Need advice on a few things with my '98 3.8L

HI guys, after searching through this forum for the info I needed, without success, I decided to mail the forum for help.

Although I can find several links to issues with UIM and LIM issues I can't find a description of the procedure to replace those gaskets, they're are a couple of links but they appear to be dead.

I have a '98 Olds Intrigue GL in great condition. I bought it in California in April 2004 with 65,000 miles and it ran great until recently when the low coolant light would flash on and off. Checking the oil showed the level was very high, well above the "full" mark. I am very careful when changing and checking oil to make sure the levels are correct.

So based on info on this forum I guessed that my gaskets were leaking and getting in to the oil. I got a list of receipts from the dealer when I bought the car that showd they had already changed the UIM and LIM in March 2004 before they put the car up for sale. So it looks like they didn't last too long!!

So a few questions that I'd really appreciate the forums help with.

1)Is there a procedure available here (somewhere) that details the remove and replace steps for the gaskets.

2) In preparation I've removed certain parts (fuel rail, airbox, electrical connections) I also removed all the bolts on the intake manifold but can't get it off!! There are two arrows pointing to "hidden bolts" but there is nothing I can see - I am missing something really obvious? Giving the manifold some gentle persuasion did nothing to budge it.

3) where can I find the coolant level sensor that signals the "low fluid" dash light to flash? I read that they can get dirty (with dexcool) and cause probs.

and finally

4) before I started all this pre-emptive teardown, I drove the car a couple of times and it suffered what felt like a mis-fire. I noticed this a few times especially when I was driving up a steep hill. Is a misfire a typical symptom of this issue? What are the typical symptoms that folks have had. Does this sound like I have fluid in one or more cylinders?

cheers

Blair

The misfire could be something as simple as fouled plugs (likely if youve been burning coolant) or bad wires. Id lean with the wires especially since you say its worst when your chugging up hills.

I believe the coolant level sensor is on the driver side of the radiator, up at the top, its on one side or the other haha.

As for the replacement procedure, I sent you some links via private message, so youll have to check that out. Should be a "Private Messages" link you can click below your username in the upper-right of the screen.

I feel your pain! I just did my UIM on my '98 this week. My car "hydro-locked" and wouldn't restart at all. There are great procedures to do this online, I am sure Little Hoov hooked you up. Is the car already converted to the "green antifreeze"? I had switched mine 2 months back when I did the Water Pump. Make sure you replace the UIM with the Dorman kit # 615-180 ($150.00@Autozone). This is the better than original design. This is the kit that all the reputable shops go with. Be sure to change your plugs($7/ea) and oil, and let the car idle for 15 minutes so that residual coolant burns up(will blow white smoke a little bit). Good luck keep us posted.

P.S. the kit tells you to torque the UIM Plenum in a specific order, 3 times around, to increased "inch pounds". This tool has to be adjustable from like 24 to 90 "inch pounds". Azone didn't carry this tool so i had to improvise.

I have a '98 Olds Intrigue GL in great condition. I bought it in California in April 2004 with 65,000 miles and it ran great until recently when the low coolant light would flash on and off. Checking the oil showed the level was very high, well above the "full" mark. I am very careful when changing and checking oil to make sure the levels are correct.

How high above the full mark? How many quarts of oil did you put in? It should be 4.5 qts with filter change. What other symptoms do you have indicating UIM or LIM gaskets? Any sludge on the back of the radiator cap and inside the radiator filler neck? Any brown milkshake look on the dipstick? Check the back of the oil filler cap and look for condensation or signs of coolant. Any confirmed coolant loss at both the reservoir and at the radiator?

The coolant level sensor is located on the passenger side of the radiator about 3 inches below the top of the filler neck. Easy to remove and clean. Old sludge will stay on it until it is physically removed and cleaned up. See pic below.

If you need any help just reply at this thread asking for it to benefit other members or send me a PM. I've done a total of 6 UIM/LIM jobs on the Series II 3800 engine with plenty of pics.

Note: The hidden bolt markings on the UIM are referring to the two outer diagonal LIM bolts which have nothing to do with removing the UIM. Make sure you remove all of the UIM bolts (total of 10) and then pull up hard on the UIM.

http://i5.photobucket.com/albums/y186/lizzywiz/DSC04043.jpg

Hi, thanks to everyone who gave me suggestions on the UIM/LIM removal process. Your help was invaluable. Here's the status so far.

I finally got both the UIM and the LIM removed from the car. It certainly appears that both of the sets of gaskets were recently replaced. The UIM gasket is black plastic surround with orange gasket material, it appears to be just fine no sign of sludge or degradation on the orange material.

Likewise the LIM gaskets appear to be the new aluminum ones that are required, green gasket material and aluminum surround.

Additionally the intake manifold itself is the original but shows no stress, wear or cracks in the area of the stovepipe or anywhere else for that matter.

So where did the coolant in the oil come from? I suspect it's one of two areas, possibly both.

Firstly the throttle body and TB gasket have dexcool type crud on them at the area where coolant would enter the TB cooling chamber. I suspect that's where it's been leaking. On the TB itself it looks like either old gasket or dexcool crud has not been scraped off and I suspect that the TB to intake manifold seal effectiveness has been compromised allowing coolant into the UIM and then the LIM.

