Coolant problem, now the shop says I need new intake valves

**barbschwartzer** · 03-06-2013

Bought a 2002 SE about 3 months ago, and after having it for about a month the low coolant light came on. I had almost none in the tank, so I filled it. Well, about a month after that, the light came on again. Filled the tank again, but this time I also bought one of those $1 "leak plugger" tubes to dump in the radiator. Soon afterwards, my engine temp readings started shooting way up at random times and I had no vent heat, almost like the heater core was getting no coolant. The problem seemed to work itself out, but I took it in just to have it looked at.

The car isn't leaking coolant externally (from what I can see), so I thought maybe a gasket somewhere wasn't doing its job. I know that's a pricey fix, and one that these cars are notorious for needing. After I took it to the shop, though, they said I'd need to fix my intake valves and want to charge me $950 to do it. This was shocking to me, as I didn't see any connection between the intake valves and a coolant malfunction; unless, that is, coolant is leaking into the combustion chamber and messing with the engine internals.

Any thoughts? Any help is appreciated. Should I get a second opinion?

**Timing** · 03-06-2013

well even still you could do the valves easy for 1/4 of that
a second opinion wouldnt hurt
im actually having the same problem and i did my lim gasket coolant elbows so idk

**sseilmnop** · 03-06-2013

Car needs lower intake gaskets and probable upper composite intake. Not sure what the shop things valves will do. Take somewhere else or call and ask again, there is a communication problem going on.

P.S. flush coolant system and Replace coolant elbows.

**sseilmnop** · 03-06-2013

Also the car is not leaking coolant it is burning it. It does not need a head gasket!

**barbschwartzer** · 03-06-2013

Thanks for the replies, guys. I'll call again and see if there was a miscommunication. Doing the LIM gasket makes sense to me, doing the valves does not. I'll post again if they insist it's a valve issue.

**dsmuts** · 03-06-2013

Where are you in oh? I could save you some money I've done a few 31/3400 lower intake manifold gasket

**QUICKSILVER462** · 03-06-2013

Just the fact that a shop has recommended a bogus repair "intake valves" should give you good reason to walk away from that shop ASAP.

**LeadfootCJ7** · 03-06-2013

Originally Posted by QUICKSILVER462

Just the fact that a shop has recommended a bogus repair "intake valves" should give you good reason to walk away from that shop ASAP.

Exactly, either they are too stupid to trust with your car or they are trying to rip you off. I would find another shop.

**barbschwartzer** · 03-06-2013

So your diagnosis (without actually having seen the car) are bad LIM gaskets and upper composite intake? I shouldn't have anything else done?

**Scottydoggs** · 03-06-2013

what engine is in this car? 3800 N/a or 3100 or 3400? they can all eat coolant via the intake gaskets.

**barbschwartzer** · 03-06-2013

3100. Had an '03 GT until I spun it into a tree. So now I'm in a 3100.

**L36 Killer** · 03-06-2013

I had the same problem when I owned my '95 Grand Prix (losing coolant month by month, Temp. flucuations, no heat). That car had a 3100 engine. I ended up blowing a head gasket. Turns out that the water pump had gone bad and the loss of coolant was due to it seeping out of the TINY hole in the pump cover. Never saw it until the engine was broken down for repair. Might be worth checking out...

**Scottydoggs** · 03-06-2013

iirc the 3100 does blow head gaskets sometimes, not 100% sure tho. someone will chime in, but they do blow intake gaskets and eat coolant. you may want to do a compression test before doing anything yet.

**coolone** · 03-06-2013

3100 on an SE and blew a head gasket!

**dsmuts** · 03-06-2013

3100's love blowing lower intake manifold gaskets.

**loopy smurf** · 03-07-2013

Yeah - I had a '97 Grand Am GT, and that's one thing I learned...if you're losing coolant and can't find it anywhere under the car, it's most likely the LIM. Those motors LOVE to chew through their LIM gaskets. The water pump idea isn't bad either, and insanely easy to do on that motor. Water pumps are cheap and easy (the way I like my women), so do that and the LIM, and that should fix you up.

**RareGMFan** · 03-10-2013

Head gaskets are not common on a 3100/3400 unless something else went wrong (eg. L36 Killer's water pump issue). Regardless, as Scottydoggs suggested, I'd get a compression test done first to rule it out completely. If everything checks out with that, I would say there's a 99% chance it's the LIM gasket, which almost any GM motor from the '90s and early '00s are notorious for. I recommend getting an intake gasket kit which should also include valve cover gaskets, EGR gasket, etc. If you're in that deep already, might as well change everything out. It won't cost much more. Here's an excellent video on how to do the job with plenty of details.

Intake Manifold Gasket replacement GM 3100 V6 95' grand Prix - YouTube