urbexHHR

Ok, so it first happened the night of the last Hillsdale g2g when I drove my Lumina. I noticed going uphill it would almost "surge" at times... My first instinct felt like the transmission slipping, but it would only do it around 50mph going up hills, so I concluded that it must just be changing gears and nothing more.

Well now the other day I notice the car seems to be idling somewhat rough. Every 5-10 seconds or so it will "hiccup" but very slightly...not really even noticeable if you aren't in the car, or listening to it. Doesn't sound like it's going to stall or anything.

Well the other night I was coming home from work, and where the speed limit goes from 45-55 I was accelerating, and it started surging or sputtering until I got to speed. It probably did this 4 or 5 times.

Well today I was coming home from school, on the expressway going about 70 with the cruise on and it started doing it again. This time it did it the whole way home, surging and having a hard time maintaining speed. It would slow down, speed up, slow down, trying to hold the cruise speed. One thing I will mention, is just 5 minutes before I had to drive through a deep puddle, and smoke was coming out from under the hood like water had hit the engine... Don't know if that could do anything to trigger this or not...but I don't know since it had been doing it before when dry, now it was just worse.

So I've looked online, and it can really be anything. The car was tuned up when I bought it (2006). I put a new air filter in '07 or '08, and I checked it and it's clean...very clean. I had just put a new fuel filter on this past fall, so I really don't think it would be that. I couldn't see any cracks or anything on any vacuum hoses...

Does anyone else have any ideas?


EDIT: Also, I don't know if bad gas could be anything to do with it? The last time I filled up was before I left for Florida when I put it away. This would have been 5-6 weeks ago. I have about half a tank left, so hopefully I can use it up soon.... Wouldn't have thought it'd get that bad that fast, but who knows since there wasn't any type of stabilizer in it...and it was full. Although this wouldn't explain why it did this in Hillsdale/Hudson, but again that could have been my first thought...gears shifting.

Ivan_Deslayer

I suspect that your car has a MAF sensor. I would start there. Disconnect it and see what happens. If it doesn't have a MAF sensor then take a look at the MAP sensor. Those are the engine feedbacks to the idle speed control circuit or IAC. Those have a direct effect on idle quality and speed. Sometimes a small air leak behind the MAF sensor is enough to give it grief since it's unmetered air entering the engine and the map picking it up as low vacuum. You might also wanna take a look if you're not losing coolant. You maybe getting a vacuum leak due to intake manifold gasket leaks.
Without having a scantool connected and seeing what the sensors are all seeing it's mostly a stab in the dark.

SmootHHR

Driving through deep water can definitely effect drivability. If you got a sensor wet, it could make things act up. The "smoke" you saw was most likely steam from the water hitting the hot engine parts.

My 1990 3.1L Lumina had a wicked studdar/hiccup and it ended up being a broken (dry rotted I think) vacuum line on the top/back of the motor near the back of the intake manifold, just under the plug wires. Replaced that and it was all good. Sounds an awful lot like the problem that we had. We had to replace the computer in ours too...apparently they had many an issue with ecm's in Lumina's. Guess that's why a replacement was only $77. Could be the location under the hood. Not sure if they remedied that in the later models, like yours.

urbexHHR

Thanks for the input guys! I'm 99% sure it has a MAF sensor on it... I'll probably check that first. I do have a scan tool, but it's a basic one, so it really doesn't do much good unless there is a code on. It does say everything is working (fuel air and all that)...

I did see something about the Idle Air Control (IAC). Just need an Ohm meter to check that.... I should probably do that. My grandpa has one of those, and the symptoms of a bad IAC are the same as what I'm having...but then again, the symptoms are the same for many other things too...

Gotta go to work now... Hopefully I'll have time to look at it some tomorrow.

HipHotRod

Arent fuel pressure regulators suspect to this symtom as well?

oneton

I would look at a new set of spark plug wires. Try putting it in drive, hold brake down hard and step on the gas and load it up a little and see if it will miss fire. You did not say u had a service light on .

djr1973

Does your Lumina have the 3.1 liter or 3100 v6(same motor) in it Eric? I had a Beretta that had problems with the IAC (idle air control) it had a bunch of carbon build up on it and caused my car to run and idle crappy.

Doc brown

I would clean the throttle body for sure. GMs are well noted for gumming up and causing rough idle and loss of power. Its cheap and pretty easy to do. Use a can of Gumout carb cleaner. Just be sure not break anything when taking it apart. Make sure to move the butterfly and get all the nooks and crannies. Use an old tooth brush.

A bad fuel pump or clogged fuel filter will cause these symptoms also. Its unlikely that the fuel filter is clogged though. My daughter has a '98 Lumina w/3.1, but I can't say if the filter is in the tank or not.

BlackknighT

My father in law had an early 90s Lumina-your issues had happend to his car but through process of elimination and an old fashioned timing light I had found out one of his coil packs had started to go bad intermitantly after it got heated up. Chevy had put the coil packs on top of the ignition module on the front side of the engine block right near a header pipe. Had a lot of mileage so I changed the 3 coil packs and module (plug & wires too). No issues after with the motor after. The only other problem (had over 200,000 miles on it and just wanted to get another car) was Chevy made the rear spring-yes "spring" out of one leaf of fiberglass that ran from one rear wheel accross to the other. The factory rubber end caps on the fiberglass leaf wore out and had started to crack and split the fiberglass. Help/Motormite makes a repair kit with new rubber ends and epoxy. If your year has the fiberglass leaf look to see that the rubber ends are still in place. If not I can PM you on how to get the new rubbers in. The rubbers should be put back in because if that leaf splits-your in for a whole lot of money...or searching a whole lot of junk yards for a good one.

Mike

PS there was a reason Chevy made the odometers 6 digits (father in laws had em), cause they were great work horse motors. My govment offices had fleets of them from the early 90's that even though they were over 100,000 with abuse they lasted longet than the newer Ford Taurus's we had from 2003-2008. Luminas rode better, had mad leg room, and back then I had a D.A. hair style that never touched the high roofline!

BlackknighT

CrazyCK-when I get a chance I'll check my death trap filled garage (Mother in Law calls it that) to see if I still have any of the repair books for the lumina. I'll give it a shot in a day or so. If I got em-I'll PM you and send em to ya.

Mike