'94 grand am gt won't heat up and all around sucks

[bremen242]

my 3.1L in my g/a doesn't want to get warm. I put a new therm (oem ac/delco) about 1.5years ago, and worked so so... I was getting mad last night because it wouldn't warm up beyond the 1st notch on the temp gauge. (between 100 and 220). When I first got the car, it stayed below the 220 mark... (probably around 200). So, I changed the therm and replaced the o-ring and bypass on the water pump, used rad flush, and filled it with new fluid. it gets warmer now, but still doesn't seem like it is normal.

also, I pulled the front 3 plugs and the middle one was white. Oil looks like oil (no water). I'm wondering if I've blown a head gasket or something..

plus, I keep getting EGR solenoid failures; I've replaced the EGR, O2, the MAP was reading normal, and I replaced the temp sensor behind the therm housing. I also pulled the TB and clean the EGR passage way, b/c it was blocked almost 100%. I also swapped ECMs too, no luck..

I've guessing the EGR might have something to do with the temp problem, but I am not sure..

any suggestions?

[SappySE107]

I dont think the EGR would cause the car not to warm up at all. It would run pretty shitty if it was leaking exhaust gas in at start up and idle. It sounds like the EGR is bad though since its throwing a code, so that should be the first thing to take care of. If it is causing your temp issue though, let me know. Id guess more along the lines of a bad coolant sensor, a clogged up heater core, and/or a stat sticking open.

[geoffinbc]

Do you know what the real temp is(not from the dash guage)? Do you get heat from the heater?

[bszopi]

You are worried cause it is staying below the 220º mark? My engine (before the thermo stuck open) never got above 220 unless I had driven a long while and then got stuck in traffic. It normally stayed right around the 200 mark. Seeing as the thermo is set at 195, it should remain right around that range anyway.

Right now, with my thermo stuck open (or a failed mechanical AutoMeter probe), the temp never gets about 150 and I still get pretty decent heat out of the heater.

[bremen242]

I get heat, but it isn't very hot.

The gauge is fairly accurate, today was around 50, I let the car sit and idle. The gauge would get up to normally, the fan would kick on, and the thermostat would open, and the temp would drop down far. 190-200 down to ~150.

I guess what I am trying to say, is that the car is running like it has a 160 degree thermostat or no thermostat at all, and doesn't run at normal operating temperatures.

You can nail the throttle and run up hill wide open for a while and the car won't get any warmer.

bszopi- 3 years ago when I got my car, it would do exactly the same as yours. leave it idle on an 80 degree day, the temp would shoot to just above 220 and drop ~30 degrees, the fan would shut off, and it would repeat the process, just like it should.

My ford truck didn't have a thermostat when I got it. it made heat, but it would never get above 170 degrees and would drop down a lot when you weren't running it hard. this car acts the same, except not as drastic.

The EGR is not open; the ECM says it isn't opening. I have no clue at all why it isn't working.. It did all the above to solve the problem, and I also checked the harness for shorts and continuity; everything is normal. that problem has been driving me nuts, it seems like ever since the EGR threw the code, the temperature trouble started happening as well.

I think the next thing i'm going to do it check the fuel pressure. If the car is running rich, it'll run cooler, and the tail pipe is relatively black, so I'm thinking it is running rich as well. A guy I ran into said if you have low fuel pressure, your car will run rich b/c the injectors won't atomize right.. is that true?

sorry if this post is rattling on, but I am sick of this thing driving me nuts

[geoffinbc]

Well if you have a signal to the EGR valve then it is obvious the soleniods in the valve have faild. Running rich will make it run cool. But the engine should still get hot if the stat is closed.

[bremen242]

it is a new valve.

defective? I get i'll have to bust out a couple jumpers and a 9V battery to see if it dies @ idle.

[geoffinbc]

Yea I say bench test I guess. Get a 12V source and try each soleniod. Or if you have a scan tool then you can command it open and closed.

[bremen242]

Well, I tested it with the car off, each one clicked, and when the car was running (and with the EGR connector unplugged), clicking each solenoid would drop the idle, from a little, to a heck of a lot..

I'm guessing the valve is working...

how many volts should I have on the ERLS pin on the EGR valve connector?? I think that is the only thing I haven't checked.

[bremen242]

Weird thing-

drove the car ~45-60 minutes tonight. The SEL came on, and I hit my code scanner, and codes 75,76,77 appeared. about 35 minutes into the trip, the light went off, and no codes where stored. Drove the whole way home without any codes too.

the temp is up, but it is a warm night.

the other thing I noticed was it was missing a bit.. When I got to my folk's house, I noticed that spark was arcing down the plug wires and arcing under, over the coil packs. It was damp out, and I couldn't tell if it was the coil pack arcing, or the wires going to the back three cylinders. However, I noticed that the middle wire was arcing, and that happens to be the plug middle that was white.

So, after spending $40 on autolite plug wires (and finding out that they are junk), I want to pickup some good ones and a high energy coil pack. Any suggestions? are there aftermarket ones that are pre-made or do I have to buy accels and cut to fit, and are there any good coil packs?

[TheDirtyBen]

buy ac delco wires. that or spend a lot to get Magnecor wires.
did you bleed the air out of your cooling system? sounds like your cooling system is low on coolant. also, check for kinks in the rubber heater hoses.

[bremen242]

I think I bled out the air.

Is there any special procedure? I run it for 20 minutes with the cap off the reservor and kept putting fluid in it, and run it for a drive, and did it again.

I guess I am going to get delco wires... sounds better than crappy ones.

[TheDirtyBen]

do you have that bypass line connected to the waterneck? or does it have a bleeder valve? there is a bleeder on the top of the heater line that mounts to the water pump.

[bremen242]

I have a bypass line attached to the waterneck and goes to the overflow/filler tank. Do I just pull it off and wait for the fluid to come out?
sorry, I've bled brakes, but never had to do it with a cooling system..

[TheDirtyBen]

no, make sure it's not clogged @ the waterneck. it's designed as an auto-bleeder. i don't think they used them for too many years though. i eliminated mine, in favor of the late-model bleeder valve.
also, while the engine is running and hot, check both heater hoses to see if they are getting hot. if not, you could have a kinked rubber heater hose or a clogged heater core.