SES Light and Engine Dies With Loud POP

[Emmitt101]

Yesterday when driving home the SES light came on in my wife's 97 SE. Then it started blinking and the engine revved a little and started missing really bad. Was only a mile from home and as soon as I pulled in it just died. It restarted after a bit and was missing really bad and light was still flashing. I shut it off and when I restarted it there was a loud pop and it died again. There was a smell and smoke started from the back of the motor. Now all I get is like a "clunking" sound if you try to turn it over and nothing happens. Would the timing belt be the cause of this. I always thought if the belt broke the car would come to a quick stop. The motor is a 3.8 with 140,000 miles. A possible expensive repair?

[maxwedge]

No t' belt here, this sounds like a catastrophic failure of some kind, pull the valve cover off turn the engine by hand see all the valves actuate, possible timing chain issue, or the crank balancer let go, just got to dig into this, no quick answer here. Unusual failure on this engine though, got oil in it?

[pontiac_babe]

Im feelin the grim reeper on this one babe, Might be some Bearings. How was it acting before all of this? Other than the regular GM Motor tick, was it actin like it was low on oil? You know the annoying Knocking. But I would probably bet a bearing or two. I have also known that to happen when the cataletic converter got too clogged up and backed up into the motor, then you might have some problems. book time for a bearing job is like 8 hours so youd be payin like 500 for it. I would really have to hear it. Have you checked the back of the motor to see where the smoke was spewin?

[richtazz]

if you're low on coolant, you may have a UIM failure and coolant got in a cylinder and hydrolocked it. Take the plugs out of cylinders 5 and 6 (the back two toward the driver's side of the car) and look for coolant. If present, the EGR stovepipe warped the UIM and it failed. It's possible that when the engne quit, you may have bent a rod or damaged the piston/crank due to the fact that coolant isn't compressable like air.

[Emmitt101]

Oil had just been changed the weekend before. Not acting, sounding, or driving any differently. Just happened all of a sudden.

[hljmesa]

Also take off the UIM, as mentioned by Richtazz previously, check on both ends and see if the plastic has broken between the coolant and oil area. had to replace the cover on mine last year on a 97 se with 3.8 and 120,000. It was running rough and I needed AC charged. Mechanic noticed a coolant leak. Did a pressure check and then pulled the UIM. Bingo, UIM was replaced and this solved the rough running problem and replaced broken compressor and I was back in business. The engine was pulling coolant into the combustion chambers. Not a good thing and this caused the engine to run rough.

[Emmitt101]

What is the UIM? At this point I'll try anything. Is my wife's daily driver and now she's driving my truck. Help!!!!!!!!!!!!!!!!!!!!

[Emmitt101]

UIM Upper Intake Manifold.

[hljmesa]

Take the gray/black cover off. You unscrew the oil fill cap to remove the gray, flat cover. Then you will notice the round, black cover with the plug wires going over it, etc. Well, this is the intake manifold and, believe it or not, coolant runs through this cover. You will have to remove this cover. There are a number of bolts. Then you will notice what I was previously talking about.

[BNaylor]

Per your request the procedure I have to replace the UIM Plenum was sent.

Note that you can save time by not removing the fuel pressure and return lines to the fuel injector rail. Once bolts are removed just pull and set aside (tie up) the fuel injector rail with the pressure and return lines left on. Otherwse to remove the connectors a fuel line disconnect tool will be needed. If you remove the pressure and return lines be sure to replace the inner and outer o-ring seals. Also, be sure to replace the upper and lower fuel injector o-ring seals.

During assembly make sure the fuel injectors rail nuts/bolts are properly torqued to 89 in-lbs and the UIM bolts in the proper pattern to 89 in-lbs.

Be sure not to forget to install the PCV valve along with the black o-ring seal.

Visit the Tips & Maintenance subforum for additional info on the UIM.

[tblake]

Yes, but he may be wiping his ass before he takes a shit here. I would start with the basics first. Why did it die? Why is it not running now? Like others said, coolant could be leakining into the upper intake and may have filled the combustion chamber. Sorry to say this, but you may have major internal engine damage. Might want to get a compression tester, disable the ignition system, take all the plugs out, and do a good compression test before you go and start buying and replacing an upper intake manifold.

[Emmitt101]

Well..........did the repair over the weekend. Got the intake for $115. Wasn't really that big a deal to replace. Took out plugs and had water come out of one of the cylinders. Not a lot but a little. Used a cheaper oil to check for any more water. Ran at idle for about 30 minutes, drained again and then went with a Castrol high mileage oil. Drove around for a while and had no problems. Should be good for a lot longer. Thanks for all the help. The Forum is a graet way to diagnose your problem and a great money saver for those of us with some DIY knowledge. Thanks again!!!!!!!!!!