Okay on Tuesday my vacuum controlled heater valve broke. I was driving and all of a sudden a huge cloud of steam was rising from my hood. So I pull over, pop the hood, and the plastic on the valve was snapped. Coolant went everywhere. The water pump pumped the radiator dry. I get the car towed home and hose out the engine then wait a day for everything to dry. The next day I changed the valve, filled the coolant and start her up. The problem is the ideal is rough and the RPM’s go up and down by about 100.

------------------
1989 Iroc-Z 5.7 350, Blue, T-Tops

Lightly Moded:
Edelbrock Headers, Rebuilt B&M 700R-4 Tranny, Higher Stall Torque Converter, Airfoil, 3.4 w\posi, K&N's, Ported Plenum
-- Blue LED Bakelite Dash & Climate Control
"Just some 17 Year old spending every dollar I make on my car."

 

Remove the distributor cap and rotor. Wash the cap and rotor in very hot, soapy water and rinse in very hot water. Allow it to dry completely before reinstalling it. You could also inspect the distributor ends of all the spark plug wires, coil wire, and inspect the coil for signs of moisture.

You should also inspect the wiring in the base of the distributor for moisture. Rinse with very hot water, alloy it to dry, of assist the drying with a handheld hair dryer or heat gun. When the distributor base is clean and dry, apply a little demoisturant spray like CRC 5-56, or WD-40. CRC works better for moisture control, but both will prevent rusting and help with any remaining water.

When the distributor is finished, do the same with the coil. Reassemble the cap and rotor, plug in the clean wires, and start up.

It is likely that some of the coolant mixture contaminated the ignition system. The coolant will not exaporate like water, so it can continue to cause electrical problems for a very long time if you allow it to remain. You'll have to get in there and clean it out or suffer with misfire forever.

------------------
Later,
Vader
------------------
If you want to beat the World, it might reach up and pull you down...
Adobe Acrobat Reader

 

Thanks Vader,
I replaced the distributor cap and rotor today because they were in pretty bad condition. The car runs a smoother but when it heats up it starts to idle rough and shake. The weird thing is the car seems to have good power still when you floor it. It feels like it is going to stall when you come to a stop too. Any ideas?

 

TPS sensors dont take well to water baths. Might want to check it out.

 

TPS sensor reading okay. Any more idea's?

 

mine's broken before too. I'm gonna replace or remove it one of these days. Do other cars have a metal one?

 

I had that once, an intake leak and anti-freeze bath on the engine. Fixed it all and thought I had a vacuum leak or something else wrong, timing, etc. I checked everything. Turned out the O2 sensor must have not liked the coolant, or it was just its time to go. I changed the O2 sensor and everything was back to normal. Just my experience and may not be your problem. Like you, it still ran pretty strong, just seems to be a bit rough at idle and slight acceleration at times.



------------------
_ ___ _
SMasterson

 

Setting any codes? SES light on? A slightly stuck open EGR valve can cause symptoms like the ones you describe......

------------------
1987 GTA L98 MD8
355, TFS Heads, LT4 Hot Cam
My GTA

The Minnesota F-body Club

 

Nope the SES light is not on. Whats a easy way to check EGR?

 

I'm not sure what it could be, my guess would be related 2 the hosing down of the engine bay depending on how much water splashed around. But I wanted 2 ask 4 myself - which way does the coolant flow in the hose that goes from the heater valve 2 the TB? I'd like 2 run off of a short style water pump if possible.

 

It flows from the intake to the TB, to the valve, and then to the radiator. The heater core will be inbetween the valve and radiator when the valve is open.

 

i just broke mine the other day as well. if you check back on this tech board im sure you can find my topic and the guys there talked about a metal replacement that was used on older chevy trucks.

 

------------------
-Tas
'89 Formula WS.6