Ok so I've been workin on gettin this car straight and driveable. Got it from a friend in running condition but was supposed to have overheating problems and water pump was bad. Changed pump, and stat and now I'm lookin at the cooling fan which appears to not be working properly. Fan works wired direct but I think the relay or switch is bad. Is there a way to test the relay or switch? I dont just wanna drop the money on the parts without knowing if they are bad Also, today when I was troubleshooting on it, I started it and let it run for about 15 minutes trying to get it to operating temp to see if fan would kick on. Fan never kicked on and it looked like it was about 210 on gauge because it didnt get to 220 mark. I tried turning on the A/C to get the fan to kick on but it wouldnt do it either. A/C compressor kept kicking on and off right away so I dont know if that was why the fan didnt come on or if the relay thats messed up. Also noticed a vacuum noise from behind the A/C panel so I'll probably have to open that up and find that leaking hose. Now while this was going on the oil pressure gauge was bumping back and forth from half way to full the whole time until it got warm and then suddenly the needle was on 0. I gave it a little gas and it would pop up a bit but not far, then come back down. Are these oil press gauges really worth a crap or is it messing with me? Seems to me the motor was runnin fine other than a little rough and with what sounds like an exhaust leak but thats all the time. The little needle bounces around alot even when its up at the top.

oil pressure sender is commonly bad on these cars, theyre located by the oil filter, you can see it if you lean over on the driver side and look down under the exhaust manifold.

does the fan turn by hand? the fan motor could be burnd out

i dont know where the relay is. maybe someone else can shed light

you could always rig a switch

I don't know if this will help, because I don't know if this is common with these cars, but the temp guage on my dash is way off. For a long time I couldn't figure out why my car was overheating and why the fan wasn't turing on correctly. Ended up it wasnt.

But, If someone could shed some light on how to plug up that switch that would be awsome. My car had one installed when I bought the car, but somewhere along the line a mechanic that was workin on it unhooked it, and I can't figure out where to plug it back up.

"I tried turning on the A/C to get the fan to kick on but it wouldnt do it either. A/C compressor kept kicking on and off right away so I dont know if that was why the fan didnt come on or if the relay thats messed up"

Probably low on refrigirant or something


"Also noticed a vacuum noise from behind the A/C panel so I'll probably have to open that up and find that leaking hose"

For me, it was that turning wheel thing on the A/C selector switch in the back....a bit of a pain to remove IMHO...but the part is cheap from a JY

Yea the A/C doesnt have refrigerant but I figured I could turn it on just to see if it would turn the fan on but like I said it wouldnt stay on.

I've seen the oil sending unit, big long thing stickin out over the filter. I figured it was workin ok before though since it was registering other than the jumpiness. It surprised me how it all of a sudden showed zero out of nowhere.

I know the fan is fine because I took it off and direct wired it to the battery and it came right on. Apparently theres a pressure switch in block and a fan relay which control its operation. I'm used to EEC-IV Fords where I know pretty much everything thats in there so this is all new to me. I dont trust these gauges at all myself. I'd like to have some aftermarket ones but I dont wanna goof out the interior on the slow beater car.

Funny thing on that vacuum leak sound, when I would turn it just a little bit from off it seemed to go away.

Same thing as my car! haha The compressor cycles on and off when it doesn't have enough refrigirant. Also, my switch did that exact thing with the vacuum noise. ouch it a little and it goes away. Annoying noise ain't it?

Havent had time or ability to properly test it. Idling for 15 minutes didnt get it up to the 220 mark on gauge. I would have left it longer but I was trying to be careful since the oil gauge was reading 0 all of a sudden. Other thing is I need to install an air deflector since its missing. Was going to buy that and several things from a guy on here but hes not responding back yet.

Already picked up a Haynes....I know they suck but its better than nothin. Not really any info on the fan in there though.

I'll have to check into that sender..how much they usually run?

I did put in my grid lights today though since I didnt do the other stuff I wanted to. I got in such a hurry I left off one of the rubber seals Gotta pull that side back off...had to goto work at 1:00-10:00 so ran out of time

Sender probably wont be terribly expensive.... I'd just replace it with a manual gauge mounted on the cowl and be done with it.....but thats just me. I wouldnt run it until you get something to verify that you ARE making oil pressure, otherwise kiss your motor goodbye. And yeah the fan is supposed to come on when the compressor kicks on in addition to the temperature so you prob got a bad relay there. Relay should be cheap, thats what I'd do

Buy an el cheapo oil pressure gauge from walmsrt (6$). it threads into the same place the sender does and will be able to verify what the sender is saying.

Is there any logical reason why it would show oil pressure for 15 minutes and then suddenly read nothing? Is that really mechanically possible. I figure the oil pump either works or doesnt, not in between. I'll have to start it again cold and see if it starts back up with pressure or if it stays at 0. I'd like to find a good spot in the interior to mount and oil pressure and water temp gauge since those are the two critical ones. Probably just run an electrical model to make things easier.

yeah theres a logical reason, the gauge is bad. Or something is. Every camaro Ive encountered never had an operating oil pressure gauge. Mine, for instance, moves around freely and if it could it'd do a complete 360 either way. My pressure is fine, just the gauge likes to freak out.

also learned the wiring on the cars arent the best. IF you think its a relay just pick a couple up from the junkyard and switch em. Theres just not a huge chance you'll end up with a bunch of bad ones.

When i got my 2.8 it was doing the same thing... good pressure, then would go to zero once warmed up. IT turned out to be the oil pump going bad...I was just saying, it is worth the 6 bucks to know for sure what your oil pressure is. IN my case, the mechanical gauge agreed with the stock one...

