Trouble with a '98 3.8L

[StuntmanMike]

Hey everybody, I'm having trouble with my '98 3.8.

It's not in an F-Body, but in a Olds 88. I figure it doesn't hurt to ask here, it's basically the same engine.

Problem started a few months ago. I was driving home one day, and the SES light started flashing, and then the car started running rough. I shut it off at the store, and when I went to leave, it was hard starting, but it did start. I went home and parked it, intending to take it to a shop the next day. Next day, it wouldn't start at all. It turned over fine, but wouldn't even TRY to start.

Had it towed to a shop, he changed the plugs (I have no idea how old the ones in there were), and said that did the trick. He also asked me if I noticed that it "smoked like a bastard". I actually hadn't. Although since then, I HAVE noticed smoke. Not a huge amount though.

The car started up and seemed to run fine, but the SES light was still on. When I got home, I disco'd the neg batt. cable for the night, and that shut it off. The next week it came on again, with no syptoms. I took it to Autozone, and they pulled a code. I forget the number, but it was for "multiple cylinder misfires". After they pulled the code, I guess that cleared it, because the light did not come back on.

It was fine for a few weeks.

Then the light came on again, and the car would run slightly rough. I also noticed when the light was on, the car would run very hot. Normally the temp gauge doesn't move past center, but when the light was on it would creep up to 270, untill I turned the A/C or heat on. (AC engages the 2nd cooling fan).

This problem was intermittent, happend a few times in 3 weeks.

I started to think it was plug wires, so I changed those. Car ran fine, so I didn't know if it helped or not.

Apparently not.

Three weeks ago, I was heading to CT, when the car died on me (no light, just died while taking an offramp). After about 15min I was able to get it started, but it was running very rough. I was able to get home and get my Jeep to make the trip in that.

I let it sit for the weekend, and it seemed to run fine. I wasn't driving it though, I was trying to figure out what to do with it.

I decided to run an errand with it, to see how it was running. Started off okay, then it started running a little rough. Parked it where I needed to go, and of course it wouldn't start. Ended up having it towed the next day (different shop. The first one was recommended to me, but it turned out the guy specialized in classic Merceded Benzes).

They call me later in the day, they said it's running, they had to replace the plugs (WTF, had this done a month and a half ago?). They said that didn't cure the problem though, because it will still die after a while, once the module gets hot. They said it needed ignition module and all 3 coils. Parts and 2 hours labor = $735.

HELL NO!

Bad enough they charged me 300 bucks for diagnostics and a set of plugs. Frickin' A-holes.

I ended up going to a pick-your-part junkyard and pulled the module and coil packs off a '97 Olds 3.8. Came out to 32 bucks, with the warranty.

I like how they were going to rape me for 2 hours labor, it took me about 20 minutes to swap the coils and module.

Just to clarify, the module is the flat piece the cil packs plug into?

Anyway, car starts up just fine, no SES light (yet), but still seems to run a bit rough at low rpms. It'll idle rough, especially in gear, but seems to smooth out past 2k rpms.

Also, I had it running today and checked the oil after I shut it off, and there was smoke coming out of the dipstick tube.

The oil doesn't look right either, I was thinking water at first, because that thing goes through a LOT of water, but doesn't leak it. (I've been running straight water in it the past few months, it seems like I'm always adding, so coolant was getting expensive) It's not milky though, and there isn't any froth under the oil fill cap. I'm thinking it might be fuel, because I cranked the hell out of it trying to get it to start last time it died. Maybe it got past the rings.

Sorry this is so long, but does anyone have any ideas?

Oh, car has 113k on it, the motor has a bit less, as it was replaced when the car was in the mid 70's. I'm not sure exactly when, as the person who gave me the car doesn't remember. It's also on it's 2nd replacement tranny, once again, replaced before I owned the car.

Right now the car is my DD, but at this point I just want to get it running decently so I can get rid of it and pick up an SS.

[Street Lethal]

Had it towed to a shop, he changed the plugs (I have no idea how old the ones in there were), and said that did the trick. He also asked me if I noticed that it "smoked like a bastard". I actually hadn't. Although since then, I HAVE noticed smoke. Not a huge amount though....

You should have asked for the old plugs back, as their condition would help determine if your running too lean, or too rich. When the SES light is triggered, the ECM runs on predetermined VE's (which some people refer to as "Limp Home Mode"), slightly rougher idle (because of the added fuel), which smooths out as RPM increases....

The car started up and seemed to run fine, but the SES light was still on. When I got home, I disco'd the neg batt. cable for the night, and that shut it off. The next week it came on again, with no syptoms. I took it to Autozone, and they pulled a code. I forget the number, but it was for "multiple cylinder misfires". After they pulled the code, I guess that cleared it, because the light did not come back on....

Are you running the stock coil packs...?

Then the light came on again, and the car would run slightly rough. I also noticed when the light was on, the car would run very hot....

Again, when the SES light is triggered, the ECM runs the engine on predetermined air/fuel/spark settings. Was running hotter because of the timing being pulled, again due to "Limp Home Mode"....

Three weeks ago, I was heading to CT, when the car died on me (no light, just died while taking an offramp). After about 15min I was able to get it started, but it was running very rough. I was able to get home and get my Jeep to make the trip in that....

Anyway, car starts up just fine, no SES light (yet), but still seems to run a bit rough at low rpms. It'll idle rough, especially in gear, but seems to smooth out past 2k rpms. Also, I had it running today and checked the oil after I shut it off, and there was smoke coming out of the dipstick tube.

The oil doesn't look right either, I was thinking water at first, because that thing goes through a LOT of water, but doesn't leak it. (I've been running straight water in it the past few months, it seems like I'm always adding, so coolant was getting expensive) It's not milky though, and there isn't any froth under the oil fill cap. I'm thinking it might be fuel, because I cranked the hell out of it trying to get it to start last time it died. Maybe it got past the rings....

What color was the smoke, and was there an accompanying sweet smell? Honestly sounds like an O2 sensor related problem here. If it's not corrected, it doesn't matter how many new spark plugs you throw in, because they'll eventually go bad (due to a faulty reading)....

[mikes2002z28]

hi mike if u have 2 keep adding water it might be the intake gasket.they are know 2 leak and that will cause it 2 misfire and u will see smoke from tail pipe. another possible thing it might be is a head gasket. i would have the cooling system presure tested. mike

[StuntmanMike]

Thanks for the info.

Yeah, I realized later on the next day I should have asked for the plugs back.

I'm running stock type coil packs, I got them out of a '97 Olds 3.8 in a salvage yard. Two are stock GM, the 3rd is a Standard replacement unit.

I've read on other sites about the intake leaking, I'll have to check that out. I guess the only way is to pull the intake and see.

At this point I'm running straight water in it, so the smoke doesn't have a smell.

The linp home mode makes alot of sense in explaining why it runs hot when the SES light is on.

Also, I tried to start the car the other night, it wouldn't start. It started to crank, made a funny noise that I didn't hear, but a friend outside the car did, and after that all I could hear was the solenoid clicking. I tried jumping it with my Jeep, but I couldn't get it to turn over, just click, click.

I doubt the battery was dead, it started fine a few days before after sitting for a week, and I know I had a good connection with the cables.

Oh well, I wonder how hard it is to change the starter.

I'll try jumping it again first though.

Thanks again for the info.