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93 Grand Prix Coolant, Voltage issues

Hey everyone --

I have a 93 Grand Prix LE with the 3.1 V6, VIN "T" engine. I have two problems that I haven't been able to figure out yet:

1) The voltage steadily drops when from cold start to driving. At a cold start, it's at about 14V... it steadily drops down from 14V to 12-13V (while driving and hot) and to about 10V when at idle or a breaking stop. It doesn't go back up to 14V until it has been sitting and cooling down for 8 or 9 hours (well, that's my work shift at least :)).

I've tried replacing the alternator (in december), the ECU (in June when the car died completely and wasn't getting any electricity), and the battery couple weeks ago. The ECU replacement seemed to keep it above 12V for a few weeks, but it's right back to where it was before now. Any ideas? Where to start?

2) The coolant is leaking out from underneath the coolant reserve tank. The leak is below the ECU, but it's leaking like a sieve (a full gallon in 10 miles of driving.) There is a metal line underneath there that I want to call a "coolant return line", but I haven't been able to find anything at the car parts stores or online stores to replace this. Or am I going about this the wrong way? They have this $60 bottle of "blue" sealant that is supposed to seal up everything nice and tight... or is this just a waste of money? The cheap-o coolant system sealers seem to be useless regardless of the situation from what I've found.

Thanks! Shaun

Reply to
shaun
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I take it your Battery is going dead during this time ? hard to beleive the 10V because of the battery unless it is going dead. What is drawing all that current to cause this ? joeG

Reply to
joe_goodart

The battery actually doesn't go completely dead usually. (it's happened twice I think in about 6 months.)... which is strange to me too.

I have no idea what's drawing all that current... it's really strange because it's not low all the time... it's fine at a cold start and gets progressively worse.

Maybe a short would cause a drain like this? But then why is it fine on a cold start? And where to even start if it is??? I just am out of ideas after all I've replaced and putzed around with on it to get it going. Would a bad relay cause this maybe?

I hooked up a code reader to it today and got a code 12 and a code 32. The code 12 is an "all pass" indicator I think... the code 32 has something to do with emissions maybe?

Reply to
shaun

wrote

Are you just looking at the guage and believing what it's telling you, or have you actually checked what the voltage is doing right at the battery. I say this because the clusters in the older W cars were notorious for inaccurate guage readings.

Another common problem with the W cars, that line "is" the return line from the heater core, it runs along the passenger side of the body inside the engine compartment and usually rusts away at the points where there are brackets welded to the pipe. You probably can only get that hose from the dealership. It's also fairly nasty to replace if you have never replaced one.

Ian

Reply to
shiden_kai

What are you using to come up with this voltage? The gage on the dash? I cant imagine your under the hood taking these readings and driving at the same time.

$60 dollars??? Return that thing if you can! The only stop leak I use and recommend is the tablets GM provides. Can you take a picture of this line because I cant visualize what or where your leak is but if its a bad leak no stop leak in the world will seal it.

Reply to
Bon·ne·vil

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