im aekr17

 

Vader, Willie, Ede, Breathment, and Kevin know a boatload, but it's everyone on this board helping everyone out that makes a difference. It's hard to know everything.

I know minor things, nothing like boring, rebuilding trannys, or even have the tools to do the job. It sucks living in a slow state, just no real jobs paying squat around, hence the poorness my car is making me

I'm checking on the emblem right now, and yeah I got AIM.. I think. I'll add you


Btw, I'll keep everyone updated about what happens when what parts get replaced too

 

Okay, I replaced the MAF relays and disconnected the MAF sensor.. the car runs worse with the sensor detached, so I'm guessing the sensor is working properly.

Well, I think I narrowed the problems down to 2 things...

Air Dam causing the car to stay too hot while it's on the road.. it's missing
Transmission is starting to go on my car, hence the under load feel it gets when hitting 1500 RPMS then releasing the gas.. til 1000 RPMS then it seems to release.

Other than that, I'll use Willie's guide and help the car cool.

 

Good news! My tranny is fine, I replaced the MAF relays... and a fan relay. It's NOT the tranny. The car runs like a kid chasing an ice cream truck. Still heating pretty bad... and I noticed 1 thing. sediment in the fluid after getting the radiator and hoses replaced. They didn't freaking flush it. So, I'm going to flush the radiator and block til i get the crap out, replace my stat with a 170* stat, and follow the Willie guide ...oh, and replace my air dam. Just FYI if your car is running the same.

 

hey does this mean it was something i mentioned? am i getting door panels? please oh please oh please say yes lol

 

lol sup Kevs

Guess what... after taking it for a lil test drive, then parking it, then hitting the little store... the car is now doing it AGAIN>? (running like it's under a load @ 3rd gear @ 1500 RPMS thjen releasing at 1000 RPMS...

I did make 1 boo boo. I didn't disconnect the battery and let everything reset. Think that could be the cause of it defaulting back to the odd "under load" feeling?

 

if i were you i would disconnect the batter cable and unplug the MAF and wait like a half hour just to be sure. even tho it only takes a few minutes for the computer to reset i always disconnect it and do some cleaning in the bay or sweep out the leaves and grass from the floor mats. it just gives enough time so you dont wonder if u had it off long enough. just a suggestion. leave the cable off until the feeling that maybe it hasnt been off long enough goes away. maybe your rear fluid needs replaced. my car acts funny if im off the gas going down a hill. it acts like im braking when im not and i think my back brakes need replaced. ever polished a plenum? if u have email me the process or tips.

 

My 92 6cyl was running hot a little while back, I went thru everything replacing hoses and such. Turns out I had run over a curb which put a dent into the bracing holding up the radiator and fan. Well the fan was jarred enough so as not to turn on. Then Radiator had a dent into it also.
I fixed these things and ir ran like new.
I know this dosent help but....
(ah whom I kidding I just wanted to sound important)
see ya

Craig

 

well, i tested some more today. The fans do kick on, the secondary works when the AC is on. Plus the Radiator was replaced, so it would be on secure. One thing I didn't get to do was to flush the radiator... was too busy pulling up flooring to make time for it. :/

 

Radiator is kinda a B*tch to get to and work on isnt it

 

i would flush your radiator asap if it has stuff in it. mine has little bits of metal in it but i dont want to flush mine. too lazy plus nowhere to put the antifreeze. check out the MAF yet?

 

I'm gonna flush it tomorrow.. because this temp problem AND "drag" is really, REALLY peeing me off. After flushing the radiator and block, if it STILL overheats, I'm replacing the stat, all wiring for the fans, and >hopefully not the MAF< MAF. 1 question though, I noticed a moderator posted that disconnecting the MAF is a way to test it. If the car runs worse after disconnecting the MAF sensor, then the sensor is fine?

I did so, and it ran like crap til reconnecting the MAF.

 

this overheating problem is very confusing for tons of people because it can practically be anything. i would find another cheap maf sensor from like a junkyard and see if it is any diff. not too sure if a junkyard has the maf since people who own our cars know to part them out. worse case scenerio you replace it then know its good for a while lol


running out of suggestions. what stat u have in?

 

I had a lower radiator hose that was collapsing at about 2000 rpm and it was a pain to find. I replaced radiator, water pump, and thermostat. Come to find out it was a $15 hose. The hose wasn't even ruined, just the spring in it wasn't positioned right. At an idle everthing seemed right and it was just luck that one day I revved it up a little bit and seen the hose collapse.