99 lumina computer problem???? Our 99 lumina stopped running and now when we try to start it, it turns over slowly, but sounds really rough and won't stay on. We plugged a code reader in and it wo

i think you need a new starter. my suburban cranked really slowly as well, a new starter fixed that problem

Coil, plug or spark plug wire

I would check the EGR valve first........Hope this helps.

This sounds to me as though you have a mixed up computer chip in the onboard computer controling the shifting. First though, check the RPM sensor on the tranmission. If it is sending a wrong signal, that would cause the shifting problem. If you have a digital dash and have an RPM display, with the car in Neutral, watch the RMPs while slowly reving the engine. If it seems not correct then replace the sensor. Hope that helps
ash?

I just recently have been fighting the same problem with the same make/model/year vehicle. For myself, I would drive off and on through the day and it would run fine. Then suddenly after a start it would run rough and die. I would have to wait 20 to 60 mins before it would start again. I had it checked and fuel pump was only putting out around 19 psi. It should be around 41 psi. Had fuel pump replaced and no more problems. Furthermore, now it runs so much better. It's funny how over time I didn't notice how the performance was slowly degrading. Unfortunaley fuel pumps for this car run around $300.

If it is running rough or dies after you are running or you turn it off and try and start it and it acts as if it is flooding then sounds like you have a bad temperature sender. It is not showing the computer that the engine is warmed up and is telling the computer that it is still in cold state and is giving more fuel to try and start. Need to change your temperature sender.

SOUND LIKE RADIATOR HOSES AND RADIATOR.ONLY WAY TO CHECK IS FILL UP RADIATOR WITH COOLANT.CRANK UP CAR UNTIL WARMS UP.LET RADIATOR PRESSURE BUILD UP.THEN TURN OFF CAR.LOOK FOR WATER LEAKS AT RADIATOR HOSES AND AROUND THE RADIATOR.

when you say car lost power bought a new battery.sound like alternator not charging battery.with car running your voltage at battery should be 13.5 volts or 14.5 volts it not alternators need replacing.have garage replace alternator if faulty because 1993 to 1994 cars if you disconnect battery car would lose memory causing car not to idle.the car will stall out at a stop light or stop sign whole lot.it would relearn itself but the stalling out dangerous around a lot of traffic.

probably ignitor in distributor

The run rough problem is due a cyl.mis firing,it becaused buy a bad plug,plug wire,coil,or even the ing.module. the servive eng.light flashing is warning you that you have a cyl.misfire that can cause damaget to your catltic converter if you continue to drive it.with may lead to why you think you have a exhaust problem,it may be colgged.