Yea I get ya, sounds like probably a good idea. Still dont understand how an oil pump can work cold and freeze up when warm. I've not had one go bad on me but my mechanic friend picked up a mustang once with an engine problem. We pulled cam and found it was siezed up so we sanded it smooth and put it back and the motor ran, but then we noticed there was no oil pressure. Got an oil pump for it and then we pulled the pan and found the oil pickup tube was completely blocked with oil gunk solid. Cleaned that out and everything was fine.

In this case its like...how can it be working then stop. I guess I dont know the mechanics of an oil pump. I will be looking to get a gauge here soon to try our theories. Thanks for the input.

I picked up the 6$ walmart gauge today. I havent tried it yet. Seems I may have more problems now. I tested my fan relay and found it works fine and grounded the green/white wire and fan came on so that means that if the fan switch works properly and grounds itself at right temp fan should work. I slapped in a new fan switch.

I put a little seafoam in the oil and started it up to try and let it warm up and watch the gauge again. Showed pressure for a little while and once car started warmin up some I saw it slowly fallin and then it went back to 0 and acted the same. I turned car off and started it again and then the needle popped back up to the top again.

Now the new problem is that I've got some ugly sounding clanking noise at front of the motor. It strikes me kind of like a bad pulley or bearing or something. Seemed like it was coming from waterpump/crank area. I pulled the belt and turned all the pulleys by hand that I could. Water pump seems to turn fine, as well as the rest except for the smog pump.

Smog pump seems to have a little play on its shaft and seems like maybe at speed it could be making the clanking but I'm not sure.

It wasnt making these noises before. I'm going to change the oil and filter tomorrow just in case that could be causing issues with oil pressure and the clanking noise. I hope it aint the bottom end clanking.

the air/smog pump should only run for a few seconds after initial startup. the clunking noise could be exhaust shield ratteling?

although running the car with 0 pressure is risky

I wasnt running the car on 0 oil pressure. The noise came on way before the gauge started getting funky. And like I mentioned, I turned it off and then turned it back on to see what gauge would do and it ended up going right back up to the top of gauge again.

I dont know all about how the smog pump functions but its always being turned by the belt and thats what I'm talking about. As if the shaft has too much play forward and backward and possibly causing a noise. I was able to make a little noise with it by hand because of this. Brackets and access all seemed to be tight when I fiddled with them except for smog pump.

One thing I could use help with is the aftermarket hookup for oil gauge. I saw two connections right by filter. I'm assuming its the top one but was unsure.

The larger one , that looks like a cylinder screwed into the block is the oil pressure sensor. It is the top one if I remember correctly... You want to unscrew that. One of the fittings provided with the gauge will screw right into that hole. The other gauge is an oil pressure switch for the fuel pump....

Thanks for the info as haynes gave me nothing. I was just under the car draining the oil and swapping filter and was looking up at the two pieces. I was like come on how am I supposed to know which one

Tomorrow I'll try and hook the gauge up and put in the new oil and hopefully see good things.

Ok, so changed oil and filter, installed walmart gauge. Clacking noise doesnt seem to be getting better but probably worse. Oil gauge just seems to sit on 50. I've never done one before so bear with me.

Oil came through tube, and left about 10 inches clear with compressed air I assume? Thats probably normal right? So at high idle and semi-high idle does 50 sound ok? Sounds kind of high to me but stock gauge was always reading between 40 and 80 besides when it dropped off.

I didnt run the car long enough to test if the oil pressure would drop off like the stock gauge was doing. Me and my dad were both checkin it out and we both seem to think the clacking is coming pretty strong from the waterpump.

Used a steth on the front cover as well and also heard it but since pump is attached to front cover duh. Seems pretty dominant from front and center of motor at waterpump. When belt is off I spun the water pump pulley with no problem and no sound.

My dad suggested that the pressure of the belt and spinning could be causing it go off kilter and be hitting the housing or something. Sounds possible to me. I tried to get the pump on as smoothly as possible and with even tightening as possible. I may be pulling the pump back off now and try another but I'd like to see what other people think. The pump was also a rebuilt but Mr. Napa said that he had good luck with that rebuilding company.

One other thing I could mention was that at idle the clacking was something like 4-5 clacks per second and I just lightly goosed the throttle a little and it started clacking kinda violently as if it wasnt bottom end rpm proportional.

start it without the belt on and see what happens... ?

Thats what I was just thinking like 5 seconds ago lol

Let me know how it goes

HEHE You've inspired me...so I just went out and took belt off real quick and fired her up...NO CLACKING!!!!! Gave it a few little revs and no clacks and oil press still at 50. Looks like another fun water pump teardown tomorrow.

Ok wanna hear a funny story? I went out today preparing to remove everything for the pump, and I notice one of the pulley bolts was backed out a little. Tightened it back, found the others were not tight

The bolts for the pulley backed themselves out and that was causing the clacking Sweet

So I ran it for awhile and was doing fine. Kept my eye on the oil press and noticed it finally moved down at one point to about 20 at slower idle and then back to 50 with gas. Then it seemed to settle around 25 another time.

I ran it for about 10-15 minutes and water temp wasnt really rising in between the 220 and 100 mark so I held it at like 1500 rpm for like 30 seconds to try and warm it up and it did. I got it to register a bit past the 220 mark and the fan was still not kicking on. I test grounded it on and held it running for like 30 seconds, went and checked the temp gauge and it was back down to middle of gauge. I said fooey and got my soldering gun out and grounded that green wire.

Now I'll be looking for an aftermarket electric type oil press gauge to mount inside since the factory sender goes for about 30 bucks apparently...ouch

Ouch, did you check/have autozone? I got one there for 10 just about a week ago.

That was pep girls...and special order...discount was order too. Might have to check get in the zone auto zone