Did I get jacked by my Garage? 97 Grand Prix

[upmm019]

Hi,

I have a 1997 Grand Prix GT (Vin K) that I had serviced back in January as it had an external coolant leak.

The repair shop charged me over $700 for the repair but they also said they needed to change out the intake gaskgets.

Well long story short the engine no longer leaked after they fixed it but just three weeks ago the engine threw what we think is a rod bearing or main bearing.....

After further investigation.... seems these 3.8L engines have issues with the upper plenum and something with the EGR that causes and internal coolant leak....

That said, should have my garage check/replaced that upper plenum as a precautionary step since they already had it off??

I just laid down $1200 for a used engine minus any labor to install it and want to make sure I don't encounter the same flippin issue.

My used engine warranty requires intake gaskgets to be replaced but I think I should have the upper plenum replace or have that EGR item fixed so it does not melt causing that internal coolant leak.....

If you have two cents on this... please share it with me.....

[jakegday]

if you dont let your cat get bad, you wont have a problem with the egr causing the intake plenum to melt
you can get an upper intake plenum brand new for $60 at zzperformance.com

[upmm019]

What are you trying to say here??

** "cat get bad"

Cat get Bad... what does that mean?

[richtazz]

By cat, he means the catalytic converter. The 01-02 GP's had a known issue with the converters failing , but this doesn't apply to your 97 model. The plastic UIM's are a known issue with 95 thru early-99 3800's, so your garage should have known to check the UIM while they had it down for the LIM gasket change . The problem is the EGR stovepipe was too close to the surrounding plastic, and it caused it to melt and deform. This would cause an internal coolant leak that when left unchecked, could cause coolant hydrolock due to coolant getting in the cylinders (usually cyl 5 and 6). Since coolant can't be compressed, it causes bent/broken connecting rods. Later redesigned UIM's had a larger air gap around the EGR stovepipe to correct this issue.

[upmm019]

I looked at the invoice they gave me and they replaced the following GM parts/gaskets

• 89017554
• 89017817

I believe one of those is the lower intake and the other is the gasket for the upper plenum.

Like I said right now when you start the car it knocks really loudly. I think it was drove this way for a few miles as my son was out driving when the knock started.

Checking the odometer he put 6k miles on since the work was done for the coolant leak.

How does one determine if they didn't do correct preventive work that ultimately resulted in this engine knock??

I'm really PO'd at them and even after my son took the car in when it had the knock they acted like they didn't even want to work on it but yet back in January they took over $700 bucks from me.....

I just think there should be some accountablity for this issue.

[tblake]

I think an Upper Plenum would take more than 6k to melt enough to fill the cylinders. That seems too soon. Did you check your coolant level? Is if full or low? I would be half tempted to pull the UIM myself and see if its melted or if the gasket was just installed incorrectly causing a leak.

[upmm019]

well, what happens to the engine if the cylinders fill up?

What I was tolds was the coolant gets into the oil and it wipes the bearings clean so there is no lubricant.

I think it's just so strange, it was such a solid running engine and then to have it just start knocking has me baffled.

I'll have to check the coolant levels. I just parked it out at my father-in-laws acreage until I figured out what I was going to do with it.

I talked to another dealership in my area and they said there was a Technical Service Bulletin on that upper plenum and says they should have considered changing it out.

[richtazz]

The 2 part numbers you gave above are just gaskets. They didn't replace the actual UIM (Upper Intake Manifold), just the UIM gasket. On pre-99 Vin-K 3800's, the UIM is the most common failure part that causes internal coolant loss. An inspection of the coolant passages around the EGR stovepipe, looking for erosion (they will look pitted and rough instead of smooth) as well as deformation of the surface of the UIM, should have been done instead of just replacing the gaskets. On Late-99 and newer 3800's after the GM UIM revison, the gasket was the weak link. However, if let go long enough with a bad gasket, the resultant coolant leak will erode the UIM even on the newer design, requiring UIM replacement as well. The only way to know for sure is with a thorough inspection.

[upmm019]

Thanks for the information.

I feel like I've been jacked by my garage. I feel they are the professionals and should have known about the issues with the 3.8l and the fact there is a TSB on the upper plenum. Although the TSB is just an advisory it seems like this is a leading cause to engine failure if not addressed.

What would have been the big deal about spending another 150 dollars on in for preventive??

That is where I think they failed and I feel like I'd like to go to court over it.

[wlkjr]

Originally Posted by upmm019

Thanks for the information.

I feel like I've been jacked by my garage. I feel they are the professionals and should have known about the issues with the 3.8l and the fact there is a TSB on the upper plenum. Although the TSB is just an advisory it seems like this is a leading cause to engine failure if not addressed.

What would have been the big deal about spending another 150 dollars on in for preventive??

That is where I think they failed and I feel like I'd like to go to court over it.

Sounds like you were way overcharged for what they did. As far as going to court, you're going to lose that one so you might want to save those dollars for something else. Next step would be to find a better garage.

[richtazz]

If an inspection of the UIM indicates it is in fact eroded, and the resultant coolant leak is found to be the cause of the damage, then I think you would have a case against the original garage that did the LIM job. They should have done the inspection and found the issue. It is possible that you just have bad luck and the engine grenaded shortly after the LIM repairs were done due to no fault of the garage that did that work. Sometimes used cars are used up, and there is no indication that they are about to let go.

[randy78]

way too much labor charge man wow

we own a garage and work on these 3800 engines all the time and have also replaced countless ones with used engines we pick them up for around 600 or less at a given yard and always run great and great for years.

we just picked up a spotless mint condition 2000 something bonneville from a lady who had her 3800 engine blow up the entire upper intake because apparently on these engines the fuel pressure regulator is also crappy and will rupture internally and allow fuel to get sucked into the intake and then when you crank to start it there will be a mis timed spark and it blows the top end and the intake is the weakest point,.

giving 400 for the car and going to replace the intake and entire rail and MAF and then sell it for about 3k


the upper intake melting due to bad egr pipe design in it is a common issue on these as well yes.

great engine probably the best v6 engine gm ever made but the engineers designed some problems when they re designed them to be the series II style

going to cheap plastic and trying ot run hot exhaust through it

dumb..

even engineers fail, often.