turismo

No one responded to my previous post so I'll try in here if its more suitable.

history : car was overheating in the past. I figured it was the thermostat and changed it yesterday. I let her run for about 4 minutes or so and she stalled out. She would start right back up but then die again. If I throttle it at 1000 rpm she'll keep going, if not it'll drop to 500 rpm and die.

I figured it was heat or something like that because it was pretty warm out. So I come home tonight and start her up and the same thing happens. Starts and dies.

I really need help here guys because there's no way I want to take her to a mechanic right now.

Haynes says to check for vaccum leaks and check for possible leaks around the intake manifold. Could it be that I botched the thermostat install?

And one more thing. I'm not sure if this is a new thing but it sounds like I hear air hissing from somewhere, I could just be paranoid and it's the belts making the noise.

Any ideas would really help me out.

Thanks

-simon

thegig

1. Try looking for the vacuum leak. The hissing may be a vac. line or a seal gone bad. Using an UNLIT propane torch seams the preferred method (other than a vac. tester). Go around all the vacuum lines and see if the idle changes at all.

2. Test the fuel pressure/injectors

3. EGR

4. Timing. I noticed when the timing was off on one of the vehicles I was working on, there was a hissing sound as it was sucking to stay alive . The sound leveled off when I reset the timing.

Red Devil

Disconnect your maf see if it stays running (albeit crappy). If so you have a MAF or MAF relay problem. Have you pulled codes? Have you tested fuel pressure? Get a can of carb cleaner/starter fluid/etc. and use it to find any vacuum leaks. Review your vacuum diagram under your hood and make sure there is no deviance between it and your routing.

turismo

I can disconnect the maf. And maybe even check fuel pressure. But the other stuff a mechanic would have to look at.

The car was running fine before I put in the new thermostat other than the cooling issue while driving.

What about my temp gauge not going up. It goes up a tiny hair and stays there. Could my gauge be broken at all?

Red Devil

You should be able to do anything in my post, except maybe test the fuel pressure if you don't have a gauge.

Codes can be pulled with the GM OBD I Diagnostic Code Retrieval Tool... commonly referred to as a paperclip here on TGO.

Take the carb cleaner/starter fluid and spray around the engine, when the idle goes up, you've found the area of the leak and you can then try to narrow it down.

Did you install the t-stat correctly?

turismo

I'd have to buy a gauge, I'd have to buy a code diagnostic tool as well.

And I really don't know if the t-stat is in right.

I took it out and replaced the old gasket which was just tearing up while I was pulling on it. It was like a wet paper bag tearing.

I cleaned off the area and made sure nothing fell into the manifold. I added some sealer to the edges and put the elbow back on and then tightened the 2 9/16 bolts. Which are a freaking bitch to get too because of all the crap in the way.

To me that all sounds correct. I put the t-stat in exactly like the other one. Both t-stats are made by motorad and are both 160's.

When the motor was hot the upper rad hose didn't have any heat to it. It might of been a bit warm but that could of been from the engine itself warming it up.

I can go outside now and check the MAF. I have the intake elbow that goes to the throttle body off. I doub that matters does it?

Red Devil

That elbow has to be connected in order to have the car function properly, otherwise the car can't measure the air flowing in.

--You only need a paperclip to read codes.-- Search for 'diagnostic' and Red Devil or Vader and you'll find Vader's novella on how to do it along with a link to a pdf list of the codes.

What type of sealer and what type of gasket. Sounds more or less right to me... except the 160º

turismo

One more thing I thought of is bad fule. The car sat for 2 years and the gauge says just past half. So it might be sucking something from the bottom of the tank.

Just a thought

Green92RS305

gasoline usually is only "good" for about 3 months without a stabilizer adative. after that it becomes real crappy, drain out that old gas and stick some new gas in there IMO

turismo

I agree. I'll see if I can change the fuel filter too. It could just be that the pump sucked up some bad gas the same time I was doing the t-stat install.