Secondly the LIM gaskets that mount on the ends of the manifold appear to have been installed upside down! From the photos I've seen on this board the end gaskets appear to install on to the engine with the orange gasket material facing up. The LIM then sits on that and squashes the orange gasket material sealing the joint. In my case, after removing the LIM and turning it upside down the orange material is the first thing you see. Both the main LIM gaskets and the end gaskets are stuck on to the LIM itself not the engine. I'm not sure if this really makes a big difference or not when the seal effectiveness is considered but I mention it anyway.

Given that these are the new LIM gaskets am I safe/wise to leave them on the LIM and carefully refit it back in place? Or should I bite the bullet and buy another set and fit them.

I also noticed that the thermostat is a 195C version without a breathe hole. I will pick up a new 180C one along with a t-stat housing gasket, new TB gasket and injector O rings. I am planning to reuse the UIM gasket but as mentioned above not sure about the LIM gasket. I will also remove the Dexcool and run the green "mixes with anything" type in its place, change the oil (again) and plugs. The IM looks almost perfect for an original '97.

thanks guys, any thoughts/comments gratefully received.

Blair
1998 Olds Intrigue GL

HI guys, I just realized a typo in my very first post. The UIM and LIM gaskets changed by the dealer (before I bought the car in April 2007) were changed in March 2007!! Not March 2004 as I initially said. So the gaskets are just over a year old.

Bnaylor, thanks for the photo of the coolant sensor. I did find it and it doesn't look very cruddy at all. So I'm sure it's been correctly reporting low coolant.

When I change the oil I always check the manual for the correct capacity including the oil filter. 4.5 quarts was what I used which brings the oil level up to the max fill line (or just below). The levels I saw were way way above the full mark which gave me my first indication that I may have coolant in the oil.

The radiator cap did have some Dcool crud but not much and there was some more at the neck of the radiator. The dipstick was clean other than showing a very high level as stated above.

thanks again guys.
Blair
1998 Oldsmobile Intrigue GL

To be honest with you I am not a fan of GM/Delco UIM or LIM gaskets whether the old style or revised. Plus there is anecdotal info on the Net that SII 3800 owners are experiencing failures on the new aluminum framed LIM gaskets. I use strictly the FelPro aftermarket brand gaskets. See pic. And I would not re-use any of the gaskets. You've gone too far to have to re-do it all over again.

On the LIM end seal gaskets do you have the pinned or unpinned? What you explained sounds weird. Look for the holes in the top of the engine block where the LIM will rest. On the pinned end seals the tits in the black part of the seals will face down into the holes so the orange part will be facing up. Also, make sure you use a good sized bead of hi-temp RTV silicone seal at the 4 corners where the LIM port gaskets and end seal gaskets meet.

http://i5.photobucket.com/albums/y186/lizzywiz/DSC02591.jpg
Latest FelPro LIM Gasket Kit for SII 3800 Engine


This how it will look with the port and end seal gaskets properly installed using the FelPro brand as an example. These end seals are the pinned. Part number MS95809-1.

http://i5.photobucket.com/albums/y186/lizzywiz/DSC02593.jpg

Hi, thanks for the follow up. I've included a couple of photos to clarify what I'm seeing. The engine block does have the mounting holes for the end gaskets as you can see. The gaskets are firmly stuck on to the LIM itself and I would be worried about re-using them in any event.

Has anyone else had the TB gasket itself cause issues and leaking in to the cylinders?

thanks again for your responses.

Blair
98 Olds Intrigue GL

file:///C:/Documents%20and%20Settings/Blair/My%20Documents/My%20Pictures/oldsmobile%20photos/SANY0052.JPGfile:///C:/Documents%20and%20Settings/Blair/My%20Documents/My%20Pictures/oldsmobile%20photos/SANY0052.JPGhttp://s452.photobucket.com/albums/qq248/bgilgall/?action=view&current=SANY0053.jpg

http://s452.photobucket.com/albums/qq248/bgilgall/?action=view&current=SANY0054.jpg

http://s452.photobucket.com/albums/qq248/bgilgall/?action=view&current=SANY0057.jpg

UPDATE:

Finally! After being sidelined for days with other projects I've managed to get the Olds back together after replacing the UIM, LIM and TB gaskets, the canister purge solenoid and some vacuum lines. I also replaced the DEX with "use with any type of antifreeze" and fitted a 180c thermostat (drilled a hole in it too).

The car has started and ran just fine while in the garage as I fill it with coolant and try and bleed the cooling system. Levels in the radiator and expansion tank are normal but I continue to get a flashing low coolant light on the dash when the car is up to temp (this is while the fluid levels are where they should be).

When the radiator was empty (before I filled it) the low coolant light was on solid as the fluid level was below the sensor level. But once filled it flashes away, sometimes staying lit for a longer period of time before it flashes off and on again. Note that the radiator cap was not fitted as I ran the car and fed in coolant to the system.

Googling "flashing low coolant" shows a number of people have had this issue (mostly with GM cars) but nobody has posted the fix to this issue, whether is was wiring, bad sensor etc. When I had the car torn down I removed the sensor and cleaned it, it didn't look too bad anyway!

Anyone here had this issue and can share the fix?

thanks

I had the same problem with the coolant level sensor on 2 different cars. Each time, removing and cleaning the sensor was the fix. Good Luck! :smokin: