Bonnieville died! Please help!
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From: Mississauga Ontario
suck out the coolant from the cylinders and replace upper/lower intake manifold gaskets, mine was leaking coolant internally as well, luckily i found out before i hydro locked my motor 
all Bonneville'* have shitty gaskets so im not surprised theres leaks
the reason for the gaskets to fail is due to dex-cool (anti-freeze) which eats through the crappy plastic gaskets. It took me 2 days to replace the gaskets with a buddy. but after you replace the gaskets CHANGE your oil lol.
BTW forgot to mention clean the upper/lower intake manifolds before you put in new gaskets
all Bonneville'* have shitty gaskets so im not surprised theres leaks
the reason for the gaskets to fail is due to dex-cool (anti-freeze) which eats through the crappy plastic gaskets. It took me 2 days to replace the gaskets with a buddy. but after you replace the gaskets CHANGE your oil lol.
BTW forgot to mention clean the upper/lower intake manifolds before you put in new gaskets
Last edited by Geforce; Dec 31, 2008 at 08:17 PM.
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From: JACKSON, OH
Finally got it together. I still need to finish the coolant. but I have a problem. When I started the car, it runs at fast idle--2500-3000 rpm. I thought it would settle down but it never did. I checked all the connections. Could it be a sensor?
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From: Mississauga Ontario
what happens when you give it some gas for a while then release?
btw replace the thermostat ... dont know if it may fix your overheating issue.
also, when the gauge that reads the Temp. goes high the Bonneville has like an emergency cut off switch to let the car cool down, so it doesnt cook the rings like stated earlier.
That happened to me when i replaced my ignition module, it over heated and for some reason my temp gauge hit high then couldnt start the car anymore (did crank though)
btw replace the thermostat ... dont know if it may fix your overheating issue.
also, when the gauge that reads the Temp. goes high the Bonneville has like an emergency cut off switch to let the car cool down, so it doesnt cook the rings like stated earlier.
That happened to me when i replaced my ignition module, it over heated and for some reason my temp gauge hit high then couldnt start the car anymore (did crank though)
Last edited by Geforce; Mar 10, 2009 at 10:49 PM.
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From: JACKSON, OH
I replaced the LIM using a GM gasket, APN kit for upper, cleaned valley & all gasket areas, cleaned throttle body (BAD!), replaced thermostat, replaced plugs. Got rid of DEX. Car started right up after it got fuel. It then raced to 2000-2500 rpm. After a minute it went to 3k. I'm leaning towards TPS but I don't have a scanner to check. I blipped the throttle a few times but it only made it worse.
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I replaced the LIM using a GM gasket, APN kit for upper, cleaned valley & all gasket areas, cleaned throttle body (BAD!), replaced thermostat, replaced plugs. Got rid of DEX. Car started right up after it got fuel. It then raced to 2000-2500 rpm. After a minute it went to 3k. I'm leaning towards TPS but I don't have a scanner to check. I blipped the throttle a few times but it only made it worse.
Can you drive it to Autozone or another car parts place and have them scan for codes?
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From: JACKSON, OH
Took to auto zone to get scanned. P0121 (TPS) & p0300 (misfire). The misfire was a loose plug wire on #3. I noticed when I was driving arond 45-50 & floored it that it didn't down shift & gradualy picked up speed. TPS is probably sending bad info. Otherwise it ran good. Hopefully the TPS will fix it. Took my other car to get an alignment & they couldn't do it because my outer tie-rod ends are bad. They wanted $350 to fix it! I've got to figure out how to do it myself (2000 dodge intrepid).
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From: Sheboygan Wisconsin
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97 Bonneville
Dear Sir,
Did you check to see if you are getting coolant in the crankcase of your engine? I had a similar problem with my 95 Bonneville and found out I was taking in coolant through the upper intake manifold. What a nightmare.
Ended up rebuilding the entire engine. Hope that is not your problem but 'if' it is and you have coolant in your engine - the coolant will coat the bearings and prevent lubrication and cause the bearings to go out in the engine. Well - that'* what happened to my engine. If you do not have coolant in the engine it sounds like something could be preventing the coolant from circulating through the engine. Check out your cir pump. Is it circulating? If you remove the radiator cap can you see the water move in the radiator when the thermostat opens (when it reaches the appropriate temperature. (Maybe you'll would want to install a new thermostat or test it, while your at it.) I'm not a guru at this but can only tell you of what happened to my cars engine. I couldn't figure it out whee my coolant was going at first either. But I did know I was losing coolant. Hope it is nothing too serious. Maybe it could be a blown head gasket. Look for signs around the head gaskets. Perform a compression check to all cylinders.
Did you check to see if you are getting coolant in the crankcase of your engine? I had a similar problem with my 95 Bonneville and found out I was taking in coolant through the upper intake manifold. What a nightmare.
Ended up rebuilding the entire engine. Hope that is not your problem but 'if' it is and you have coolant in your engine - the coolant will coat the bearings and prevent lubrication and cause the bearings to go out in the engine. Well - that'* what happened to my engine. If you do not have coolant in the engine it sounds like something could be preventing the coolant from circulating through the engine. Check out your cir pump. Is it circulating? If you remove the radiator cap can you see the water move in the radiator when the thermostat opens (when it reaches the appropriate temperature. (Maybe you'll would want to install a new thermostat or test it, while your at it.) I'm not a guru at this but can only tell you of what happened to my cars engine. I couldn't figure it out whee my coolant was going at first either. But I did know I was losing coolant. Hope it is nothing too serious. Maybe it could be a blown head gasket. Look for signs around the head gaskets. Perform a compression check to all cylinders.